存储过程结束了,messages中没有错误,但右下角说query completed with errors

javawhy 2009-09-25 03:33:27
When I execute a particular stored procedure in SQL Server 2005, the procedure completes and the results pane shows the number of records affected by the procedure. (The number of records affected indicate that the procedure completed successfully. Also, the correct number of records are inserted into a table.) However, the bottom of the query analyzer window says that the "query batch completed with errors." The result pane does not show any errors, only how many records were affected. Unfortunately, the procedure won't complete at all when it is called from a SQL Server job. The job reports failure, and the procedure does not insert all of the records into the table.

All the procedure does is select values into variables from various tables and then insert records into a table.

What might cause this? Is there a way to trap "soft" errors so I can see what is happening?

Your help is much appreciated.
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javawhy 2009-09-25
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不会设定maxerror number

根据大师的思想已经检查出部分脏数据,一会再看下情况
javawhy 2009-09-25
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[Quote=引用 7 楼 7761098 的回复:]
这种一般都是大批量数据处理时候的一些数据格式问题,设定maxerror number
然后分批处理,找出dirty data

[/Quote]


怎么设置啊,能否讲讲啊
7761098 2009-09-25
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这种一般都是大批量数据处理时候的一些数据格式问题,设定maxerror number
然后分批处理,找出dirty data
javawhy 2009-09-25
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网上一google发现,正好有个外国程序员也有这样错误,直接复制他的描述了.


我的情况是这样的.
我定义了一个游标,在下面的操作中修改了基表,第一次执行的时候是没有问题的,但再次执行的时候就出现 

代码跑完了,也出现影响的行.

但左下角出现 query complete with errors

MESSAGES中也没有错误提示

致命的是,接下来的存储过程语句就不执行了.

--小F-- 2009-09-25
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[Quote=引用 4 楼 dawugui 的回复:]
有请小P梁
[/Quote]

...
dawugui 2009-09-25
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有请小P梁
SqlServer2008 2009-09-25
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你是问问题还是考人啊
SqlServer2008 2009-09-25
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晕 问问题还用e文
soft_wsx 2009-09-25
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考验我!
xvii Contents Finishing Your Modules 154 Defining Module-Specific Errors 154 Choosing What to Export 155 Documenting Your Modules 156 Try It Out: Viewing Module Documentation 157 Testing Your Module 162 Running a Module as a Program 164 Try It Out: Running a Module 164 Creating a Whole Module 165 Try It Out: Finishing a Module 165 Try It Out: Smashing Imports 169 Installing Your Modules 170 Try It Out: Creating an Installable Package 171 Summary 174 Exercises 174 Chapter 11: Text Processing 175 Why Text Processing Is So Useful 175 Searching for Files 176 Clipping Logs 177 Sifting through Mail 178 Navigating the File System with the os Module 178 Try It Out: Listing Files and Playing with Paths 180 Try It Out: Searching for Files of a Particular Type 181 Try It Out: Refining a Search 183 Working with Regular Expressions and the re Module 184 Try It Out: Fun with Regular Expressions 186 Try It Out: Adding Tests 187 Summary 189 Exercises 189 Chapter 12: Testing 191 Assertions 191 Try It Out: Using Assert 192 Test Cases and Test Suites 193 Try It Out: Testing Addition 194 Try It Out: Testing Faulty Addition 195 Test Fixtures 196 Try It Out: Working with Test Fixtures 197 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xvii xviii Contents Putting It All Together with Extreme Programming 199 Implementing a Search Utility in Python 200 Try It Out: Writing a Test Suite First 201 Try It Out: A General-Purpose Search Framework 203 A More Powerful Python Search 205 Try It Out: Extending the Search Framework 206 Formal Testing in the Software Life Cycle 207 Summary 208 Chapter 13: Writing a GUI with Python 209 GUI Programming Toolkits for Python 209 PyGTK Introduction 210 pyGTK Resources 211 Creating GUI Widgets with pyGTK 213 Try It Out: Writing a Simple pyGTK Program 213 GUI Signals 214 GUI Helper Threads and the GUI Event Queue 216 Try It Out: Writing a Multithreaded pyGTK App 219 Widget Packing 222 Glade: a GUI Builder for pyGTK 223 GUI Builders for Other GUI Frameworks 224 Using libGlade with Python 225 A Glade Walkthrough 225 Starting Glade 226 Creating a Project 227 Using the Palette to Create a Window 227 Putting Widgets into the Window 228 Glade Creates an XML Representation of the GUI 230 Try It Out: Building a GUI from a Glade File 231 Creating a Real Glade Application 231 Advanced Widgets 238 Further Enhancing PyRAP 241 Summary 248 Exercises 248 Chapter 14: Accessing Databases 249 Working with DBM Persistent Dictionaries 250 Choosing a DBM Module 250 Creating Persistent Dictionaries 251 Try It Out: Creating a Persistent Dictionary 251 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xviii xix Contents Accessing Persistent Dictionaries 252 Try It Out: Accessing Persistent Dictionaries 253 Deciding When to Use DBM and When to Use a Relational Database 255 Working with Relational Databases 255 Writing SQL Statements 257 Defining Tables 259 Setting Up a Database 260 Try It Out: Creating a Gadfly Database 261 Using the Python Database APIs 262 Downloading Modules 263 Creating Connections 263 Working with Cursors 264 Try It Out: Inserting Records 264 Try It Out: Writing a Simple Query 266 Try It Out: Writing a Complex Join 267 Try It Out: Updating an Employee’s Manager 269 Try It Out: Removing Employees 270 Working with Transactions and Committing the Results 271 Examining Module Capabilities and Metadata 272 Handling Errors 272 Summary 273 Exercises 274 Chapter 15: Using Python for XML 275 What Is XML? 275 A Hierarchical Markup Language 275 A Family of Standards 277 What Is a Schema/DTD? 278 What Are Document Models For? 278 Do You Need One? 278 Document Type Definitions 278 An Example DTD 278 DTDs Aren’t Exactly XML 280 Limitations of DTDs 280 Schemas 280 An Example Schema 280 Schemas Are Pure XML 281 Schemas Are Hierarchical 281 Other Advantages of Schemas 281 Schemas Are Less Widely Supported 281 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xix xx Contents XPath 282 HTML as a Subset of XML 282 The HTML DTDs 283 HTMLParser 283 Try It Out: Using HTMLParser 283 htmllib 284 Try It Out: Using htmllib 284 XML Libraries Available for Python 285 Validating XML Using Python 285 What Is Validation? 286 Well-Formedness versus Validation 286 Available Tools 286 Try It Out: Validation Using xmlproc 286 What Is SAX? 287 Stream-based 288 Event-driven 288 What Is DOM? 288 In-memory Access 288 Why Use SAX or DOM 289 Capability Trade-Offs 289 Memory Considerations 289 Speed Considerations 289 SAX and DOM Parsers Available for Python 289 PyXML 290 xml.sax 290 xml.dom.minidom 290 Try It Out: Working with XML Using DOM 290 Try It Out: Working with XML Using SAX 292 Intro to XSLT 293 XSLT Is XML 293 Transformation and Formatting Language 293 Functional,Template-Driven 293 Using Python to Transform XML Using XSLT 294 Try It Out: Transforming XML with XSLT 294 Putting It All Together: Working with RSS 296 RSS Overview and Vocabulary 296 Making Sense of It All 296 RSS Vocabulary 297 An RSS DTD 297 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xx xxi Contents A Real-World Problem 297 Try It Out: Creating an RSS Feed 298 Creating the Document 300 Checking It Against the DTD 301 Another Real-World Problem 301 Try It Out: Creating An Aggregator 301 Summary 303 Exercises 303 Chapter 16: Network Programming 305 Try It Out: Sending Some E-mail 305 Understanding Protocols 307 Comparing Protocols and Programming Languages 307 The Internet Protocol Stack 308 A Little Bit About the Internet Protocol 309 Internet Addresses 309 Internet Ports 310 Sending Internet E-mail 311 The E-mail File Format 311 MIME Messages 313 MIME Encodings: Quoted-printable and Base64 313 MIME Content Types 314 Try It Out: Creating a MIME Message with an Attachment 315 MIME Multipart Messages 316 Try It Out: Building E-mail Messages with SmartMessage 320 Sending Mail with SMTP and smtplib 321 Try It Out: Sending Mail with MailServer 323 Retrieving Internet E-mail 323 Parsing a Local Mail Spool with mailbox 323 Try It Out: Printing a Summary of Your Mailbox 324 Fetching Mail from a POP3 Server with poplib 325 Try It Out: Printing a Summary of Your POP3 Mailbox 327 Fetching Mail from an IMAP Server with imaplib 327 Try It Out: Printing a Summary of Your IMAP Mailbox 329 IMAP’s Unique Message IDs 330 Try It Out: Fetching a Message by Unique ID 330 Secure POP3 and IMAP 331 Webmail Applications Are Not E-mail Applications 331 Socket Programming 331 Introduction to Sockets 332 Try It Out: Connecting to the SuperSimpleSocketServer with Telnet 333 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxi xxii Contents Binding to an External Hostname 334 The Mirror Server 335 Try It Out: Mirroring Text with the MirrorServer 336 The Mirror Client 336 SocketServer 337 Multithreaded Servers 339 The Python Chat Server 340 Design of the Python Chat Server 340 The Python Chat Server Protocol 341 Our Hypothetical Protocol in Action 341 Initial Connection 342 Chat Text 342 Server Commands 342 General Guidelines 343 The Python Chat Client 346 Single-Threaded Multitasking with select 348 Other Topics 350 Miscellaneous Considerations for Protocol Design 350 Trusted Servers 350 Terse Protocols 350 The Twisted Framework 351 Deferred Objects 351 The Peer-to-Peer Architecture 354 Summary 354 Exercises 354 Chapter 17: Extension Programming with C 355 Extension Module Outline 356 Building and Installing Extension Modules 358 Passing Parameters from Python to C 360 Returning Values from C to Python 363 The LAME Project 364 The LAME Extension Module 368 Using Python Objects from C Code 380 Summary 383 Exercises 383 Chapter 18: Writing Shareware and Commercial Programs 385 A Case Study: Background 385 How Much Python Should You Use? 386 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxii xxiii Contents Pure Python Licensing 387 Web Services Are Your Friend 388 Pricing Strategies 389 Watermarking 390 Other Models 394 Selling as a Platform,Rather Than a Product 395 Your Development Environment 395 Finding Python Programmers 396 Training non-Python Programmers 397 Python Employment Resources 397 Python Problems 397 Porting to Other Versions of Python 397 Porting to Other Operating Systems 398 Debugging Threads 399 Common Gotchas 399 Portable Distribution 400 Essential Libraries 401 Timeoutsocket 401 PyGTK 402 GEOip 402 Summary 403 Chapter 19: Numerical Programming 405 Numbers in Python 405 Integers 406 Long Integers 406 Floating-point Numbers 407 Formatting Numbers 408 Characters as Numbers 410 Mathematics 412 Arithmetic 412 Built-in Math Functions 414 The math Module 415 Complex Numbers 416 Arrays 418 The array Module 420 The numarray Package 422 Using Arrays 422 Computing the Standard Deviation 423 Summary 424 Exercises 425 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxiii xxiv Contents Chapter 20: Python in the Enterprise 427 Enterprise Applications 428 Document Management 428 The Evolution of Document Management Systems 429 What You Want in a Document Management System 430 People in Directories 431 Taking Action with Workflow 432 Auditing,Sarbanes-Oxley,and What You Need to Know 433 Auditing and Document Management 434 Working with Actual Enterprise Systems 435 Introducing the wftk Workflow Toolkit 435 Try It Out: Very Simple Record Retrieval 436 Try It Out: Very Simple Record Storage 438 Try It Out: Data Storage in MySQL 439 Try It Out: Storing and Retrieving Documents 441 Try It Out: A Document Retention Framework 446 The python-ldap Module 448 Try It Out: Using Basic OpenLDAP Tools 449 Try It Out: Simple LDAP Search 451 More LDAP 453 Back to the wftk 453 Try It Out: Simple Workflow Trigger 454 Try It Out: Action Queue Handler 456 Summary 458 Exercises 458 Chapter 21: Web Applications and Web Services 459 REST: The Architecture of the Web 460 Characteristics of REST 460 A Distributed Network of Interlinked Documents 461 A Client-Server Architecture 461 Servers Are Stateless 461 Resources 461 Representations 462 REST Operations 462 HTTP: Real-World REST 463 Try It Out: Python’s Three-Line Web Server 463 The Visible Web Server 464 Try It Out: Seeing an HTTP Request and Response 465 The HTTP Request 466 The HTTP Response 467 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxiv xxv Contents CGI: Turning Scripts into Web Applications 468 Try It Out: Running a CGI Script 469 The Web Server Makes a Deal with the CGI Script 470 CGI’s Special Environment Variables 471 Accepting User Input through HTML Forms 473 The cgi Module: Parsing HTML Forms 474 Try It Out: Printing Any HTML Form Submission 478 Building a Wiki 480 The BittyWiki Core Library 481 Back-end Storage 481 WikiWords 481 Writing the BittyWiki Core 481 Try It Out: Creating Wiki Pages from an Interactive Python Session 483 The BittyWiki Web Interface 484 Resources 484 Request Structure 484 But Wait—There’s More (Resources) 485 Wiki Markup 486 Web Services 493 How Web Services Work 494 REST Web Services 494 REST Quick Start: Finding Bargains on Amazon.com 495 Try It Out: Peeking at an Amazon Web Services Response 496 Introducing WishListBargainFinder 497 Giving BittyWiki a REST API 500 Wiki Search-and-Replace Using the REST Web Service 503 Try It Out: Wiki Searching and Replacing 507 XML-RPC 508 XML-RPC Quick Start: Get Tech News from Meerkat 509 The XML-RPC Request 511 Representation of Data in XML-RPC 512 The XML-RPC Response 513 If Something Goes Wrong 513 Exposing the BittyWiki API through XML-RPC 514 Try It Out: Manipulating BittyWiki through XML-RPC 517 Wiki Search-and-Replace Using the XML-RPC Web Service 518 SOAP 520 SOAP Quick Start: Surfing the Google API 520 The SOAP Request 522 The SOAP Response 524 If Something Goes Wrong 524 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxv xxvi Contents Exposing a SOAP Interface to BittyWiki 525 Try It Out: Manipulating BittyWiki through SOAP 526 Wiki Search-and-Replace Using the SOAP Web Service 527 Documenting Your Web Service API 529 Human-Readable API Documentation 529 The BittyWiki REST API Document 529 The BittyWiki XML-RPC API Document 529 The BittyWiki SOAP API Document 530 The XML-RPC Introspection API 530 Try It Out: Using the XML-RPC Introspection API 530 WSDL 531 Try It Out: Manipulating BittyWiki through a WSDL Proxy 533 Choosing a Web Service Standard 534 Web Service Etiquette 535 For Consumers of Web Services 535 For Producers of Web Services 535 Using Web Applications as Web Services 536 A Sampling of Publicly Available Web Services 536 Summary 538 Exercises 538 Chapter 22: Integrating Java with Python 539 Scripting within Java Applications 540 Comparing Python Implementations 541 Installing Jython 541 Running Jython 542 Running Jython Interactively 542 Try It Out: Running the Jython Interpreter 542 Running Jython Scripts 543 Try It Out Running a Python Script 543 Controlling the jython Script 544 Making Executable Commands 545 Try It Out: Making an Executable Script 546 Running Jython on Your Own 546 Packaging Jython-Based Applications 547 Integrating Java and Jython 547 Using Java Classes in Jython 548 Try It Out: Calling on Java Classes 548 Try It Out: Creating a User Interface from Jython 550 Accessing Databases from Jython 552 Working with the Python DB API 553 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xxvi xxvii Contents Setting Up a Database 554 Try It Out: Create Tables 555 Writing J2EE Servlets in Jython 558 Setting Up an Application Server 559 Adding the PyServlet to an Application Server 560 Extending HttpServlet 561 Try It Out: Writing a Python Servlet 562 Choosing Tools for Jython 564 Testing from Jython 565 Try It Out: Exploring Your Environment with Jython 565 Embedding the Jython Interpreter 566 Calling Jython Scripts from Java 566 Try It Out: Embedding Jython 567 Compiling Python Code to Java 568 Handling Differences between C Python and Jython 569 Summary 570 Exercises 571 Appendix A: Answers to Exercises 573 Appendix B: Online Resources 605 Appendix C: What’s New in Python 2.4 609 Glossary 613 Index 623 Contents Acknowledgments xxix Introduction xxxi Chapter 1: Programming Basics and Strings 1 How Programming Is Different from Using a Computer 1 Programming Is Consistency 2 Programming Is Control 2 Programming Copes with Change 2 What All That Means Together 3 The First Steps 3 Starting codeEditor 3 Using codeEditor’s Python Shell 4 Try It Out: Starting the Python Shell 4 Beginning to Use Python—Strings 5 What Is a String? 5 Why the Quotes? 6 Try It Out: Entering Strings with Different Quotes 6 Understanding Different Quotes 6 Putting Two Strings Together 8 Try It Out: Using + to Combine Strings 8 Putting Strings Together in Different Ways 9 Try It Out: Using a Format Specifier to Populate a String 9 Try It Out: More String Formatting 9 Displaying Strings with Print 10 Try It Out: Printing Text with Print 10 Summary 10 Exercises 11 Chapter 2: Numbers and Operators 13 Different Kinds of Numbers 13 Numbers in Python 14 Try It Out: Using Type with Different Numbers 14 Try It Out: Creating an Imaginary Number 15 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xi xii Contents Program Files 15 Try It Out: Using the Shell with the Editor 16 Using the Different Types 17 Try It Out Including Different Numbers in Strings 18 Try It Out: Escaping the % Sign in Strings 18 Basic Math 19 Try It Out Doing Basic Math 19 Try It Out: Using the Modulus Operation 20 Some Surprises 20 Try It Out: Printing the Results 21 Using Numbers 21 Order of Evaluation 21 Try It Out: Using Math Operations 21 Number Formats 22 Try It Out: Using Number Formats 22 Mistakes Will Happen 23 Try It Out: Making Mistakes 23 Some Unusual Cases 24 Try It Out: Formatting Numbers as Octal and Hexadecimal 24 Summary 24 Exercises 25 Chapter 3: Variables—Names for Values 27 Referring to Data – Using Names for Data 27 Try It Out: Assigning Values to Names 28 Changing Data Through Names 28 Try It Out: Altering Named Values 29 Copying Data 29 Names You Can’t Use and Some Rules 29 Using More Built-in Types 30 Tuples—Unchanging Sequences of Data 30 Try It Out: Creating and Using a Tuple 30 Try It Out: Accessing a Tuple Through Another Tuple 31 Lists—Changeable Sequences of Data 33 Try It Out Viewing the Elements of a List 33 Dictionaries—Groupings of Data Indexed by Name 34 Try It Out: Making a Dictionary 34 Try It Out: Getting the Keys from a Dictionary 35 Treating a String Like a List 36 Special Types 38 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xii xiii Contents Other Common Sequence Properties 38 Referencing the Last Elements 38 Ranges of Sequences 39 Try It Out: Slicing Sequences 39 Growing Lists by Appending Sequences 40 Using Lists to Temporarily Store Data 40 Try It Out: Popping Elements from a List 40 Summary 41 Exercises 42 Chapter 4: Making Decisions 43 Comparing Values—Are They the Same? 43 Try It Out: Comparing Values for Sameness 43 Doing the Opposite—Not Equal 45 Try It Out: Comparing Values for Difference 45 Comparing Values—Which One Is More? 45 Try It Out: Comparing Greater Than and Less Than 45 More Than or Equal,Less Than or Equal 47 Reversing True and False 47 Try It Out: Reversing the Outcome of a Test 47 Looking for the Results of More Than One Comparison 48 How to Get Decisions Made 48 Try It Out: Placing Tests within Tests 49 Repetition 51 How to Do Something—Again and Again 51 Try It Out: Using a while Loop 51 Stopping the Repetition 52 Try It Out: Using else While Repeating 54 Try It Out: Using continue to Keep Repeating 54 Handling Errors 55 Trying Things Out 55 Try It Out: Creating an Exception with Its Explanation 56 Summary 57 Exercises 58 Chapter 5: Functions 59 Putting Your Program into Its Own File 59 Try It Out: Run a Program with Python -i 61 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xiii xiv Contents Functions: Grouping Code under a Name 61 Try It Out: Defining a Function 61 Choosing a Name 62 Describing a Function in the Function 63 Try It Out: Displaying __doc__ 63 The Same Name in Two Different Places 64 Making Notes to Yourself 65 Try It Out: Experimenting with Comments 65 Asking a Function to Use a Value You Provide 66 Try It Out Invoking a Function with Parameters 67 Checking Your Parameters 68 Try It Out: Determining More Types with the type Function 69 Try It Out: Using Strings to Compare Types 69 Setting a Default Value for a Parameter—Just in Case 70 Try It Out: Setting a Default Parameter 70 Calling Functions from within Other Functions 71 Try It Out: Invoking the Completed Function 72 Functions Inside of Functions 72 Flagging an Error on Your Own Terms 73 Layers of Functions 74 How to Read Deeper Errors 74 Summary 75 Exercises 76 Chapter 6: Classes and Objects 79 Thinking About Programming 79 Objects You Already Know 79 Looking Ahead: How You Want to Use Objects 81 Defining a Class 81 How Code Can Be Made into an Object 81 Try It Out: Defining a Class 82 Try It Out: Creating an Object from Your Class 82 Try It Out: Writing an Internal Method 84 Try It Out: Writing Interface Methods 85 Try It Out: Using More Methods 87 Objects and Their Scope 89 Try It Out: Creating Another Class 89 Summary 92 Exercises 93 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xiv xv Contents Chapter 7: Organizing Programs 95 Modules 96 Importing a Module So That You Can Use It 96 Making a Module from Pre-existing Code 97 Try It Out: Creating a Module 97 Try It Out: Exploring Your New Module 98 Using Modules—Starting With the Command Line 99 Try It Out: Printing sys.argv 100 Changing How Import Works—Bringing in More 101 Packages 101 Try It Out: Making the Files in the Kitchen Class 102 Modules and Packages 103 Bringing Everything into the Current Scope 103 Try It Out: Exporting Modules from a Package 104 Re-importing Modules and Packages 104 Try It Out: Examining sys.modules 105 Basics of Testing Your Modules and Packages 106 Summary 106 Exercises 107 Chapter 8: Files and Directories 109 File Objects 109 Writing Text Files 110 Reading Text Files 111 Try It Out: Printing the Lengths of Lines in the Sample File 112 File Exceptions 113 Paths and Directories 113 Paths 114 Directory Contents 116 Try It Out: Getting the Contents of a Directory 116 Try It Out: Listing the Contents of Your Desktop or Home Directory 118 Obtaining Information about Files 118 Recursive Directory Listings 118 Renaming,Moving,Copying,and Removing Files 119 Example: Rotating Files 120 Creating and Removing Directories 121 Globbing 122 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xv xvi Contents Pickles 123 Try It Out: Creating a Pickle File 123 Pickling Tips 124 Efficient Pickling 125 Summary 125 Exercises 125 Chapter 9: Other Features of the Language 127 Lambda and Filter: Short Anonymous Functions 127 Reduce 128 Try It Out: Working with Reduce 128 Map: Short-Circuiting Loops 129 Try It Out: Use Map 129 Decisions within Lists—List Comprehension 130 Generating Lists for Loops 131 Try It Out: Examining an xrange Object 132 Special String Substitution Using Dictionaries 133 Try It Out: String Formatting with Dictionaries 133 Featured Modules 134 Getopt—Getting Options from the Command Line 134 Using More Than One Process 137 Threads—Doing Many Things in the Same Process 139 Storing Passwords 140 Summary 141 Exercises 142 Chapter 10: Building a Module 143 Exploring Modules 143 Importing Modules 145 Finding Modules 145 Digging through Modules 146 Creating Modules and Packages 150 Try It Out: Creating a Module with Functions 150 Working with Classes 151 Defining Object-Oriented Programming 151 Creating Classes 151 Try It Out: Creating a Meal Class 152 Extending Existing Classes 153 02_596543 ftoc.qxd 6/29/05 10:55 PM Page xvi
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We recommending using the ; development version only in development environments as errors shown to ; application users can inadvertently leak otherwise secure information. ; This is php.ini-development INI file. ;;;;;;;;;;;;;;;;;;; ; Quick Reference ; ;;;;;;;;;;;;;;;;;;; ; The following are all the settings which are different in either the production ; or development versions of the INIs with respect to PHP's default behavior. ; Please see the actual settings later in the document for more details as to why ; we recommend these changes in PHP's behavior. ; display_errors ; Default Value: On ; Development Value: On ; Production Value: Off ; display_startup_errors ; Default Value: Off ; Development Value: On ; Production Value: Off ; error_reporting ; Default Value: E_ALL & ~E_NOTICE & ~E_STRICT & ~E_DEPRECATED ; Development Value: E_ALL ; Production Value: E_ALL & ~E_DEPRECATED & ~E_STRICT ; html_errors ; Default Value: On ; Development Value: On ; Production value: On ; log_errors ; Default Value: Off ; Development Value: On ; Production Value: On ; max_input_time ; Default Value: -1 (Unlimited) ; Development Value: 60 (60 seconds) ; Production Value: 60 (60 seconds) ; output_buffering ; Default Value: Off ; Development Value: 4096 ; Production Value: 4096 ; register_argc_argv ; Default Value: On ; Development Value: Off ; Production Value: Off ; request_order ; Default Value: None ; Development Value: "GP" ; Production Value: "GP" ; session.gc_divisor ; Default Value: 100 ; Development Value: 1000 ; Production Value: 1000 ; session.hash_bits_per_character ; Default Value: 4 ; Development Value: 5 ; Production Value: 5 ; short_open_tag ; Default Value: On ; Development Value: Off ; Production Value: Off ; track_errors ; Default Value: Off ; Development Value: On ; Production Value: Off ; url_rewriter.tags ; Default Value: "a=href,area=href,frame=src,form=,fieldset=" ; Development Value: "a=href,area=href,frame=src,input=src,form=fakeentry" ; Production Value: "a=href,area=href,frame=src,input=src,form=fakeentry" ; variables_order ; Default Value: "EGPCS" ; Development Value: "GPCS" ; Production Value: "GPCS" ;;;;;;;;;;;;;;;;;;;; ; php.ini Options ; ;;;;;;;;;;;;;;;;;;;; ; Name for user-defined php.ini (.htaccess) files. 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It is ; generally recommended that should be used and that this feature ; should be disabled, as enabling it may result in issues when generating XML ; documents, however this remains supported for backward compatibility reasons. ; Note that this directive does not control the ed regardless of this directive. ; Default Value: On ; Development Value: Off ; Production Value: Off ; http://php.net/short-open-tag short_open_tag = Off ; Allow ASP-style <% %> tags. ; http://php.net/asp-tags asp_tags = Off ; The number of significant digits displayed in floating point numbers. ; http://php.net/precision precision = 14 ; Output buffering is a mechanism for controlling how much output data ; (excluding headers and cookies) PHP should keep internally before pushing that ; data to the client. If your application's output exceeds this setting, PHP ; will send that data in chunks of roughly the size you specify. ; Turning on this setting and managing its maximum buffer size can yield some ; interesting side-effects depending on your application and web server. ; You may be able to send headers and cookies after you've already sent output ; through print or echo. You also may see performance benefits if your server is ; emitting less packets due to buffered output versus PHP streaming the output ; as it gets it. On production servers, 4096 bytes is a good setting for performance ; reasons. ; Note: Output buffering can also be controlled via Output Buffering Control ; functions. ; Possible Values: ; On = Enabled and buffer is unlimited. (Use with caution) ; Off = Disabled ; Integer = Enables the buffer and sets its maximum size in bytes. ; Note: This directive is hardcoded to Off for the CLI SAPI ; Default Value: Off ; Development Value: 4096 ; Production Value: 4096 ; http://php.net/output-buffering output_buffering = 4096 ; You can redirect all of the output of your scripts to a function. For ; example, if you set output_handler to "mb_output_handler", character ; encoding will be transparently converted to the specified encoding. ; Setting any output handler automatically turns on output buffering. ; Note: People who wrote portable scripts should not depend on this ini ; directive. Instead, explicitly set the output handler using ob_start(). ; Using this ini directive may cause problems unless you know what script ; is doing. ; Note: You cannot use both "mb_output_handler" with "ob_iconv_handler" ; and you cannot use both "ob_gzhandler" and "zlib.output_compression". ; Note: output_handler must be empty if this is set 'On' !!!! ; Instead you must use zlib.output_handler. ; http://php.net/output-handler ;output_handler = ; Transparent output compression using the zlib library ; Valid values for this option are 'off', 'on', or a specific buffer size ; to be used for compression (default is 4KB) ; Note: Resulting chunk size may vary due to nature of compression. PHP ; outputs chunks that are few hundreds bytes each as a result of ; compression. If you prefer a larger chunk size for better ; performance, enable output_buffering in addition. ; Note: You need to use zlib.output_handler instead of the standard ; output_handler, or otherwise the output will be corrupted. ; http://php.net/zlib.output-compression zlib.output_compression = Off ; http://php.net/zlib.output-compression-level ;zlib.output_compression_level = -1 ; You cannot specify additional output handlers if zlib.output_compression ; is activated here. This setting does the same as output_handler but in ; a different order. ; http://php.net/zlib.output-handler ;zlib.output_handler = ; Implicit flush tells PHP to tell the output layer to flush itself ; automatically after every output block. This is equivalent to calling the ; PHP function flush() after each and every call to print() or echo() and each ; and every HTML block. Turning this option on has serious performance ; implications and is generally recommended for debugging purposes only. ; http://php.net/implicit-flush ; Note: This directive is hardcoded to On for the CLI SAPI implicit_flush = Off ; The unserialize callback function will be called (with the undefined class' ; name as parameter), if the unserializer finds an undefined class ; which should be instantiated. A warning appears if the specified function is ; not defined, or if the function doesn't include/implement the missing class. ; So only set this entry, if you really want to implement such a ; callback-function. unserialize_callback_func = ; When floats & doubles are serialized store serialize_precision significant ; digits after the floating point. The default value ensures that when floats ; are decoded with unserialize, the data will remain the same. serialize_precision = 17 ; open_basedir, if set, limits all file operations to the defined directory ; and below. This directive makes most sense if used in a per-directory ; or per-virtualhost web server configuration file. This directive is ; *NOT* affected by whether Safe Mode is turned On or Off. ; http://php.net/open-basedir ;open_basedir = ; This directive allows you to disable certain functions for security reasons. ; It receives a comma-delimited list of function names. This directive is ; *NOT* affected by whether Safe Mode is turned On or Off. ; http://php.net/disable-functions disable_functions = ; This directive allows you to disable certain classes for security reasons. ; It receives a comma-delimited list of class names. This directive is ; *NOT* affected by whether Safe Mode is turned On or Off. ; http://php.net/disable-classes disable_classes = ; Colors for Syntax Highlighting mode. Anything that's acceptable in ; would work. ; http://php.net/syntax-highlighting ;highlight.string = #DD0000 ;highlight.comment = #FF9900 ;highlight.keyword = #007700 ;highlight.default = #0000BB ;highlight.html = #000000 ; If enabled, the request will be allowed to complete even if the user aborts ; the request. Consider enabling it if executing long requests, which may end up ; being interrupted by the user or a browser timing out. PHP's default behavior ; is to disable this feature. ; http://php.net/ignore-user-abort ;ignore_user_abort = On ; Determines the size of the realpath cache to be used by PHP. This value should ; be increased on systems where PHP opens many files to reflect the quantity of ; the file operations performed. ; http://php.net/realpath-cache-size ;realpath_cache_size = 16k ; Duration of time, in seconds for which to cache realpath information for a given ; file or directory. For systems with rarely changing files, consider increasing this ; value. ; http://php.net/realpath-cache-ttl ;realpath_cache_ttl = 120 ; Enables or disables the circular reference collector. ; http://php.net/zend.enable-gc zend.enable_gc = On ; If enabled, scripts may be written in encodings that are incompatible with ; the scanner. CP936, Big5, CP949 and Shift_JIS are the examples of such ; encodings. To use this feature, mbstring extension must be enabled. ; Default: Off ;zend.multibyte = Off ; Allows to set the default encoding for the scripts. This value will be used ; unless "declare(encoding=...)" directive appears at the top of the script. ; Only affects if zend.multibyte is set. ; Default: "" ;zend.script_encoding = ;;;;;;;;;;;;;;;;; ; Miscellaneous ; ;;;;;;;;;;;;;;;;; ; Decides whether PHP may expose the fact that it is installed on the server ; (e.g. by adding its signature to the Web server header). It is no security ; threat in any way, but it makes it possible to determine whether you use PHP ; on your server or not. ; http://php.net/expose-php expose_php = On ;;;;;;;;;;;;;;;;;;; ; Resource Limits ; ;;;;;;;;;;;;;;;;;;; ; Maximum execution time of each script, in seconds ; http://php.net/max-execution-time ; Note: This directive is hardcoded to 0 for the CLI SAPI max_execution_time = 30 ; Maximum amount of time each script may spend parsing request data. It's a good ; idea to limit this time on productions servers in order to eliminate unexpectedly ; long running scripts. ; Note: This directive is hardcoded to -1 for the CLI SAPI ; Default Value: -1 (Unlimited) ; Development Value: 60 (60 seconds) ; Production Value: 60 (60 seconds) ; http://php.net/max-input-time max_input_time = 60 ; Maximum input variable nesting level ; http://php.net/max-input-nesting-level ;max_input_nesting_level = 64 ; How many GET/POST/COOKIE input variables may be accepted ; max_input_vars = 1000 ; Maximum amount of memory a script may consume (128MB) ; http://php.net/memory-limit memory_limit = 128M ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Error handling and logging ; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; This directive informs PHP of which errors, warnings and notices you would like ; it to take action for. The recommended way of setting values for this ; directive is through the use of the error level constants and bitwise ; operators. The error level constants are below here for convenience as well as ; some common settings and their meanings. ; By default, PHP is set to take action on all errors, notices and warnings EXCEPT ; those related to E_NOTICE and E_STRICT, which together cover best practices and ; recommended coding standards in PHP. For performance reasons, this is the ; recommend error reporting setting. Your production server shouldn't be wasting ; resources complaining about best practices and coding standards. That's what ; development servers and development settings are for. ; Note: The php.ini-development file has this setting as E_ALL. This ; means it pretty much reports everything which is exactly what you want during ; development and early testing. ; ; Error Level Constants: ; E_ALL - All errors and warnings (includes E_STRICT as of PHP 5.4.0) ; E_ERROR - fatal run-time errors ; E_RECOVERABLE_ERROR - almost fatal run-time errors ; E_WARNING - run-time warnings (non-fatal errors) ; E_PARSE - compile-time parse errors ; E_NOTICE - run-time notices (these are warnings which often result ; from a bug in your code, but it's possible that it was ; intentional (e.g., using an uninitialized variable and ; relying on the fact it's automatically initialized to an ; empty string) ; E_STRICT - run-time notices, enable to have PHP suggest changes ; to your code which will ensure the best interoperability ; and forward compatibility of your code ; E_CORE_ERROR - fatal errors that occur during PHP's initial startup ; E_CORE_WARNING - warnings (non-fatal errors) that occur during PHP's ; initial startup ; E_COMPILE_ERROR - fatal compile-time errors ; E_COMPILE_WARNING - compile-time warnings (non-fatal errors) ; E_USER_ERROR - user-generated error message ; E_USER_WARNING - user-generated warning message ; E_USER_NOTICE - user-generated notice message ; E_DEPRECATED - warn about code that will not work in future versions ; of PHP ; E_USER_DEPRECATED - user-generated deprecation warnings ; ; Common Values: ; E_ALL (Show all errors, warnings and notices including coding standards.) ; E_ALL & ~E_NOTICE (Show all errors, except for notices) ; E_ALL & ~E_NOTICE & ~E_STRICT (Show all errors, except for notices and coding standards warnings.) ; E_COMPILE_ERROR|E_RECOVERABLE_ERROR|E_ERROR|E_CORE_ERROR (Show only errors) ; Default Value: E_ALL & ~E_NOTICE & ~E_STRICT & ~E_DEPRECATED ; Development Value: E_ALL ; Production Value: E_ALL & ~E_DEPRECATED & ~E_STRICT ; http://php.net/error-reporting error_reporting = E_ALL ; This directive controls whether or not and where PHP will output errors, ; notices and warnings too. Error output is very useful during development, but ; it could be very dangerous in production environments. Depending on the code ; which is triggering the error, sensitive information could potentially leak ; out of your application such as database usernames and passwords or worse. ; It's recommended that errors be logged on production servers rather than ; having the errors sent to STDOUT. ; Possible Values: ; Off = Do not display any errors ; stderr = Display errors to STDERR (affects only CGI/CLI binaries!) ; On or stdout = Display errors to STDOUT ; Default Value: On ; Development Value: On ; Production Value: Off ; http://php.net/display-errors display_errors = On ; The display of errors which occur during PHP's startup sequence are handled ; separately from display_errors. PHP's default behavior is to suppress those ; errors from clients. Turning the display of startup errors on can be useful in ; debugging configuration problems. But, it's strongly recommended that you ; leave this setting off on production servers. ; Default Value: Off ; Development Value: On ; Production Value: Off ; http://php.net/display-startup-errors display_startup_errors = On ; Besides displaying errors, PHP can also log errors to locations such as a ; server-specific log, STDERR, or a location specified by the error_log ; directive found below. While errors should not be displayed on productions ; servers they should still be monitored and logging is a great way to do that. ; Default Value: Off ; Development Value: On ; Production Value: On ; http://php.net/log-errors log_errors = On ; Set maximum length of log_errors. In error_log information about the source is ; added. The default is 1024 and 0 allows to not apply any maximum length at all. ; http://php.net/log-errors-max-len log_errors_max_len = 1024 ; Do not log repeated messages. Repeated errors must occur in same file on same ; line unless ignore_repeated_source is set true. ; http://php.net/ignore-repeated-errors ignore_repeated_errors = Off ; Ignore source of message when ignoring repeated messages. When this setting ; is On you will not log errors with repeated messages from different files or ; source lines. ; http://php.net/ignore-repeated-source ignore_repeated_source = Off ; If this parameter is set to Off, then memory leaks will not be shown (on ; stdout or in the log). This has only effect in a debug compile, and if ; error reporting includes E_WARNING in the allowed list ; http://php.net/report-memleaks report_memleaks = On ; This setting is on by default. ;report_zend_debug = 0 ; Store the last error/warning message in $php_errormsg (boolean). Setting this value ; to On can assist in debugging and is appropriate for development servers. It should ; however be disabled on production servers. ; Default Value: Off ; Development Value: On ; Production Value: Off ; http://php.net/track-errors track_errors = On ; Turn off normal error reporting and emit XML-RPC error XML ; http://php.net/xmlrpc-errors ;xmlrpc_errors = 0 ; An XML-RPC faultCode ;xmlrpc_error_number = 0 ; When PHP displays or logs an error, it has the capability of formatting the ; error message as HTML for easier reading. This directive controls whether ; the error message is formatted as HTML or not. ; Note: This directive is hardcoded to Off for the CLI SAPI ; Default Value: On ; Development Value: On ; Production value: On ; http://php.net/html-errors html_errors = On ; If html_errors is set to On *and* docref_root is not empty, then PHP ; produces clickable error messages that direct to a page describing the error ; or function causing the error in detail. ; You can download a copy of the PHP manual from http://php.net/docs ; and change docref_root to the base URL of your local copy including the ; leading '/'. You must also specify the file extension being used including ; the dot. PHP's default behavior is to leave these settings empty, in which ; case no links to documentation are generated. ; Note: Never use this feature for production boxes. ; http://php.net/docref-root ; Examples ;docref_root = "/phpmanual/" ; http://php.net/docref-ext ;docref_ext = .html ; String to output before an error message. PHP's default behavior is to leave ; this setting blank. ; http://php.net/error-prepend-string ; Example: ;error_prepend_string = "" ; String to output after an error message. PHP's default behavior is to leave ; this setting blank. ; http://php.net/error-append-string ; Example: ;error_append_string = "" ; Log errors to specified file. PHP's default behavior is to leave this value ; empty. ; http://php.net/error-log ; Example: ;error_log = php_errors.log ; Log errors to syslog (Event Log on Windows). ;error_log = syslog ;windows.show_crt_warning ; Default value: 0 ; Development value: 0 ; Production value: 0 ;;;;;;;;;;;;;;;;; ; Data Handling ; ;;;;;;;;;;;;;;;;; ; The separator used in PHP generated URLs to separate arguments. ; PHP's default setting is "&". ; http://php.net/arg-separator.output ; Example: ;arg_separator.output = "&" ; List of separator(s) used by PHP to parse input URLs into variables. ; PHP's default setting is "&". ; NOTE: Every character in this directive is considered as separator! ; http://php.net/arg-separator.input ; Example: ;arg_separator.input = ";&" ; This directive determines which super global arrays are registered when PHP ; starts up. G,P,C,E & S are abbreviations for the following respective super ; globals: GET, POST, COOKIE, ENV and SERVER. There is a performance penalty ; paid for the registration of these arrays and because ENV is not as commonly ; used as the others, ENV is not recommended on productions servers. You ; can still get access to the environment variables through getenv() should you ; need to. ; Default Value: "EGPCS" ; Development Value: "GPCS" ; Production Value: "GPCS"; ; http://php.net/variables-order variables_order = "GPCS" ; This directive determines which super global data (G,P,C,E & S) should ; be registered into the super global array REQUEST. If so, it also determines ; the order in which that data is registered. The values for this directive are ; specified in the same manner as the variables_order directive, EXCEPT one. ; Leaving this value empty will cause PHP to use the value set in the ; variables_order directive. It does not mean it will leave the super globals ; array REQUEST empty. ; Default Value: None ; Development Value: "GP" ; Production Value: "GP" ; http://php.net/request-order request_order = "GP" ; This directive determines whether PHP registers $argv & $argc each time it ; runs. $argv contains an array of all the arguments passed to PHP when a script ; is invoked. $argc contains an integer representing the number of arguments ; that were passed when the script was invoked. These arrays are extremely ; useful when running scripts from the command line. When this directive is ; enabled, registering these variables consumes CPU cycles and memory each time ; a script is executed. For performance reasons, this feature should be disabled ; on production servers. ; Note: This directive is hardcoded to On for the CLI SAPI ; Default Value: On ; Development Value: Off ; Production Value: Off ; http://php.net/register-argc-argv register_argc_argv = Off ; When enabled, the ENV, REQUEST and SERVER variables are created when they're ; first used (Just In Time) instead of when the script starts. If these ; variables are not used within a script, having this directive on will result ; in a performance gain. The PHP directive register_argc_argv must be disabled ; for this directive to have any affect. ; http://php.net/auto-globals-jit auto_globals_jit = On ; Whether PHP will read the POST data. ; This option is enabled by default. ; Most likely, you won't want to disable this option globally. It causes $_POST ; and $_FILES to always be empty; the only way you will be able to read the ; POST data will be through the php://input stream wrapper. This can be useful ; to proxy requests or to process the POST data in a memory efficient fashion. ; http://php.net/enable-post-data-reading ;enable_post_data_reading = Off ; Maximum size of POST data that PHP will accept. ; Its value may be 0 to disable the limit. It is ignored if POST data reading ; is disabled through enable_post_data_reading. ; http://php.net/post-max-size post_max_size = 8M ; Automatically add files before PHP document. ; http://php.net/auto-prepend-file auto_prepend_file = ; Automatically add files after PHP document. ; http://php.net/auto-append-file auto_append_file = ; By default, PHP will output a character encoding using ; the Content-type: header. To disable sending of the charset, simply ; set it to be empty. ; ; PHP's built-in default is text/html ; http://php.net/default-mimetype default_mimetype = "text/html" ; PHP's default character set is set to empty. ; http://php.net/default-charset ;default_charset = "UTF-8" ; Always populate the $HTTP_RAW_POST_DATA variable. PHP's default behavior is ; to disable this feature. If post reading is disabled through ; enable_post_data_reading, $HTTP_RAW_POST_DATA is *NOT* populated. ; http://php.net/always-populate-raw-post-data ;always_populate_raw_post_data = On ;;;;;;;;;;;;;;;;;;;;;;;;; ; Paths and Directories ; ;;;;;;;;;;;;;;;;;;;;;;;;; ; UNIX: "/path1:/path2" ;include_path = ".:/php/includes" ; ; Windows: "\path1;\path2" ;include_path = ".;c:\php\includes" ; ; PHP's default setting for include_path is ".;/path/to/php/pear" ; http://php.net/include-path ; The root of the PHP pages, used only if nonempty. ; if PHP was not compiled with FORCE_REDIRECT, you SHOULD set doc_root ; if you are running php as a CGI under any web server (other than IIS) ; see documentation for security issues. The alternate is to use the ; cgi.force_redirect configuration below ; http://php.net/doc-root doc_root = ; The directory under which PHP opens the script using /~username used only ; if nonempty. ; http://php.net/user-dir user_dir = ; Directory in which the loadable extensions (modules) reside. ; http://php.net/extension-dir ; extension_dir = "./" ; On windows: ; extension_dir = "ext" ; Whether or not to enable the dl() function. The dl() function does NOT work ; properly in multithreaded servers, such as IIS or Zeus, and is automatically ; disabled on them. ; http://php.net/enable-dl enable_dl = Off ; cgi.force_redirect is necessary to provide security running PHP as a CGI under ; most web servers. Left undefined, PHP turns this on by default. You can ; turn it off here AT YOUR OWN RISK ; **You CAN safely turn this off for IIS, in fact, you MUST.** ; http://php.net/cgi.force-redirect ;cgi.force_redirect = 1 ; if cgi.nph is enabled it will force cgi to always sent Status: 200 with ; every request. PHP's default behavior is to disable this feature. ;cgi.nph = 1 ; if cgi.force_redirect is turned on, and you are not running under Apache or Netscape ; (iPlanet) web servers, you MAY need to set an environment variable name that PHP ; will look for to know it is OK to continue execution. Setting this variable MAY ; cause security issues, KNOW WHAT YOU ARE DOING FIRST. ; http://php.net/cgi.redirect-status-env ;cgi.redirect_status_env = ; cgi.fix_pathinfo provides *real* PATH_INFO/PATH_TRANSLATED support for CGI. PHP's ; previous behaviour was to set PATH_TRANSLATED to SCRIPT_FILENAME, and to not grok ; what PATH_INFO is. For more information on PATH_INFO, see the cgi specs. Setting ; this to 1 will cause PHP CGI to fix its paths to conform to the spec. A setting ; of zero causes PHP to behave as before. Default is 1. You should fix your scripts ; to use SCRIPT_FILENAME rather than PATH_TRANSLATED. ; http://php.net/cgi.fix-pathinfo ;cgi.fix_pathinfo=1 ; FastCGI under IIS (on WINNT based OS) supports the ability to impersonate ; security tokens of the calling client. This allows IIS to define the ; security context that the request runs under. mod_fastcgi under Apache ; does not currently support this feature (03/17/2002) ; Set to 1 if running under IIS. Default is zero. ; http://php.net/fastcgi.impersonate ;fastcgi.impersonate = 1 ; Disable logging through FastCGI connection. PHP's default behavior is to enable ; this feature. ;fastcgi.logging = 0 ; cgi.rfc2616_headers configuration option tells PHP what type of headers to ; use when sending HTTP response code. If it's set 0 PHP sends Status: header that ; is supported by Apache. When this option is set to 1 PHP will send ; RFC2616 compliant header. ; Default is zero. ; http://php.net/cgi.rfc2616-headers ;cgi.rfc2616_headers = 0 ;;;;;;;;;;;;;;;; ; File Uploads ; ;;;;;;;;;;;;;;;; ; Whether to allow HTTP file uploads. ; http://php.net/file-uploads file_uploads = On ; Temporary directory for HTTP uploaded files (will use system default if not ; specified). ; http://php.net/upload-tmp-dir ;upload_tmp_dir = ; Maximum allowed size for uploaded files. ; http://php.net/upload-max-filesize upload_max_filesize = 2M ; Maximum number of files that can be uploaded via a single request max_file_uploads = 20 ;;;;;;;;;;;;;;;;;; ; Fopen wrappers ; ;;;;;;;;;;;;;;;;;; ; Whether to allow the treatment of URLs (like http:// or ftp://) as files. ; http://php.net/allow-url-fopen allow_url_fopen = On ; Whether to allow include/require to open URLs (like http:// or ftp://) as files. ; http://php.net/allow-url-include allow_url_include = Off ; Define the anonymous ftp password (your email address). PHP's default setting ; for this is empty. ; http://php.net/from ;from="john@doe.com" ; Define the User-Agent string. PHP's default setting for this is empty. ; http://php.net/user-agent ;user_agent="PHP" ; Default timeout for socket based streams (seconds) ; http://php.net/default-socket-timeout default_socket_timeout = 60 ; If your scripts have to deal with files from Macintosh systems, ; or you are running on a Mac and need to deal with files from ; unix or win32 systems, setting this flag will cause PHP to ; automatically detect the EOL character in those files so that ; fgets() and file() will work regardless of the source of the file. ; http://php.net/auto-detect-line-endings ;auto_detect_line_endings = Off ;;;;;;;;;;;;;;;;;;;;;; ; Dynamic Extensions ; ;;;;;;;;;;;;;;;;;;;;;; ; If you wish to have an extension loaded automatically, use the following ; syntax: ; ; extension=modulename.extension ; ; For example, on Windows: ; ; extension=msql.dll ; ; ... or under UNIX: ; ; extension=msql.so ; ; ... or with a path: ; ; extension=/path/to/extension/msql.so ; ; If you only provide the name of the extension, PHP will look for it in its ; default extension directory. ; ; Windows Extensions ; Note that ODBC support is built in, so no dll is needed for it. ; Note that many DLL files are located in the extensions/ (PHP 4) ext/ (PHP 5) ; extension folders as well as the separate PECL DLL download (PHP 5). ; Be sure to appropriately set the extension_dir directive. ; ;extension=php_bz2.dll ;extension=php_curl.dll ;extension=php_fileinfo.dll ;extension=php_gd2.dll ;extension=php_gettext.dll ;extension=php_gmp.dll ;extension=php_intl.dll ;extension=php_imap.dll ;extension=php_interbase.dll ;extension=php_ldap.dll ;extension=php_mbstring.dll ;extension=php_exif.dll ; Must be after mbstring as it depends on it ;extension=php_mysql.dll ;extension=php_mysqli.dll ;extension=php_oci8.dll ; Use with Oracle 10gR2 Instant Client ;extension=php_oci8_11g.dll ; Use with Oracle 11gR2 Instant Client ;extension=php_openssl.dll ;extension=php_pdo_firebird.dll ;extension=php_pdo_mysql.dll ;extension=php_pdo_oci.dll ;extension=php_pdo_odbc.dll ;extension=php_pdo_pgsql.dll ;extension=php_pdo_sqlite.dll ;extension=php_pgsql.dll ;extension=php_pspell.dll ;extension=php_shmop.dll ; The MIBS data available in the PHP distribution must be installed. ; See http://www.php.net/manual/en/snmp.installation.php ;extension=php_snmp.dll ;extension=php_soap.dll ;extension=php_sockets.dll ;extension=php_sqlite3.dll ;extension=php_sybase_ct.dll ;extension=php_tidy.dll ;extension=php_xmlrpc.dll ;extension=php_xsl.dll ;;;;;;;;;;;;;;;;;;; ; Module Settings ; ;;;;;;;;;;;;;;;;;;; [CLI Server] ; Whether the CLI web server uses ANSI color coding in its terminal output. cli_server.color = On [Date] ; Defines the default timezone used by the date functions ; http://php.net/date.timezone ;date.timezone = ; http://php.net/date.default-latitude ;date.default_latitude = 31.7667 ; http://php.net/date.default-longitude ;date.default_longitude = 35.2333 ; http://php.net/date.sunrise-zenith ;date.sunrise_zenith = 90.583333 ; http://php.net/date.sunset-zenith ;date.sunset_zenith = 90.583333 [filter] ; http://php.net/filter.default ;filter.default = unsafe_raw ; http://php.net/filter.default-flags ;filter.default_flags = [iconv] ;iconv.input_encoding = ISO-8859-1 ;iconv.internal_encoding = ISO-8859-1 ;iconv.output_encoding = ISO-8859-1 [intl] ;intl.default_locale = ; This directive allows you to produce PHP errors when some error ; happens within intl functions. The value is the level of the error produced. ; Default is 0, which does not produce any errors. ;intl.error_level = E_WARNING [sqlite] ; http://php.net/sqlite.assoc-case ;sqlite.assoc_case = 0 [sqlite3] ;sqlite3.extension_dir = [Pcre] ;PCRE library backtracking limit. ; http://php.net/pcre.backtrack-limit ;pcre.backtrack_limit=100000 ;PCRE library recursion limit. ;Please note that if you set this value to a high number you may consume all ;the available process stack and eventually crash PHP (due to reaching the ;stack size limit imposed by the Operating System). ; http://php.net/pcre.recursion-limit ;pcre.recursion_limit=100000 [Pdo] ; Whether to pool ODBC connections. Can be one of "strict", "relaxed" or "off" ; http://php.net/pdo-odbc.connection-pooling ;pdo_odbc.connection_pooling=strict ;pdo_odbc.db2_instance_name [Pdo_mysql] ; If mysqlnd is used: Number of cache slots for the internal result set cache ; http://php.net/pdo_mysql.cache_size pdo_mysql.cache_size = 2000 ; Default socket name for local MySQL connects. If empty, uses the built-in ; MySQL defaults. ; http://php.net/pdo_mysql.default-socket pdo_mysql.default_socket= [Phar] ; http://php.net/phar.readonly ;phar.readonly = On ; http://php.net/phar.require-hash ;phar.require_hash = On ;phar.cache_list = [mail function] ; For Win32 only. ; http://php.net/smtp SMTP = localhost ; http://php.net/smtp-port smtp_port = 25 ; For Win32 only. ; http://php.net/sendmail-from ;sendmail_from = me@example.com ; For Unix only. You may supply arguments as well (default: "sendmail -t -i"). ; http://php.net/sendmail-path ;sendmail_path = ; Force the addition of the specified parameters to be passed as extra parameters ; to the sendmail binary. These parameters will always replace the value of ; the 5th parameter to mail(), even in safe mode. ;mail.force_extra_parameters = ; Add X-PHP-Originating-Script: that will include uid of the script followed by the filename mail.add_x_header = On ; The path to a log file that will log all mail() calls. Log entries include ; the full path of the script, line number, To address and headers. ;mail.log = ; Log mail to syslog (Event Log on Windows). ;mail.log = syslog [SQL] ; http://php.net/sql.safe-mode sql.safe_mode = Off [ODBC] ; http://php.net/odbc.default-db ;odbc.default_db = Not yet implemented ; http://php.net/odbc.default-user ;odbc.default_user = Not yet implemented ; http://php.net/odbc.default-pw ;odbc.default_pw = Not yet implemented ; Controls the ODBC cursor model. ; Default: SQL_CURSOR_STATIC (default). ;odbc.default_cursortype ; Allow or prevent persistent links. ; http://php.net/odbc.allow-persistent odbc.allow_persistent = On ; Check that a connection is still valid before reuse. ; http://php.net/odbc.check-persistent odbc.check_persistent = On ; Maximum number of persistent links. -1 means no limit. ; http://php.net/odbc.max-persistent odbc.max_persistent = -1 ; Maximum number of links (persistent + non-persistent). -1 means no limit. ; http://php.net/odbc.max-links odbc.max_links = -1 ; Handling of LONG fields. Returns number of bytes to variables. 0 means ; passthru. ; http://php.net/odbc.defaultlrl odbc.defaultlrl = 4096 ; Handling of binary data. 0 means passthru, 1 return as is, 2 convert to char. ; See the documentation on odbc_binmode and odbc_longreadlen for an explanation ; of odbc.defaultlrl and odbc.defaultbinmode ; http://php.net/odbc.defaultbinmode odbc.defaultbinmode = 1 ;birdstep.max_links = -1 [Interbase] ; Allow or prevent persistent links. ibase.allow_persistent = 1 ; Maximum number of persistent links. -1 means no limit. ibase.max_persistent = -1 ; Maximum number of links (persistent + non-persistent). -1 means no limit. ibase.max_links = -1 ; Default database name for ibase_connect(). ;ibase.default_db = ; Default username for ibase_connect(). ;ibase.default_user = ; Default password for ibase_connect(). ;ibase.default_password = ; Default charset for ibase_connect(). ;ibase.default_charset = ; Default timestamp format. ibase.timestampformat = "%Y-%m-%d %H:%M:%S" ; Default date format. ibase.dateformat = "%Y-%m-%d" ; Default time format. ibase.timeformat = "%H:%M:%S" [MySQL] ; Allow accessing, from PHP's perspective, local files with LOAD DATA statements ; http://php.net/mysql.allow_local_infile mysql.allow_local_infile = On ; Allow or prevent persistent links. ; http://php.net/mysql.allow-persistent mysql.allow_persistent = On ; If mysqlnd is used: Number of cache slots for the internal result set cache ; http://php.net/mysql.cache_size mysql.cache_size = 2000 ; Maximum number of persistent links. -1 means no limit. ; http://php.net/mysql.max-persistent mysql.max_persistent = -1 ; Maximum number of links (persistent + non-persistent). -1 means no limit. ; http://php.net/mysql.max-links mysql.max_links = -1 ; Default port number for mysql_connect(). If unset, mysql_connect() will use ; the $MYSQL_TCP_PORT or the mysql-tcp entry in /etc/services or the ; compile-time value defined MYSQL_PORT (in that order). Win32 will only look ; at MYSQL_PORT. ; http://php.net/mysql.default-port mysql.default_port = ; Default socket name for local MySQL connects. If empty, uses the built-in ; MySQL defaults. ; http://php.net/mysql.default-socket mysql.default_socket = ; Default host for mysql_connect() (doesn't apply in safe mode). ; http://php.net/mysql.default-host mysql.default_host = ; Default user for mysql_connect() (doesn't apply in safe mode). ; http://php.net/mysql.default-user mysql.default_user = ; Default password for mysql_connect() (doesn't apply in safe mode). ; Note that this is generally a *bad* idea to store passwords in this file. ; *Any* user with PHP access can run 'echo get_cfg_var("mysql.default_password") ; and reveal this password! And of course, any users with read access to this ; file will be able to reveal the password as well. ; http://php.net/mysql.default-password mysql.default_password = ; Maximum time (in seconds) for connect timeout. -1 means no limit ; http://php.net/mysql.connect-timeout mysql.connect_timeout = 60 ; Trace mode. When trace_mode is active (=On), warnings for table/index scans and ; SQL-Errors will be displayed. ; http://php.net/mysql.trace-mode mysql.trace_mode = Off [MySQLi] ; Maximum number of persistent links. -1 means no limit. ; http://php.net/mysqli.max-persistent mysqli.max_persistent = -1 ; Allow accessing, from PHP's perspective, local files with LOAD DATA statements ; http://php.net/mysqli.allow_local_infile ;mysqli.allow_local_infile = On ; Allow or prevent persistent links. ; http://php.net/mysqli.allow-persistent mysqli.allow_persistent = On ; Maximum number of links. -1 means no limit. ; http://php.net/mysqli.max-links mysqli.max_links = -1 ; If mysqlnd is used: Number of cache slots for the internal result set cache ; http://php.net/mysqli.cache_size mysqli.cache_size = 2000 ; Default port number for mysqli_connect(). If unset, mysqli_connect() will use ; the $MYSQL_TCP_PORT or the mysql-tcp entry in /etc/services or the ; compile-time value defined MYSQL_PORT (in that order). Win32 will only look ; at MYSQL_PORT. ; http://php.net/mysqli.default-port mysqli.default_port = 3306 ; Default socket name for local MySQL connects. If empty, uses the built-in ; MySQL defaults. ; http://php.net/mysqli.default-socket mysqli.default_socket = ; Default host for mysql_connect() (doesn't apply in safe mode). ; http://php.net/mysqli.default-host mysqli.default_host = ; Default user for mysql_connect() (doesn't apply in safe mode). ; http://php.net/mysqli.default-user mysqli.default_user = ; Default password for mysqli_connect() (doesn't apply in safe mode). ; Note that this is generally a *bad* idea to store passwords in this file. ; *Any* user with PHP access can run 'echo get_cfg_var("mysqli.default_pw") ; and reveal this password! And of course, any users with read access to this ; file will be able to reveal the password as well. ; http://php.net/mysqli.default-pw mysqli.default_pw = ; Allow or prevent reconnect mysqli.reconnect = Off [mysqlnd] ; Enable / Disable collection of general statistics by mysqlnd which can be ; used to tune and monitor MySQL operations. ; http://php.net/mysqlnd.collect_statistics mysqlnd.collect_statistics = On ; Enable / Disable collection of memory usage statistics by mysqlnd which can be ; used to tune and monitor MySQL operations. ; http://php.net/mysqlnd.collect_memory_statistics mysqlnd.collect_memory_statistics = On ; Size of a pre-allocated buffer used when sending commands to MySQL in bytes. ; http://php.net/mysqlnd.net_cmd_buffer_size ;mysqlnd.net_cmd_buffer_size = 2048 ; Size of a pre-allocated buffer used for reading data sent by the server in ; bytes. ; http://php.net/mysqlnd.net_read_buffer_size ;mysqlnd.net_read_buffer_size = 32768 [OCI8] ; Connection: Enables privileged connections using external ; credentials (OCI_SYSOPER, OCI_SYSDBA) ; http://php.net/oci8.privileged-connect ;oci8.privileged_connect = Off ; Connection: The maximum number of persistent OCI8 connections per ; process. Using -1 means no limit. ; http://php.net/oci8.max-persistent ;oci8.max_persistent = -1 ; Connection: The maximum number of seconds a process is allowed to ; maintain an idle persistent connection. Using -1 means idle ; persistent connections will be maintained forever. ; http://php.net/oci8.persistent-timeout ;oci8.persistent_timeout = -1 ; Connection: The number of seconds that must pass before issuing a ; ping during oci_pconnect() to check the connection validity. When ; set to 0, each oci_pconnect() will cause a ping. Using -1 disables ; pings completely. ; http://php.net/oci8.ping-interval ;oci8.ping_interval = 60 ; Connection: Set this to a user chosen connection class to be used ; for all pooled server requests with Oracle 11g Database Resident ; Connection Pooling (DRCP). To use DRCP, this value should be set to ; the same string for all web servers running the same application, ; the database pool must be configured, and the connection string must ; specify to use a pooled server. ;oci8.connection_class = ; High Availability: Using On lets PHP receive Fast Application ; Notification (FAN) events generated when a database node fails. The ; database must also be configured to post FAN events. ;oci8.events = Off ; Tuning: This option enables statement caching, and specifies how ; many statements to cache. Using 0 disables statement caching. ; http://php.net/oci8.statement-cache-size ;oci8.statement_cache_size = 20 ; Tuning: Enables statement prefetching and sets the default number of ; rows that will be fetched automatically after statement execution. ; http://php.net/oci8.default-prefetch ;oci8.default_prefetch = 100 ; Compatibility. Using On means oci_close() will not close ; oci_connect() and oci_new_connect() connections. ; http://php.net/oci8.old-oci-close-semantics ;oci8.old_oci_close_semantics = Off [PostgreSQL] ; Allow or prevent persistent links. ; http://php.net/pgsql.allow-persistent pgsql.allow_persistent = On ; Detect broken persistent links always with pg_pconnect(). ; Auto reset feature requires a little overheads. ; http://php.net/pgsql.auto-reset-persistent pgsql.auto_reset_persistent = Off ; Maximum number of persistent links. -1 means no limit. ; http://php.net/pgsql.max-persistent pgsql.max_persistent = -1 ; Maximum number of links (persistent+non persistent). -1 means no limit. ; http://php.net/pgsql.max-links pgsql.max_links = -1 ; Ignore PostgreSQL backends Notice message or not. ; Notice message logging require a little overheads. ; http://php.net/pgsql.ignore-notice pgsql.ignore_notice = 0 ; Log PostgreSQL backends Notice message or not. ; Unless pgsql.ignore_notice=0, module cannot log notice message. ; http://php.net/pgsql.log-notice pgsql.log_notice = 0 [Sybase-CT] ; Allow or prevent persistent links. ; http://php.net/sybct.allow-persistent sybct.allow_persistent = On ; Maximum number of persistent links. -1 means no limit. ; http://php.net/sybct.max-persistent sybct.max_persistent = -1 ; Maximum number of links (persistent + non-persistent). -1 means no limit. ; http://php.net/sybct.max-links sybct.max_links = -1 ; Minimum server message severity to display. ; http://php.net/sybct.min-server-severity sybct.min_server_severity = 10 ; Minimum client message severity to display. ; http://php.net/sybct.min-client-severity sybct.min_client_severity = 10 ; Set per-context timeout ; http://php.net/sybct.timeout ;sybct.timeout= ;sybct.packet_size ; The maximum time in seconds to wait for a connection attempt to succeed before returning failure. ; Default: one minute ;sybct.login_timeout= ; The name of the host you claim to be connecting from, for display by sp_who. ; Default: none ;sybct.hostname= ; Allows you to define how often deadlocks are to be retried. -1 means "forever". ; Default: 0 ;sybct.deadlock_retry_count= [bcmath] ; Number of decimal digits for all bcmath functions. ; http://php.net/bcmath.scale bcmath.scale = 0 [browscap] ; http://php.net/browscap ;browscap = extra/browscap.ini [Session] ; Handler used to store/retrieve data. ; http://php.net/session.save-handler session.save_handler = files ; Argument passed to save_handler. In the case of files, this is the path ; where data files are stored. Note: Windows users have to change this ; variable in order to use PHP's session functions. ; ; The path can be defined as: ; ; session.save_path = "N;/path" ; ; where N is an integer. Instead of storing all the session files in ; /path, what this will do is use subdirectories N-levels deep, and ; store the session data in those directories. This is useful if you ; or your OS have problems with lots of files in one directory, and is ; a more efficient layout for servers that handle lots of sessions. ; ; NOTE 1: PHP will not create this directory structure automatically. ; You can use the script in the ext/session dir for that purpose. ; NOTE 2: See the section on garbage collection below if you choose to ; use subdirectories for session storage ; ; The file storage module creates files using mode 600 by default. ; You can change that by using ; ; session.save_path = "N;MODE;/path" ; ; where MODE is the octal representation of the mode. Note that this ; does not overwrite the process's umask. ; http://php.net/session.save-path ;session.save_path = "/tmp" ; Whether to use cookies. ; http://php.net/session.use-cookies session.use_cookies = 1 ; http://php.net/session.cookie-secure ;session.cookie_secure = ; This option forces PHP to fetch and use a cookie for storing and maintaining ; the session id. We encourage this operation as it's very helpful in combating ; session hijacking when not specifying and managing your own session id. It is ; not the end all be all of session hijacking defense, but it's a good start. ; http://php.net/session.use-only-cookies session.use_only_cookies = 1 ; Name of the session (used as cookie name). ; http://php.net/session.name session.name = PHPSESSID ; Initialize session on request startup. ; http://php.net/session.auto-start session.auto_start = 0 ; Lifetime in seconds of cookie or, if 0, until browser is restarted. ; http://php.net/session.cookie-lifetime session.cookie_lifetime = 0 ; The path for which the cookie is valid. ; http://php.net/session.cookie-path session.cookie_path = / ; The domain for which the cookie is valid. ; http://php.net/session.cookie-domain session.cookie_domain = ; Whether or not to add the httpOnly flag to the cookie, which makes it inaccessible to browser scripting languages such as JavaScript. ; http://php.net/session.cookie-httponly session.cookie_httponly = ; Handler used to serialize data. php is the standard serializer of PHP. ; http://php.net/session.serialize-handler session.serialize_handler = php ; Defines the probability that the 'garbage collection' process is started ; on every session initialization. The probability is calculated by using ; gc_probability/gc_divisor. Where session.gc_probability is the numerator ; and gc_divisor is the denominator in the equation. Setting this value to 1 ; when the session.gc_divisor value is 100 will give you approximately a 1% chance ; the gc will run on any give request. ; Default Value: 1 ; Development Value: 1 ; Production Value: 1 ; http://php.net/session.gc-probability session.gc_probability = 1 ; Defines the probability that the 'garbage collection' process is started on every ; session initialization. The probability is calculated by using the following equation: ; gc_probability/gc_divisor. Where session.gc_probability is the numerator and ; session.gc_divisor is the denominator in the equation. Setting this value to 1 ; when the session.gc_divisor value is 100 will give you approximately a 1% chance ; the gc will run on any give request. Increasing this value to 1000 will give you ; a 0.1% chance the gc will run on any give request. For high volume production servers, ; this is a more efficient approach. ; Default Value: 100 ; Development Value: 1000 ; Production Value: 1000 ; http://php.net/session.gc-divisor session.gc_divisor = 1000 ; After this number of seconds, stored data will be seen as 'garbage' and ; cleaned up by the garbage collection process. ; http://php.net/session.gc-maxlifetime session.gc_maxlifetime = 1440 ; NOTE: If you are using the subdirectory option for storing session files ; (see session.save_path above), then garbage collection does *not* ; happen automatically. You will need to do your own garbage ; collection through a shell script, cron entry, or some other method. ; For example, the following script would is the equivalent of ; setting session.gc_maxlifetime to 1440 (1440 seconds = 24 minutes): ; find /path/to/sessions -cmin +24 -type f | xargs rm ; Check HTTP Referer to invalidate externally stored URLs containing ids. ; HTTP_REFERER has to contain this substring for the session to be ; considered as valid. ; http://php.net/session.referer-check session.referer_check = ; How many bytes to read from the file. ; http://php.net/session.entropy-length ;session.entropy_length = 32 ; Specified here to create the session id. ; http://php.net/session.entropy-file ; Defaults to /dev/urandom ; On systems that don't have /dev/urandom but do have /dev/arandom, this will default to /dev/arandom ; If neither are found at compile time, the default is no entropy file. ; On windows, setting the entropy_length setting will activate the ; Windows random source (using the CryptoAPI) ;session.entropy_file = /dev/urandom ; Set to {nocache,private,public,} to determine HTTP caching aspects ; or leave this empty to avoid sending anti-caching headers. ; http://php.net/session.cache-limiter session.cache_limiter = nocache ; Document expires after n minutes. ; http://php.net/session.cache-expire session.cache_expire = 180 ; trans sid support is disabled by default. ; Use of trans sid may risk your users security. ; Use this option with caution. ; - User may send URL contains active session ID ; to other person via. email/irc/etc. ; - URL that contains active session ID may be stored ; in publicly accessible computer. ; - User may access your site with the same session ID ; always using URL stored in browser's history or bookmarks. ; http://php.net/session.use-trans-sid session.use_trans_sid = 0 ; Select a hash function for use in generating session ids. ; Possible Values ; 0 (MD5 128 bits) ; 1 (SHA-1 160 bits) ; This option may also be set to the name of any hash function supported by ; the hash extension. A list of available hashes is returned by the hash_algos() ; function. ; http://php.net/session.hash-function session.hash_function = 0 ; Define how many bits are stored in each character when converting ; the binary hash data to something readable. ; Possible values: ; 4 (4 bits: 0-9, a-f) ; 5 (5 bits: 0-9, a-v) ; 6 (6 bits: 0-9, a-z, A-Z, "-", ",") ; Default Value: 4 ; Development Value: 5 ; Production Value: 5 ; http://php.net/session.hash-bits-per-character session.hash_bits_per_character = 5 ; The URL rewriter will look for URLs in a defined set of HTML tags. ; form/fieldset are special; if you include them here, the rewriter will ; add a hidden field with the info which is otherwise appended ; to URLs. If you want XHTML conformity, remove the form entry. ; Note that all valid entries require a "=", even if no value follows. ; Default Value: "a=href,area=href,frame=src,form=,fieldset=" ; Development Value: "a=href,area=href,frame=src,input=src,form=fakeentry" ; Production Value: "a=href,area=href,frame=src,input=src,form=fakeentry" ; http://php.net/url-rewriter.tags url_rewriter.tags = "a=href,area=href,frame=src,input=src,form=fakeentry" ; Enable upload progress tracking in $_SESSION ; Default Value: On ; Development Value: On ; Production Value: On ; http://php.net/session.upload-progress.enabled ;session.upload_progress.enabled = On ; Cleanup the progress information as soon as all POST data has been read ; (i.e. upload completed). ; Default Value: On ; Development Value: On ; Production Value: On ; http://php.net/session.upload-progress.cleanup ;session.upload_progress.cleanup = On ; A prefix used for the upload progress key in $_SESSION ; Default Value: "upload_progress_" ; Development Value: "upload_progress_" ; Production Value: "upload_progress_" ; http://php.net/session.upload-progress.prefix ;session.upload_progress.prefix = "upload_progress_" ; The index name (concatenated with the prefix) in $_SESSION ; containing the upload progress information ; Default Value: "PHP_SESSION_UPLOAD_PROGRESS" ; Development Value: "PHP_SESSION_UPLOAD_PROGRESS" ; Production Value: "PHP_SESSION_UPLOAD_PROGRESS" ; http://php.net/session.upload-progress.name ;session.upload_progress.name = "PHP_SESSION_UPLOAD_PROGRESS" ; How frequently the upload progress should be updated. ; Given either in percentages (per-file), or in bytes ; Default Value: "1%" ; Development Value: "1%" ; Production Value: "1%" ; http://php.net/session.upload-progress.freq ;session.upload_progress.freq = "1%" ; The minimum delay between updates, in seconds ; Default Value: 1 ; Development Value: 1 ; Production Value: 1 ; http://php.net/session.upload-progress.min-freq ;session.upload_progress.min_freq = "1" [MSSQL] ; Allow or prevent persistent links. mssql.allow_persistent = On ; Maximum number of persistent links. -1 means no limit. mssql.max_persistent = -1 ; Maximum number of links (persistent+non persistent). -1 means no limit. mssql.max_links = -1 ; Minimum error severity to display. mssql.min_error_severity = 10 ; Minimum message severity to display. mssql.min_message_severity = 10 ; Compatibility mode with old versions of PHP 3.0. mssql.compatability_mode = Off ; Connect timeout ;mssql.connect_timeout = 5 ; Query timeout ;mssql.timeout = 60 ; Valid range 0 - 2147483647. Default = 4096. ;mssql.textlimit = 4096 ; Valid range 0 - 2147483647. Default = 4096. ;mssql.textsize = 4096 ; Limits the number of records in each batch. 0 = all records in one batch. ;mssql.batchsize = 0 ; Specify how datetime and datetim4 columns are returned ; On => Returns data converted to SQL server settings ; Off => Returns values as YYYY-MM-DD hh:mm:ss ;mssql.datetimeconvert = On ; Use NT authentication when connecting to the server mssql.secure_connection = Off ; Specify max number of processes. -1 = library default ; msdlib defaults to 25 ; FreeTDS defaults to 4096 ;mssql.max_procs = -1 ; Specify client character set. ; If empty or not set the client charset from freetds.conf is used ; This is only used when compiled with FreeTDS ;mssql.charset = "ISO-8859-1" [Assertion] ; Assert(expr); active by default. ; http://php.net/assert.active ;assert.active = On ; Issue a PHP warning for each failed assertion. ; http://php.net/assert.warning ;assert.warning = On ; Don't bail out by default. ; http://php.net/assert.bail ;assert.bail = Off ; User-function to be called if an assertion fails. ; http://php.net/assert.callback ;assert.callback = 0 ; Eval the expression with current error_reporting(). Set to true if you want ; error_reporting(0) around the eval(). ; http://php.net/assert.quiet-eval ;assert.quiet_eval = 0 [COM] ; path to a file containing GUIDs, IIDs or filenames of files with TypeLibs ; http://php.net/com.typelib-file ;com.typelib_file = ; allow Distributed-COM calls ; http://php.net/com.allow-dcom ;com.allow_dcom = true ; autoregister constants of a components typlib on com_load() ; http://php.net/com.autoregister-typelib ;com.autoregister_typelib = true ; register constants casesensitive ; http://php.net/com.autoregister-casesensitive ;com.autoregister_casesensitive = false ; show warnings on duplicate constant registrations ; http://php.net/com.autoregister-verbose ;com.autoregister_verbose = true ; The default character set code-page to use when passing strings to and from COM objects. ; Default: system ANSI code page ;com.code_page= [mbstring] ; language for internal character representation. ; http://php.net/mbstring.language ;mbstring.language = Japanese ; internal/script encoding. ; Some encoding cannot work as internal encoding. ; (e.g. SJIS, BIG5, ISO-2022-*) ; http://php.net/mbstring.internal-encoding ;mbstring.internal_encoding = EUC-JP ; http input encoding. ; http://php.net/mbstring.http-input ;mbstring.http_input = auto ; http output encoding. mb_output_handler must be ; registered as output buffer to function ; http://php.net/mbstring.http-output ;mbstring.http_output = SJIS ; enable automatic encoding translation according to ; mbstring.internal_encoding setting. Input chars are ; converted to internal encoding by setting this to On. ; Note: Do _not_ use automatic encoding translation for ; portable libs/applications. ; http://php.net/mbstring.encoding-translation ;mbstring.encoding_translation = Off ; automatic encoding detection order. ; auto means ; http://php.net/mbstring.detect-order ;mbstring.detect_order = auto ; substitute_character used when character cannot be converted ; one from another ; http://php.net/mbstring.substitute-character ;mbstring.substitute_character = none; ; overload(replace) single byte functions by mbstring functions. ; mail(), ereg(), etc are overloaded by mb_send_mail(), mb_ereg(), ; etc. Possible values are 0,1,2,4 or combination of them. ; For example, 7 for overload everything. ; 0: No overload ; 1: Overload mail() function ; 2: Overload str*() functions ; 4: Overload ereg*() functions ; http://php.net/mbstring.func-overload ;mbstring.func_overload = 0 ; enable strict encoding detection. ;mbstring.strict_detection = Off ; This directive specifies the regex pattern of content types for which mb_output_handler() ; is activated. ; Default: mbstring.http_output_conv_mimetype=^(text/|application/xhtml\+xml) ;mbstring.http_output_conv_mimetype= [gd] ; Tell the jpeg decode to ignore warnings and try to create ; a gd image. The warning will then be displayed as notices ; disabled by default ; http://php.net/gd.jpeg-ignore-warning ;gd.jpeg_ignore_warning = 0 [exif] ; Exif UNICODE user comments are handled as UCS-2BE/UCS-2LE and JIS as JIS. ; With mbstring support this will automatically be converted into the encoding ; given by corresponding encode setting. When empty mbstring.internal_encoding ; is used. For the decode settings you can distinguish between motorola and ; intel byte order. A decode setting cannot be empty. ; http://php.net/exif.encode-unicode ;exif.encode_unicode = ISO-8859-15 ; http://php.net/exif.decode-unicode-motorola ;exif.decode_unicode_motorola = UCS-2BE ; http://php.net/exif.decode-unicode-intel ;exif.decode_unicode_intel = UCS-2LE ; http://php.net/exif.encode-jis ;exif.encode_jis = ; http://php.net/exif.decode-jis-motorola ;exif.decode_jis_motorola = JIS ; http://php.net/exif.decode-jis-intel ;exif.decode_jis_intel = JIS [Tidy] ; The path to a default tidy configuration file to use when using tidy ; http://php.net/tidy.default-config ;tidy.default_config = /usr/local/lib/php/default.tcfg ; Should tidy clean and repair output automatically? ; WARNING: Do not use this option if you are generating non-html content ; such as dynamic images ; http://php.net/tidy.clean-output tidy.clean_output = Off [soap] ; Enables or disables WSDL caching feature. ; http://php.net/soap.wsdl-cache-enabled soap.wsdl_cache_enabled=1 ; Sets the directory name where SOAP extension will put cache files. ; http://php.net/soap.wsdl-cache-dir soap.wsdl_cache_dir="/tmp" ; (time to live) Sets the number of second while cached file will be used ; instead of original one. ; http://php.net/soap.wsdl-cache-ttl soap.wsdl_cache_ttl=86400 ; Sets the size of the cache limit. (Max. number of WSDL files to cache) soap.wsdl_cache_limit = 5 [sysvshm] ; A default size of the shared memory segment ;sysvshm.init_mem = 10000 [ldap] ; Sets the maximum number of open links or -1 for unlimited. ldap.max_links = -1 [mcrypt] ; For more information about mcrypt settings see http://php.net/mcrypt-module-open ; Directory where to load mcrypt algorithms ; Default: Compiled in into libmcrypt (usually /usr/local/lib/libmcrypt) ;mcrypt.algorithms_dir= ; Directory where to load mcrypt modes ; Default: Compiled in into libmcrypt (usually /usr/local/lib/libmcrypt) ;mcrypt.modes_dir= [dba] ;dba.default_handler= [curl] ; A default value for the CURLOPT_CAINFO option. This is required to be an ; absolute path. ;curl.cainfo = ; Local Variables: ; tab-width: 4 ; End:
Computer Networking: A Top-Down Approach, 6th Edition Solutions to Review Questions and Problems Version Date: May 2012 This document contains the solutions to review questions and problems for the 5th edition of Computer Networking: A Top-Down Approach by Jim Kurose and Keith Ross. These solutions are being made available to instructors ONLY. Please do NOT copy or distribute this document to others (even other instructors). Please do not post any solutions on a publicly-available Web site. We’ll be happy to provide a copy (up-to-date) of this solution manual ourselves to anyone who asks. Acknowledgments: Over the years, several students and colleagues have helped us prepare this solutions manual. Special thanks goes to HongGang Zhang, Rakesh Kumar, Prithula Dhungel, and Vijay Annapureddy. Also thanks to all the readers who have made suggestions and corrected errors. All material © copyright 1996-2012 by J.F. Kurose and K.W. Ross. All rights reserved Chapter 1 Review Questions There is no difference. Throughout this text, the words “host” and “end system” are used interchangeably. End systems include PCs, workstations, Web servers, mail servers, PDAs, Internet-connected game consoles, etc. From Wikipedia: Diplomatic protocol is commonly described as a set of international courtesy rules. These well-established and time-honored rules have made it easier for nations and people to live and work together. Part of protocol has always been the acknowledgment of the hierarchical standing of all present. Protocol rules are based on the principles of civility. Standards are important for protocols so that people can create networking systems and products that interoperate. 1. Dial-up modem over telephone line: home; 2. DSL over telephone line: home or small office; 3. Cable to HFC: home; 4. 100 Mbps switched Ethernet: enterprise; 5. Wifi (802.11): home and enterprise: 6. 3G and 4G: wide-area wireless. HFC bandwidth is shared among the users. On the downstream channel, all packets emanate from a single source, namely, the head end. Thus, there are no collisions in the downstream channel. In most American cities, the current possibilities include: dial-up; DSL; cable modem; fiber-to-the-home. 7. Ethernet LANs have transmission rates of 10 Mbps, 100 Mbps, 1 Gbps and 10 Gbps. 8. Today, Ethernet most commonly runs over twisted-pair copper wire. It also can run over fibers optic links. 9. Dial up modems: up to 56 Kbps, bandwidth is dedicated; ADSL: up to 24 Mbps downstream and 2.5 Mbps upstream, bandwidth is dedicated; HFC, rates up to 42.8 Mbps and upstream rates of up to 30.7 Mbps, bandwidth is shared. FTTH: 2-10Mbps upload; 10-20 Mbps download; bandwidth is not shared. 10. There are two popular wireless Internet access technologies today: Wifi (802.11) In a wireless LAN, wireless users transmit/receive packets to/from an base station (i.e., wireless access point) within a radius of few tens of meters. The base station is typically connected to the wired Internet and thus serves to connect wireless users to the wired network. 3G and 4G wide-area wireless access networks. In these systems, packets are transmitted over the same wireless infrastructure used for cellular telephony, with the base station thus being managed by a telecommunications provider. This provides wireless access to users within a radius of tens of kilometers of the base station. 11. At time t0 the sending host begins to transmit. At time t1 = L/R1, the sending host completes transmission and the entire packet is received at the router (no propagation delay). Because the router has the entire packet at time t1, it can begin to transmit the packet to the receiving host at time t1. At time t2 = t1 + L/R2, the router completes transmission and the entire packet is received at the receiving host (again, no propagation delay). Thus, the end-to-end delay is L/R1 + L/R2. 12. A circuit-switched network can guarantee a certain amount of end-to-end bandwidth for the duration of a call. Most packet-switched networks today (including the Internet) cannot make any end-to-end guarantees for bandwidth. FDM requires sophisticated analog hardware to shift signal into appropriate frequency bands. 13. a) 2 users can be supported because each user requires half of the link bandwidth. b) Since each user requires 1Mbps when transmitting, if two or fewer users transmit simultaneously, a maximum of 2Mbps will be required. Since the available bandwidth of the shared link is 2Mbps, there will be no queuing delay before the link. Whereas, if three users transmit simultaneously, the bandwidth required will be 3Mbps which is more than the available bandwidth of the shared link. In this case, there will be queuing delay before the link. c) Probability that a given user is transmitting = 0.2 d) Probability that all three users are transmitting simultaneously = = (0.2)3 = 0.008. Since the queue grows when all the users are transmitting, the fraction of time during which the queue grows (which is equal to the probability that all three users are transmitting simultaneously) is 0.008. 14. If the two ISPs do not peer with each other, then when they send traffic to each other they have to send the traffic through a provider ISP (intermediary), to which they have to pay for carrying the traffic. By peering with each other directly, the two ISPs can reduce their payments to their provider ISPs. An Internet Exchange Points (IXP) (typically in a standalone building with its own switches) is a meeting point where multiple ISPs can connect and/or peer together. An ISP earns its money by charging each of the the ISPs that connect to the IXP a relatively small fee, which may depend on the amount of traffic sent to or received from the IXP. 15. Google's private network connects together all its data centers, big and small. Traffic between the Google data centers passes over its private network rather than over the public Internet. Many of these data centers are located in, or close to, lower tier ISPs. Therefore, when Google delivers content to a user, it often can bypass higher tier ISPs. What motivates content providers to create these networks? First, the content provider has more control over the user experience, since it has to use few intermediary ISPs. Second, it can save money by sending less traffic into provider networks. Third, if ISPs decide to charge more money to highly profitable content providers (in countries where net neutrality doesn't apply), the content providers can avoid these extra payments. 16. The delay components are processing delays, transmission delays, propagation delays, and queuing delays. All of these delays are fixed, except for the queuing delays, which are variable. 17. a) 1000 km, 1 Mbps, 100 bytes b) 100 km, 1 Mbps, 100 bytes 18. 10msec; d/s; no; no 19. a) 500 kbps b) 64 seconds c) 100kbps; 320 seconds 20. End system A breaks the large file into chunks. It adds header to each chunk, thereby generating multiple packets from the file. The header in each packet includes the IP address of the destination (end system B). The packet switch uses the destination IP address in the packet to determine the outgoing link. Asking which road to take is analogous to a packet asking which outgoing link it should be forwarded on, given the packet’s destination address. 21. The maximum emission rate is 500 packets/sec and the maximum transmission rate is 350 packets/sec. The corresponding traffic intensity is 500/350 =1.43 > 1. Loss will eventually occur for each experiment; but the time when loss first occurs will be different from one experiment to the next due to the randomness in the emission process. 22. Five generic tasks are error control, flow control, segmentation and reassembly, multiplexing, and connection setup. Yes, these tasks can be duplicated at different layers. For example, error control is often provided at more than one layer. 23. The five layers in the Internet protocol stack are – from top to bottom – the application layer, the transport layer, the network layer, the link layer, and the physical layer. The principal responsibilities are outlined in Section 1.5.1. 24. Application-layer message: data which an application wants to send and passed onto the transport layer; transport-layer segment: generated by the transport layer and encapsulates application-layer message with transport layer header; network-layer datagram: encapsulates transport-layer segment with a network-layer header; link-layer frame: encapsulates network-layer datagram with a link-layer header. 25. Routers process network, link and physical layers (layers 1 through 3). (This is a little bit of a white lie, as modern routers sometimes act as firewalls or caching components, and process Transport layer as well.) Link layer switches process link and physical layers (layers 1 through2). Hosts process all five layers. 26. a) Virus Requires some form of human interaction to spread. Classic example: E-mail viruses. b) Worms No user replication needed. Worm in infected host scans IP addresses and port numbers, looking for vulnerable processes to infect. 27. Creation of a botnet requires an attacker to find vulnerability in some application or system (e.g. exploiting the buffer overflow vulnerability that might exist in an application). After finding the vulnerability, the attacker needs to scan for hosts that are vulnerable. The target is basically to compromise a series of systems by exploiting that particular vulnerability. Any system that is part of the botnet can automatically scan its environment and propagate by exploiting the vulnerability. An important property of such botnets is that the originator of the botnet can remotely control and issue commands to all the nodes in the botnet. Hence, it becomes possible for the attacker to issue a command to all the nodes, that target a single node (for example, all nodes in the botnet might be commanded by the attacker to send a TCP SYN message to the target, which might result in a TCP SYN flood attack at the target). 28. Trudy can pretend to be Bob to Alice (and vice-versa) and partially or completely modify the message(s) being sent from Bob to Alice. For example, she can easily change the phrase “Alice, I owe you $1000” to “Alice, I owe you $10,000”. Furthermore, Trudy can even drop the packets that are being sent by Bob to Alice (and vise-versa), even if the packets from Bob to Alice are encrypted. Chapter 1 Problems Problem 1 There is no single right answer to this question. Many protocols would do the trick. Here's a simple answer below: Messages from ATM machine to Server Msg name purpose -------- ------- HELO Let server know that there is a card in the ATM machine ATM card transmits user ID to Server PASSWD User enters PIN, which is sent to server BALANCE User requests balance WITHDRAWL User asks to withdraw money BYE user all done Messages from Server to ATM machine (display) Msg name purpose -------- ------- PASSWD Ask user for PIN (password) OK last requested operation (PASSWD, WITHDRAWL) OK ERR last requested operation (PASSWD, WITHDRAWL) in ERROR AMOUNT sent in response to BALANCE request BYE user done, display welcome screen at ATM Correct operation: client server HELO (userid) --------------> (check if valid userid) <------------- PASSWD PASSWD --------------> (check password) <------------- AMOUNT WITHDRAWL --------------> check if enough $ to cover withdrawl (check if valid userid) <------------- PASSWD PASSWD --------------> (check password) <------------- AMOUNT WITHDRAWL --------------> check if enough $ to cover withdrawl <------------- BYE Problem 2 At time N*(L/R) the first packet has reached the destination, the second packet is stored in the last router, the third packet is stored in the next-to-last router, etc. At time N*(L/R) + L/R, the second packet has reached the destination, the third packet is stored in the last router, etc. Continuing with this logic, we see that at time N*(L/R) + (P-1)*(L/R) = (N+P-1)*(L/R) all packets have reached the destination. Problem 3 a) A circuit-switched network would be well suited to the application, because the application involves long sessions with predictable smooth bandwidth requirements. Since the transmission rate is known and not bursty, bandwidth can be reserved for each application session without significant waste. In addition, the overhead costs of setting up and tearing down connections are amortized over the lengthy duration of a typical application session. b) In the worst case, all the applications simultaneously transmit over one or more network links. However, since each link has sufficient bandwidth to handle the sum of all of the applications' data rates, no congestion (very little queuing) will occur. Given such generous link capacities, the network does not need congestion control mechanisms. Problem 4 Between the switch in the upper left and the switch in the upper right we can have 4 connections. Similarly we can have four connections between each of the 3 other pairs of adjacent switches. Thus, this network can support up to 16 connections. We can 4 connections passing through the switch in the upper-right-hand corner and another 4 connections passing through the switch in the lower-left-hand corner, giving a total of 8 connections. Yes. For the connections between A and C, we route two connections through B and two connections through D. For the connections between B and D, we route two connections through A and two connections through C. In this manner, there are at most 4 connections passing through any link. Problem 5 Tollbooths are 75 km apart, and the cars propagate at 100km/hr. A tollbooth services a car at a rate of one car every 12 seconds. a) There are ten cars. It takes 120 seconds, or 2 minutes, for the first tollbooth to service the 10 cars. Each of these cars has a propagation delay of 45 minutes (travel 75 km) before arriving at the second tollbooth. Thus, all the cars are lined up before the second tollbooth after 47 minutes. The whole process repeats itself for traveling between the second and third tollbooths. It also takes 2 minutes for the third tollbooth to service the 10 cars. Thus the total delay is 96 minutes. b) Delay between tollbooths is 8*12 seconds plus 45 minutes, i.e., 46 minutes and 36 seconds. The total delay is twice this amount plus 8*12 seconds, i.e., 94 minutes and 48 seconds. Problem 6 a) seconds. b) seconds. c) seconds. d) The bit is just leaving Host A. e) The first bit is in the link and has not reached Host B. f) The first bit has reached Host B. g) Want km. Problem 7 Consider the first bit in a packet. Before this bit can be transmitted, all of the bits in the packet must be generated. This requires sec=7msec. The time required to transmit the packet is sec= sec. Propagation delay = 10 msec. The delay until decoding is 7msec + sec + 10msec = 17.224msec A similar analysis shows that all bits experience a delay of 17.224 msec. Problem 8 a) 20 users can be supported. b) . c) . d) . We use the central limit theorem to approximate this probability. Let be independent random variables such that . “21 or more users” when is a standard normal r.v. Thus “21 or more users” . Problem 9 10,000 Problem 10 The first end system requires L/R1 to transmit the packet onto the first link; the packet propagates over the first link in d1/s1; the packet switch adds a processing delay of dproc; after receiving the entire packet, the packet switch connecting the first and the second link requires L/R2 to transmit the packet onto the second link; the packet propagates over the second link in d2/s2. Similarly, we can find the delay caused by the second switch and the third link: L/R3, dproc, and d3/s3. Adding these five delays gives dend-end = L/R1 + L/R2 + L/R3 + d1/s1 + d2/s2 + d3/s3+ dproc+ dproc To answer the second question, we simply plug the values into the equation to get 6 + 6 + 6 + 20+16 + 4 + 3 + 3 = 64 msec. Problem 11 Because bits are immediately transmitted, the packet switch does not introduce any delay; in particular, it does not introduce a transmission delay. Thus, dend-end = L/R + d1/s1 + d2/s2+ d3/s3 For the values in Problem 10, we get 6 + 20 + 16 + 4 = 46 msec. Problem 12 The arriving packet must first wait for the link to transmit 4.5 *1,500 bytes = 6,750 bytes or 54,000 bits. Since these bits are transmitted at 2 Mbps, the queuing delay is 27 msec. Generally, the queuing delay is (nL + (L - x))/R. Problem 13 The queuing delay is 0 for the first transmitted packet, L/R for the second transmitted packet, and generally, (n-1)L/R for the nth transmitted packet. Thus, the average delay for the N packets is: (L/R + 2L/R + ....... + (N-1)L/R)/N = L/(RN) * (1 + 2 + ..... + (N-1)) = L/(RN) * N(N-1)/2 = LN(N-1)/(2RN) = (N-1)L/(2R) Note that here we used the well-known fact: 1 + 2 + ....... + N = N(N+1)/2 It takes seconds to transmit the packets. Thus, the buffer is empty when a each batch of packets arrive. Thus, the average delay of a packet across all batches is the average delay within one batch, i.e., (N-1)L/2R. Problem 14 The transmission delay is . The total delay is Let . Total delay = For x=0, the total delay =0; as we increase x, total delay increases, approaching infinity as x approaches 1/a. Problem 15 Total delay . Problem 16 The total number of packets in the system includes those in the buffer and the packet that is being transmitted. So, N=10+1. Because , so (10+1)=a*(queuing delay + transmission delay). That is, 11=a*(0.01+1/100)=a*(0.01+0.01). Thus, a=550 packets/sec. Problem 17 There are nodes (the source host and the routers). Let denote the processing delay at the th node. Let be the transmission rate of the th link and let . Let be the propagation delay across the th link. Then . Let denote the average queuing delay at node . Then . Problem 18 On linux you can use the command traceroute www.targethost.com and in the Windows command prompt you can use tracert www.targethost.com In either case, you will get three delay measurements. For those three measurements you can calculate the mean and standard deviation. Repeat the experiment at different times of the day and comment on any changes. Here is an example solution: Traceroutes between San Diego Super Computer Center and www.poly.edu The average (mean) of the round-trip delays at each of the three hours is 71.18 ms, 71.38 ms and 71.55 ms, respectively. The standard deviations are 0.075 ms, 0.21 ms, 0.05 ms, respectively. In this example, the traceroutes have 12 routers in the path at each of the three hours. No, the paths didn’t change during any of the hours. Traceroute packets passed through four ISP networks from source to destination. Yes, in this experiment the largest delays occurred at peering interfaces between adjacent ISPs. Traceroutes from www.stella-net.net (France) to www.poly.edu (USA). The average round-trip delays at each of the three hours are 87.09 ms, 86.35 ms and 86.48 ms, respectively. The standard deviations are 0.53 ms, 0.18 ms, 0.23 ms, respectively. In this example, there are 11 routers in the path at each of the three hours. No, the paths didn’t change during any of the hours. Traceroute packets passed three ISP networks from source to destination. Yes, in this experiment the largest delays occurred at peering interfaces between adjacent ISPs. Problem 19 An example solution: Traceroutes from two different cities in France to New York City in United States In these traceroutes from two different cities in France to the same destination host in United States, seven links are in common including the transatlantic link. In this example of traceroutes from one city in France and from another city in Germany to the same host in United States, three links are in common including the transatlantic link. Traceroutes to two different cities in China from same host in United States Five links are common in the two traceroutes. The two traceroutes diverge before reaching China Problem 20 Throughput = min{Rs, Rc, R/M} Problem 21 If only use one path, the max throughput is given by: . If use all paths, the max throughput is given by . Problem 22 Probability of successfully receiving a packet is: ps= (1-p)N. The number of transmissions needed to be performed until the packet is successfully received by the client is a geometric random variable with success probability ps. Thus, the average number of transmissions needed is given by: 1/ps . Then, the average number of re-transmissions needed is given by: 1/ps -1. Problem 23 Let’s call the first packet A and call the second packet B. If the bottleneck link is the first link, then packet B is queued at the first link waiting for the transmission of packet A. So the packet inter-arrival time at the destination is simply L/Rs. If the second link is the bottleneck link and both packets are sent back to back, it must be true that the second packet arrives at the input queue of the second link before the second link finishes the transmission of the first packet. That is, L/Rs + L/Rs + dprop = L/Rs + dprop + L/Rc Thus, the minimum value of T is L/Rc  L/Rs . Problem 24 40 terabytes = 40 * 1012 * 8 bits. So, if using the dedicated link, it will take 40 * 1012 * 8 / (100 *106 ) =3200000 seconds = 37 days. But with FedEx overnight delivery, you can guarantee the data arrives in one day, and it should cost less than $100. Problem 25 160,000 bits 160,000 bits The bandwidth-delay product of a link is the maximum number of bits that can be in the link. the width of a bit = length of link / bandwidth-delay product, so 1 bit is 125 meters long, which is longer than a football field s/R Problem 26 s/R=20000km, then R=s/20000km= 2.5*108/(2*107)= 12.5 bps Problem 27 80,000,000 bits 800,000 bits, this is because that the maximum number of bits that will be in the link at any given time = min(bandwidth delay product, packet size) = 800,000 bits. .25 meters Problem 28 ttrans + tprop = 400 msec + 80 msec = 480 msec. 20 * (ttrans + 2 tprop) = 20*(20 msec + 80 msec) = 2 sec. Breaking up a file takes longer to transmit because each data packet and its corresponding acknowledgement packet add their own propagation delays. Problem 29 Recall geostationary satellite is 36,000 kilometers away from earth surface. 150 msec 1,500,000 bits 600,000,000 bits Problem 30 Let’s suppose the passenger and his/her bags correspond to the data unit arriving to the top of the protocol stack. When the passenger checks in, his/her bags are checked, and a tag is attached to the bags and ticket. This is additional information added in the Baggage layer if Figure 1.20 that allows the Baggage layer to implement the service or separating the passengers and baggage on the sending side, and then reuniting them (hopefully!) on the destination side. When a passenger then passes through security and additional stamp is often added to his/her ticket, indicating that the passenger has passed through a security check. This information is used to ensure (e.g., by later checks for the security information) secure transfer of people. Problem 31 Time to send message from source host to first packet switch = With store-and-forward switching, the total time to move message from source host to destination host = Time to send 1st packet from source host to first packet switch = . . Time at which 2nd packet is received at the first switch = time at which 1st packet is received at the second switch = Time at which 1st packet is received at the destination host = . After this, every 5msec one packet will be received; thus time at which last (800th) packet is received = . It can be seen that delay in using message segmentation is significantly less (almost 1/3rd). Without message segmentation, if bit errors are not tolerated, if there is a single bit error, the whole message has to be retransmitted (rather than a single packet). Without message segmentation, huge packets (containing HD videos, for example) are sent into the network. Routers have to accommodate these huge packets. Smaller packets have to queue behind enormous packets and suffer unfair delays. Packets have to be put in sequence at the destination. Message segmentation results in many smaller packets. Since header size is usually the same for all packets regardless of their size, with message segmentation the total amount of header bytes is more. Problem 32 Yes, the delays in the applet correspond to the delays in the Problem 31.The propagation delays affect the overall end-to-end delays both for packet switching and message switching equally. Problem 33 There are F/S packets. Each packet is S=80 bits. Time at which the last packet is received at the first router is sec. At this time, the first F/S-2 packets are at the destination, and the F/S-1 packet is at the second router. The last packet must then be transmitted by the first router and the second router, with each transmission taking sec. Thus delay in sending the whole file is To calculate the value of S which leads to the minimum delay, Problem 34 The circuit-switched telephone networks and the Internet are connected together at "gateways". When a Skype user (connected to the Internet) calls an ordinary telephone, a circuit is established between a gateway and the telephone user over the circuit switched network. The skype user's voice is sent in packets over the Internet to the gateway. At the gateway, the voice signal is reconstructed and then sent over the circuit. In the other direction, the voice signal is sent over the circuit switched network to the gateway. The gateway packetizes the voice signal and sends the voice packets to the Skype user.   Chapter 2 Review Questions The Web: HTTP; file transfer: FTP; remote login: Telnet; e-mail: SMTP; BitTorrent file sharing: BitTorrent protocol Network architecture refers to the organization of the communication process into layers (e.g., the five-layer Internet architecture). Application architecture, on the other hand, is designed by an application developer and dictates the broad structure of the application (e.g., client-server or P2P). The process which initiates the communication is the client; the process that waits to be contacted is the server. No. In a P2P file-sharing application, the peer that is receiving a file is typically the client and the peer that is sending the file is typically the server. The IP address of the destination host and the port number of the socket in the destination process. You would use UDP. With UDP, the transaction can be completed in one roundtrip time (RTT) - the client sends the transaction request into a UDP socket, and the server sends the reply back to the client's UDP socket. With TCP, a minimum of two RTTs are needed - one to set-up the TCP connection, and another for the client to send the request, and for the server to send back the reply. One such example is remote word processing, for example, with Google docs. However, because Google docs runs over the Internet (using TCP), timing guarantees are not provided. a) Reliable data transfer TCP provides a reliable byte-stream between client and server but UDP does not. b) A guarantee that a certain value for throughput will be maintained Neither c) A guarantee that data will be delivered within a specified amount of time Neither d) Confidentiality (via encryption) Neither SSL operates at the application layer. The SSL socket takes unencrypted data from the application layer, encrypts it and then passes it to the TCP socket. If the application developer wants TCP to be enhanced with SSL, she has to include the SSL code in the application. A protocol uses handshaking if the two communicating entities first exchange control packets before sending data to each other. SMTP uses handshaking at the application layer whereas HTTP does not. The applications associated with those protocols require that all application data be received in the correct order and without gaps. TCP provides this service whereas UDP does not. When the user first visits the site, the server creates a unique identification number, creates an entry in its back-end database, and returns this identification number as a cookie number. This cookie number is stored on the user’s host and is managed by the browser. During each subsequent visit (and purchase), the browser sends the cookie number back to the site. Thus the site knows when this user (more precisely, this browser) is visiting the site. Web caching can bring the desired content “closer” to the user, possibly to the same LAN to which the user’s host is connected. Web caching can reduce the delay for all objects, even objects that are not cached, since caching reduces the traffic on links. Telnet is not available in Windows 7 by default. to make it available, go to Control Panel, Programs and Features, Turn Windows Features On or Off, Check Telnet client. To start Telnet, in Windows command prompt, issue the following command > telnet webserverver 80 where "webserver" is some webserver. After issuing the command, you have established a TCP connection between your client telnet program and the web server. Then type in an HTTP GET message. An example is given below: Since the index.html page in this web server was not modified since Fri, 18 May 2007 09:23:34 GMT, and the above commands were issued on Sat, 19 May 2007, the server returned "304 Not Modified". Note that the first 4 lines are the GET message and header lines inputed by the user, and the next 4 lines (starting from HTTP/1.1 304 Not Modified) is the response from the web server. FTP uses two parallel TCP connections, one connection for sending control information (such as a request to transfer a file) and another connection for actually transferring the file. Because the control information is not sent over the same connection that the file is sent over, FTP sends control information out of band. The message is first sent from Alice’s host to her mail server over HTTP. Alice’s mail server then sends the message to Bob’s mail server over SMTP. Bob then transfers the message from his mail server to his host over POP3. 17. Received: from 65.54.246.203 (EHLO bay0-omc3-s3.bay0.hotmail.com) (65.54.246.203) by mta419.mail.mud.yahoo.com with SMTP; Sat, 19 May 2007 16:53:51 -0700 Received: from hotmail.com ([65.55.135.106]) by bay0-omc3-s3.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.2668); Sat, 19 May 2007 16:52:42 -0700 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sat, 19 May 2007 16:52:41 -0700 Message-ID: Received: from 65.55.135.123 by by130fd.bay130.hotmail.msn.com with HTTP; Sat, 19 May 2007 23:52:36 GMT From: "prithula dhungel" To: prithula@yahoo.com Bcc: Subject: Test mail Date: Sat, 19 May 2007 23:52:36 +0000 Mime-Version: 1.0 Content-Type: Text/html; format=flowed Return-Path: prithuladhungel@hotmail.com Figure: A sample mail message header Received: This header field indicates the sequence in which the SMTP servers send and receive the mail message including the respective timestamps. In this example there are 4 “Received:” header lines. This means the mail message passed through 5 different SMTP servers before being delivered to the receiver’s mail box. The last (forth) “Received:” header indicates the mail message flow from the SMTP server of the sender to the second SMTP server in the chain of servers. The sender’s SMTP server is at address 65.55.135.123 and the second SMTP server in the chain is by130fd.bay130.hotmail.msn.com. The third “Received:” header indicates the mail message flow from the second SMTP server in the chain to the third server, and so on. Finally, the first “Received:” header indicates the flow of the mail messages from the forth SMTP server to the last SMTP server (i.e. the receiver’s mail server) in the chain. Message-id: The message has been given this number BAY130-F26D9E35BF59E0D18A819AFB9310@phx.gbl (by bay0-omc3-s3.bay0.hotmail.com. Message-id is a unique string assigned by the mail system when the message is first created. From: This indicates the email address of the sender of the mail. In the given example, the sender is “prithuladhungel@hotmail.com” To: This field indicates the email address of the receiver of the mail. In the example, the receiver is “prithula@yahoo.com” Subject: This gives the subject of the mail (if any specified by the sender). In the example, the subject specified by the sender is “Test mail” Date: The date and time when the mail was sent by the sender. In the example, the sender sent the mail on 19th May 2007, at time 23:52:36 GMT. Mime-version: MIME version used for the mail. In the example, it is 1.0. Content-type: The type of content in the body of the mail message. In the example, it is “text/html”. Return-Path: This specifies the email address to which the mail will be sent if the receiver of this mail wants to reply to the sender. This is also used by the sender’s mail server for bouncing back undeliverable mail messages of mailer-daemon error messages. In the example, the return path is “prithuladhungel@hotmail.com”. With download and delete, after a user retrieves its messages from a POP server, the messages are deleted. This poses a problem for the nomadic user, who may want to access the messages from many different machines (office PC, home PC, etc.). In the download and keep configuration, messages are not deleted after the user retrieves the messages. This can also be inconvenient, as each time the user retrieves the stored messages from a new machine, all of non-deleted messages will be transferred to the new machine (including very old messages). Yes an organization’s mail server and Web server can have the same alias for a host name. The MX record is used to map the mail server’s host name to its IP address. You should be able to see the sender's IP address for a user with an .edu email address. But you will not be able to see the sender's IP address if the user uses a gmail account. It is not necessary that Bob will also provide chunks to Alice. Alice has to be in the top 4 neighbors of Bob for Bob to send out chunks to her; this might not occur even if Alice provides chunks to Bob throughout a 30-second interval. Recall that in BitTorrent, a peer picks a random peer and optimistically unchokes the peer for a short period of time. Therefore, Alice will eventually be optimistically unchoked by one of her neighbors, during which time she will receive chunks from that neighbor. The overlay network in a P2P file sharing system consists of the nodes participating in the file sharing system and the logical links between the nodes. There is a logical link (an “edge” in graph theory terms) from node A to node B if there is a semi-permanent TCP connection between A and B. An overlay network does not include routers. Mesh DHT: The advantage is in order to a route a message to the peer (with ID) that is closest to the key, only one hop is required; the disadvantage is that each peer must track all other peers in the DHT. Circular DHT: the advantage is that each peer needs to track only a few other peers; the disadvantage is that O(N) hops are needed to route a message to the peer that is closest to the key. 25. File Distribution Instant Messaging Video Streaming Distributed Computing With the UDP server, there is no welcoming socket, and all data from different clients enters the server through this one socket. With the TCP server, there is a welcoming socket, and each time a client initiates a connection to the server, a new socket is created. Thus, to support n simultaneous connections, the server would need n+1 sockets. For the TCP application, as soon as the client is executed, it attempts to initiate a TCP connection with the server. If the TCP server is not running, then the client will fail to make a connection. For the UDP application, the client does not initiate connections (or attempt to communicate with the UDP server) immediately upon execution Chapter 2 Problems Problem 1 a) F b) T c) F d) F e) F Problem 2 Access control commands: USER, PASS, ACT, CWD, CDUP, SMNT, REIN, QUIT. Transfer parameter commands: PORT, PASV, TYPE STRU, MODE. Service commands: RETR, STOR, STOU, APPE, ALLO, REST, RNFR, RNTO, ABOR, DELE, RMD, MRD, PWD, LIST, NLST, SITE, SYST, STAT, HELP, NOOP. Problem 3 Application layer protocols: DNS and HTTP Transport layer protocols: UDP for DNS; TCP for HTTP Problem 4 The document request was http://gaia.cs.umass.edu/cs453/index.html. The Host : field indicates the server's name and /cs453/index.html indicates the file name. The browser is running HTTP version 1.1, as indicated just before the first pair. The browser is requesting a persistent connection, as indicated by the Connection: keep-alive. This is a trick question. This information is not contained in an HTTP message anywhere. So there is no way to tell this from looking at the exchange of HTTP messages alone. One would need information from the IP datagrams (that carried the TCP segment that carried the HTTP GET request) to answer this question. Mozilla/5.0. The browser type information is needed by the server to send different versions of the same object to different types of browsers. Problem 5 The status code of 200 and the phrase OK indicate that the server was able to locate the document successfully. The reply was provided on Tuesday, 07 Mar 2008 12:39:45 Greenwich Mean Time. The document index.html was last modified on Saturday 10 Dec 2005 18:27:46 GMT. There are 3874 bytes in the document being returned. The first five bytes of the returned document are : ed to a persistent connection, as indicated by the Connection: Keep-Alive field Problem 6 Persistent connections are discussed in section 8 of RFC 2616 (the real goal of this question was to get you to retrieve and read an RFC). Sections 8.1.2 and 8.1.2.1 of the RFC indicate that either the client or the server can indicate to the other that it is going to close the persistent connection. It does so by including the connection-token "close" in the Connection-header field of the http request/reply. HTTP does not provide any encryption services. (From RFC 2616) “Clients that use persistent connections should limit the number of simultaneous connections that they maintain to a given server. A single-user client SHOULD NOT maintain more than 2 connections with any server or proxy.” Yes. (From RFC 2616) “A client might have started to send a new request at the same time that the server has decided to close the "idle" connection. From the server's point of view, the connection is being closed while it was idle, but from the client's point of view, a request is in progress.” Problem 7 The total amount of time to get the IP address is . Once the IP address is known, elapses to set up the TCP connection and another elapses to request and receive the small object. The total response time is Problem 8 . . Problem 9 The time to transmit an object of size L over a link or rate R is L/R. The average time is the average size of the object divided by R:  = (850,000 bits)/(15,000,000 bits/sec) = .0567 sec The traffic intensity on the link is given by =(16 requests/sec)(.0567 sec/request) = 0.907. Thus, the average access delay is (.0567 sec)/(1 - .907)  .6 seconds. The total average response time is therefore .6 sec + 3 sec = 3.6 sec. The traffic intensity on the access link is reduced by 60% since the 60% of the requests are satisfied within the institutional network. Thus the average access delay is (.0567 sec)/[1 – (.4)(.907)] = .089 seconds. The response time is approximately zero if the request is satisfied by the cache (which happens with probability .6); the average response time is .089 sec + 3 sec = 3.089 sec for cache misses (which happens 40% of the time). So the average response time is (.6)(0 sec) + (.4)(3.089 sec) = 1.24 seconds. Thus the average response time is reduced from 3.6 sec to 1.24 sec. Problem 10 Note that each downloaded object can be completely put into one data packet. Let Tp denote the one-way propagation delay between the client and the server. First consider parallel downloads using non-persistent connections. Parallel downloads would allow 10 connections to share the 150 bits/sec bandwidth, giving each just 15 bits/sec. Thus, the total time needed to receive all objects is given by: (200/150+Tp + 200/150 +Tp + 200/150+Tp + 100,000/150+ Tp ) + (200/(150/10)+Tp + 200/(150/10) +Tp + 200/(150/10)+Tp + 100,000/(150/10)+ Tp ) = 7377 + 8*Tp (seconds) Now consider a persistent HTTP connection. The total time needed is given by: (200/150+Tp + 200/150 +Tp + 200/150+Tp + 100,000/150+ Tp ) + 10*(200/150+Tp + 100,000/150+ Tp ) =7351 + 24*Tp (seconds) Assuming the speed of light is 300*106 m/sec, then Tp=10/(300*106)=0.03 microsec. Tp is therefore negligible compared with transmission delay. Thus, we see that persistent HTTP is not significantly faster (less than 1 percent) than the non-persistent case with parallel download. Problem 11 Yes, because Bob has more connections, he can get a larger share of the link bandwidth. Yes, Bob still needs to perform parallel downloads; otherwise he will get less bandwidth than the other four users. Problem 12 Server.py from socket import * serverPort=12000 serverSocket=socket(AF_INET,SOCK_STREAM) serverSocket.bind(('',serverPort)) serverSocket.listen(1) connectionSocket, addr = serverSocket.accept() while 1: sentence = connectionSocket.recv(1024) print 'From Server:', sentence, '\n' serverSocket.close() Problem 13 The MAIL FROM: in SMTP is a message from the SMTP client that identifies the sender of the mail message to the SMTP server. The From: on the mail message itself is NOT an SMTP message, but rather is just a line in the body of the mail message. Problem 14 SMTP uses a line containing only a period to mark the end of a message body. HTTP uses “Content-Length header field” to indicate the length of a message body. No, HTTP cannot use the method used by SMTP, because HTTP message could be binary data, whereas in SMTP, the message body must be in 7-bit ASCII format. Problem 15 MTA stands for Mail Transfer Agent. A host sends the message to an MTA. The message then follows a sequence of MTAs to reach the receiver’s mail reader. We see that this spam message follows a chain of MTAs. An honest MTA should report where it receives the message. Notice that in this message, “asusus-4b96 ([58.88.21.177])” does not report from where it received the email. Since we assume only the originator is dishonest, so “asusus-4b96 ([58.88.21.177])” must be the originator. Problem 16 UIDL abbreviates “unique-ID listing”. When a POP3 client issues the UIDL command, the server responds with the unique message ID for all of the messages present in the user's mailbox. This command is useful for “download and keep”. By maintaining a file that lists the messages retrieved during earlier sessions, the client can use the UIDL command to determine which messages on the server have already been seen. Problem 17 a) C: dele 1 C: retr 2 S: (blah blah … S: ………..blah) S: . C: dele 2 C: quit S: +OK POP3 server signing off b) C: retr 2 S: blah blah … S: ………..blah S: . C: quit S: +OK POP3 server signing off C: list S: 1 498 S: 2 912 S: . C: retr 1 S: blah ….. S: ….blah S: . C: retr 2 S: blah blah … S: ………..blah S: . C: quit S: +OK POP3 server signing off Problem 18 For a given input of domain name (such as ccn.com), IP address or network administrator name, the whois database can be used to locate the corresponding registrar, whois server, DNS server, and so on. NS4.YAHOO.COM from www.register.com; NS1.MSFT.NET from ww.register.com Local Domain: www.mindspring.com Web servers : www.mindspring.com 207.69.189.21, 207.69.189.22, 207.69.189.23, 207.69.189.24, 207.69.189.25, 207.69.189.26, 207.69.189.27, 207.69.189.28 Mail Servers : mx1.mindspring.com (207.69.189.217) mx2.mindspring.com (207.69.189.218) mx3.mindspring.com (207.69.189.219) mx4.mindspring.com (207.69.189.220) Name Servers: itchy.earthlink.net (207.69.188.196) scratchy.earthlink.net (207.69.188.197) www.yahoo.com Web Servers: www.yahoo.com (216.109.112.135, 66.94.234.13) Mail Servers: a.mx.mail.yahoo.com (209.191.118.103) b.mx.mail.yahoo.com (66.196.97.250) c.mx.mail.yahoo.com (68.142.237.182, 216.39.53.3) d.mx.mail.yahoo.com (216.39.53.2) e.mx.mail.yahoo.com (216.39.53.1) f.mx.mail.yahoo.com (209.191.88.247, 68.142.202.247) g.mx.mail.yahoo.com (209.191.88.239, 206.190.53.191) Name Servers: ns1.yahoo.com (66.218.71.63) ns2.yahoo.com (68.142.255.16) ns3.yahoo.com (217.12.4.104) ns4.yahoo.com (68.142.196.63) ns5.yahoo.com (216.109.116.17) ns8.yahoo.com (202.165.104.22) ns9.yahoo.com (202.160.176.146) www.hotmail.com Web Servers: www.hotmail.com (64.4.33.7, 64.4.32.7) Mail Servers: mx1.hotmail.com (65.54.245.8, 65.54.244.8, 65.54.244.136) mx2.hotmail.com (65.54.244.40, 65.54.244.168, 65.54.245.40) mx3.hotmail.com (65.54.244.72, 65.54.244.200, 65.54.245.72) mx4.hotmail.com (65.54.244.232, 65.54.245.104, 65.54.244.104) Name Servers: ns1.msft.net (207.68.160.190) ns2.msft.net (65.54.240.126) ns3.msft.net (213.199.161.77) ns4.msft.net (207.46.66.126) ns5.msft.net (65.55.238.126) d) The yahoo web server has multiple IP addresses www.yahoo.com (216.109.112.135, 66.94.234.13) e) The address range for Polytechnic University: 128.238.0.0 – 128.238.255.255 f) An attacker can use the whois database and nslookup tool to determine the IP address ranges, DNS server addresses, etc., for the target institution. By analyzing the source address of attack packets, the victim can use whois to obtain information about domain from which the attack is coming and possibly inform the administrators of the origin domain. Problem 19 The following delegation chain is used for gaia.cs.umass.edu a.root-servers.net E.GTLD-SERVERS.NET ns1.umass.edu(authoritative) First command: dig +norecurse @a.root-servers.net any gaia.cs.umass.edu ;; AUTHORITY SECTION: edu. 172800 IN NS E.GTLD-SERVERS.NET. edu. 172800 IN NS A.GTLD-SERVERS.NET. edu. 172800 IN NS G3.NSTLD.COM. edu. 172800 IN NS D.GTLD-SERVERS.NET. edu. 172800 IN NS H3.NSTLD.COM. edu. 172800 IN NS L3.NSTLD.COM. edu. 172800 IN NS M3.NSTLD.COM. edu. 172800 IN NS C.GTLD-SERVERS.NET. Among all returned edu DNS servers, we send a query to the first one. dig +norecurse @E.GTLD-SERVERS.NET any gaia.cs.umass.edu umass.edu. 172800 IN NS ns1.umass.edu. umass.edu. 172800 IN NS ns2.umass.edu. umass.edu. 172800 IN NS ns3.umass.edu. Among all three returned authoritative DNS servers, we send a query to the first one. dig +norecurse @ns1.umass.edu any gaia.cs.umass.edu gaia.cs.umass.edu. 21600 IN A 128.119.245.12 The answer for google.com could be: a.root-servers.net E.GTLD-SERVERS.NET ns1.google.com(authoritative) Problem 20 We can periodically take a snapshot of the DNS caches in the local DNS servers. The Web server that appears most frequently in the DNS caches is the most popular server. This is because if more users are interested in a Web server, then DNS requests for that server are more frequently sent by users. Thus, that Web server will appear in the DNS caches more frequently. For a complete measurement study, see: Craig E. Wills, Mikhail Mikhailov, Hao Shang “Inferring Relative Popularity of Internet Applications by Actively Querying DNS Caches”, in IMC'03, October 27­29, 2003, Miami Beach, Florida, USA Problem 21 Yes, we can use dig to query that Web site in the local DNS server. For example, “dig cnn.com” will return the query time for finding cnn.com. If cnn.com was just accessed a couple of seconds ago, an entry for cnn.com is cached in the local DNS cache, so the query time is 0 msec. Otherwise, the query time is large. Problem 22 For calculating the minimum distribution time for client-server distribution, we use the following formula: Dcs = max {NF/us, F/dmin} Similarly, for calculating the minimum distribution time for P2P distribution, we use the following formula: Where, F = 15 Gbits = 15 * 1024 Mbits us = 30 Mbps dmin = di = 2 Mbps Note, 300Kbps = 300/1024 Mbps. Client Server N 10 100 1000 u 300 Kbps 7680 51200 512000 700 Kbps 7680 51200 512000 2 Mbps 7680 51200 512000 Peer to Peer N 10 100 1000 u 300 Kbps 7680 25904 47559 700 Kbps 7680 15616 21525 2 Mbps 7680 7680 7680 Problem 23 Consider a distribution scheme in which the server sends the file to each client, in parallel, at a rate of a rate of us/N. Note that this rate is less than each of the client’s download rate, since by assumption us/N ≤ dmin. Thus each client can also receive at rate us/N. Since each client receives at rate us/N, the time for each client to receive the entire file is F/( us/N) = NF/ us. Since all the clients receive the file in NF/ us, the overall distribution time is also NF/ us. Consider a distribution scheme in which the server sends the file to each client, in parallel, at a rate of dmin. Note that the aggregate rate, N dmin, is less than the server’s link rate us, since by assumption us/N ≥ dmin. Since each client receives at rate dmin, the time for each client to receive the entire file is F/ dmin. Since all the clients receive the file in this time, the overall distribution time is also F/ dmin. From Section 2.6 we know that DCS ≥ max {NF/us, F/dmin} (Equation 1) Suppose that us/N ≤ dmin. Then from Equation 1 we have DCS ≥ NF/us . But from (a) we have DCS ≤ NF/us . Combining these two gives: DCS = NF/us when us/N ≤ dmin. (Equation 2) We can similarly show that: DCS =F/dmin when us/N ≥ dmin (Equation 3). Combining Equation 2 and Equation 3 gives the desired result. Problem 24 Define u = u1 + u2 + ….. + uN. By assumption us <= (us + u)/N Equation 1 Divide the file into N parts, with the ith part having size (ui/u)F. The server transmits the ith part to peer i at rate ri = (ui/u)us. Note that r1 + r2 + ….. + rN = us, so that the aggregate server rate does not exceed the link rate of the server. Also have each peer i forward the bits it receives to each of the N-1 peers at rate ri. The aggregate forwarding rate by peer i is (N-1)ri. We have (N-1)ri = (N-1)(usui)/u = (us + u)/N Equation 2 Let ri = ui/(N-1) and rN+1 = (us – u/(N-1))/N In this distribution scheme, the file is broken into N+1 parts. The server sends bits from the ith part to the ith peer (i = 1, …., N) at rate ri. Each peer i forwards the bits arriving at rate ri to each of the other N-1 peers. Additionally, the server sends bits from the (N+1) st part at rate rN+1 to each of the N peers. The peers do not forward the bits from the (N+1)st part. The aggregate send rate of the server is r1+ …. + rN + N rN+1 = u/(N-1) + us – u/(N-1) = us Thus, the server’s send rate does not exceed its link rate. The aggregate send rate of peer i is (N-1)ri = ui Thus, each peer’s send rate does not exceed its link rate. In this distribution scheme, peer i receives bits at an aggregate rate of Thus each peer receives the file in NF/(us+u). (For simplicity, we neglected to specify the size of the file part for i = 1, …., N+1. We now provide that here. Let Δ = (us+u)/N be the distribution time. For i = 1, …, N, the ith file part is Fi = ri Δ bits. The (N+1)st file part is FN+1 = rN+1 Δ bits. It is straightforward to show that F1+ ….. + FN+1 = F.) The solution to this part is similar to that of 17 (c). We know from section 2.6 that Combining this with a) and b) gives the desired result. Problem 25 There are N nodes in the overlay network. There are N(N-1)/2 edges. Problem 26 Yes. His first claim is possible, as long as there are enough peers staying in the swarm for a long enough time. Bob can always receive data through optimistic unchoking by other peers. His second claim is also true. He can run a client on each host, let each client “free-ride,” and combine the collected chunks from the different hosts into a single file. He can even write a small scheduling program to make the different hosts ask for different chunks of the file. This is actually a kind of Sybil attack in P2P networks. Problem 27 Peer 3 learns that peer 5 has just left the system, so Peer 3 asks its first successor (Peer 4) for the identifier of its immediate successor (peer 8). Peer 3 will then make peer 8 its second successor. Problem 28 Peer 6 would first send peer 15 a message, saying “what will be peer 6’s predecessor and successor?” This message gets forwarded through the DHT until it reaches peer 5, who realizes that it will be 6’s predecessor and that its current successor, peer 8, will become 6’s successor. Next, peer 5 sends this predecessor and successor information back to 6. Peer 6 can now join the DHT by making peer 8 its successor and by notifying peer 5 that it should change its immediate successor to 6. Problem 29 For each key, we first calculate the distances (using d(k,p)) between itself and all peers, and then store the key in the peer that is closest to the key (that is, with smallest distance value). Problem 30 Yes, randomly assigning keys to peers does not consider the underlying network at all, so it very likely causes mismatches. Such mismatches may degrade the search performance. For example, consider a logical path p1 (consisting of only two logical links): ABC, where A and B are neighboring peers, and B and C are neighboring peers. Suppose that there is another logical path p2 from A to C (consisting of 3 logical links): ADEC. It might be the case that A and B are very far away physically (and separated by many routers), and B and C are very far away physically (and separated by many routers). But it may be the case that A, D, E, and C are all very close physically (and all separated by few routers). In other words, a shorter logical path may correspond to a much longer physical path. Problem 31 If you run TCPClient first, then the client will attempt to make a TCP connection with a non-existent server process. A TCP connection will not be made. UDPClient doesn't establish a TCP connection with the server. Thus, everything should work fine if you first run UDPClient, then run UDPServer, and then type some input into the keyboard. If you use different port numbers, then the client will attempt to establish a TCP connection with the wrong process or a non-existent process. Errors will occur. Problem 32 In the original program, UDPClient does not specify a port number when it creates the socket. In this case, the code lets the underlying operating system choose a port number. With the additional line, when UDPClient is executed, a UDP socket is created with port number 5432 . UDPServer needs to know the client port number so that it can send packets back to the correct client socket. Glancing at UDPServer, we see that the client port number is not “hard-wired” into the server code; instead, UDPServer determines the client port number by unraveling the datagram it receives from the client. Thus UDP server will work with any client port number, including 5432. UDPServer therefore does not need to be modified. Before: Client socket = x (chosen by OS) Server socket = 9876 After: Client socket = 5432 Problem 33 Yes, you can configure many browsers to open multiple simultaneous connections to a Web site. The advantage is that you will you potentially download the file faster. The disadvantage is that you may be hogging the bandwidth, thereby significantly slowing down the downloads of other users who are sharing the same physical links. Problem 34 For an application such as remote login (telnet and ssh), a byte-stream oriented protocol is very natural since there is no notion of message boundaries in the application. When a user types a character, we simply drop the character into the TCP connection. In other applications, we may be sending a series of messages that have inherent boundaries between them. For example, when one SMTP mail server sends another SMTP mail server several email messages back to back. Since TCP does not have a mechanism to indicate the boundaries, the application must add the indications itself, so that receiving side of the application can distinguish one message from the next. If each message were instead put into a distinct UDP segment, the receiving end would be able to distinguish the various messages without any indications added by the sending side of the application. Problem 35 To create a web server, we need to run web server software on a host. Many vendors sell web server software. However, the most popular web server software today is Apache, which is open source and free. Over the years it has been highly optimized by the open-source community. Problem 36 The key is the infohash, the value is an IP address that currently has the file designated by the infohash.   Chapter 3 Review Questions Call this protocol Simple Transport Protocol (STP). At the sender side, STP accepts from the sending process a chunk of data not exceeding 1196 bytes, a destination host address, and a destination port number. STP adds a four-byte header to each chunk and puts the port number of the destination process in this header. STP then gives the destination host address and the resulting segment to the network layer. The network layer delivers the segment to STP at the destination host. STP then examines the port number in the segment, extracts the data from the segment, and passes the data to the process identified by the port number. The segment now has two header fields: a source port field and destination port field. At the sender side, STP accepts a chunk of data not exceeding 1192 bytes, a destination host address, a source port number, and a destination port number. STP creates a segment which contains the application data, source port number, and destination port number. It then gives the segment and the destination host address to the network layer. After receiving the segment, STP at the receiving host gives the application process the application data and the source port number. No, the transport layer does not have to do anything in the core; the transport layer “lives” in the end systems. For sending a letter, the family member is required to give the delegate the letter itself, the address of the destination house, and the name of the recipient. The delegate clearly writes the recipient’s name on the top of the letter. The delegate then puts the letter in an envelope and writes the address of the destination house on the envelope. The delegate then gives the letter to the planet’s mail service. At the receiving side, the delegate receives the letter from the mail service, takes the letter out of the envelope, and takes note of the recipient name written at the top of the letter. The delegate then gives the letter to the family member with this name. No, the mail service does not have to open the envelope; it only examines the address on the envelope. Source port number y and destination port number x. An application developer may not want its application to use TCP’s congestion control, which can throttle the application’s sending rate at times of congestion. Often, designers of IP telephony and IP videoconference applications choose to run their applications over UDP because they want to avoid TCP’s congestion control. Also, some applications do not need the reliable data transfer provided by TCP. Since most firewalls are configured to block UDP traffic, using TCP for video and voice traffic lets the traffic though the firewalls. Yes. The application developer can put reliable data transfer into the application layer protocol. This would require a significant amount of work and debugging, however. Yes, both segments will be directed to the same socket. For each received segment, at the socket interface, the operating system will provide the process with the IP addresses to determine the origins of the individual segments. For each persistent connection, the Web server creates a separate “connection socket”. Each connection socket is identified with a four-tuple: (source IP address, source port number, destination IP address, destination port number). When host C receives and IP datagram, it examines these four fields in the datagram/segment to determine to which socket it should pass the payload of the TCP segment. Thus, the requests from A and B pass through different sockets. The identifier for both of these sockets has 80 for the destination port; however, the identifiers for these sockets have different values for source IP addresses. Unlike UDP, when the transport layer passes a TCP segment’s payload to the application process, it does not specify the source IP address, as this is implicitly specified by the socket identifier. Sequence numbers are required for a receiver to find out whether an arriving packet contains new data or is a retransmission. To handle losses in the channel. If the ACK for a transmitted packet is not received within the duration of the timer for the packet, the packet (or its ACK or NACK) is assumed to have been lost. Hence, the packet is retransmitted. A timer would still be necessary in the protocol rdt 3.0. If the round trip time is known then the only advantage will be that, the sender knows for sure that either the packet or the ACK (or NACK) for the packet has been lost, as compared to the real scenario, where the ACK (or NACK) might still be on the way to the sender, after the timer expires. However, to detect the loss, for each packet, a timer of constant duration will still be necessary at the sender. The packet loss caused a time out after which all the five packets were retransmitted. Loss of an ACK didn’t trigger any retransmission as Go-Back-N uses cumulative acknowledgements. The sender was unable to send sixth packet as the send window size is fixed to 5. When the packet was lost, the received four packets were buffered the receiver. After the timeout, sender retransmitted the lost packet and receiver delivered the buffered packets to application in correct order. Duplicate ACK was sent by the receiver for the lost ACK. The sender was unable to send sixth packet as the send win
Changes in 2.4.6 (February 22, 2011): Brief summary : - Support more host OS to run on: - Include win64 native binary in the release. - Fixed failures on big endian hosts. - BIOS: Support for up to 2M ROM BIOS images. - GUI: select mouse capture toggle method in .bochsrc. - Ported most of Qemu's 'virtual VFAT' block driver (except runtime write support, but plus FAT32 suppport) - Added write protect option for floppy drives. - Bugfixes / improved internal debugger + instrumentation. Detailed change log : - CPU and internal debugger - Implemented Process Context ID (PCID) feature - Implemented FS/GS BASE access instructions support (according to document from http://software.intel.com/en-us/avx/) - Rewritten from scratch SMC detection algorithm - Implemented fine-grained SMC detection (on 128 byte granularity) - Bugfixes for CPU emulation correctness and stability - Fixed failures on Big Endian hosts ! - Print detailed page walk information and attributes in internal debugger 'page' command - Updated/Fixed instrumentation callbacks - Configure and compile - Bochs now can be compiled as native Windows x86-64 application (tested with Mingw gcc 4.5.1 and Microsoft Visual Studio Express 2010) - Added ability to configure CPUID stepping through .bochsrc. The default stepping value is 3. - Added ability to disable MONITOR/MWAIT support through .bochsrc CPUID option. The option is available only if compiled with --enable-monitor-mwait configure option. - Determine and select max physical address size automatically at configure time: - 32-bit physical address for 386/486 guests - 36-bit physical address for PSE-36 enabled Pentium guest - 40-bit physical address for PAE enabled P6 or later guests - Update config.guess/config.sub scripts to May 2010 revisions. - Update Visual Studio 2008 project files in build/win32/vs2008ex-workspace.zip - Added Bochs compilation timestamp after Bochs version string. - GUI and display libraries (Volker) - Added new .bochsrc option to select mouse capture toggle method. In addition to the default Bochs method using the CTRL key and the middle mouse button there are now the choices: - CTRL+F10 (like DOSBox) - CTRL+ALT (like QEMU) - F12 (replaces win32 'legacyF12' option) - display library 'x' now uses the desktop size for the maximum guest resolution - ROM BIOS - Support for up to 2M ROM BIOS images - I/O Devices - 3 new 'pseudo device' plugins created by plugin separation (see below) - Fixes for emulated DHCP in eth_vnet (patch from @SF tracker) - Added support for VGA graphics mode with 400 lines (partial fix for SF bug #2948724) - NE2K: Fixed "send buffer" command issue on big endian hosts - USB - converted common USB code plus devices to the new 'usb_common' plugin Now the USB device classes no longer exist twice if both HC plugins are loaded. - added 'pseudo device' in common USB code for the device creation. This makes the HCs independent from the device specific code. - USB MSD: added support for disk image modes (like ATA disks) - USB printer: output file creation failure now causes a disconnect - re-implemented "options" parameter for additional options of connected devices (currently only used to set the speed reported by device and to specify an alternative redolog file of USB MSD disk image modes) - hard drive - new disk image mode 'vvfat' - ported the read-only part of Qemu's 'virtual VFAT' block driver - additions: configurable disk geometry, FAT32 support, read MBR and/or boot sector from file, volatile write support using hdimage redolog_t class, optional commit support on Bochs exit, save/restore file attributes, 1.44 MB floppy support, set file modification date/time - converted the complete hdimage stuff to the new 'hdimage' plugin - new hdimage method get_capabilities() that can return special flags - vmware3, vmware4 and vvfat classes now return HDIMAGE_HAS_GEOMETRY flag - other disk image modes by default return HDIMAGE_AUTO_GEOMETRY if cylinder value is set to 0 - multiple sector read/write support for some image modes - new log prefix "IMG" for hdimage messages - floppy - added write protect option for floppy drives (based on @SF patch by Ben Lunt) - vvfat support - bugfix: close images on exit - SB16 - converted the sound output module stuff to the new 'soundmod' plugin - SF patches applied [3164945] hack to compile under WIN64 by Darek Mihocka and Stanislav [3164073] Fine grain SMC invalidation by Stanislav [1539417] write protect for floppy drives by Ben Lunt [2862322] fixes for emulated DHCP in eth_vnet - these S.F. bugs were closed/fixed [2588085] Mouse capture [3140332] typo in mf3/ps2 mapping of BX_KEY_CTRL_R [3111577] No "back" option in log settings [3108422] Timing window in NE2K emulation [3084390] Bochs won't load floppy plugin right on startup [3043174] Docbook use of '_' build failure [3085140] Ia_arpl_Ew_Rw definition of error [3078995] ROL/ROR/SHL/SHR modeling wrong when dest reg is 32 bit [2864794] BX_INSTR_OPCODE in "cpu_loop" causes crash in x86_64 host [2884071] [AIX host] prefetch: EIP [00010000] > CS.limit [0000ffff] [3053542] 64 bit mode: far-jmp instruction is error [3011112] error compile vs2008/2010 with X2APIC [3002017] compile error with vs 2010 [3009767] guest RFLAGS.IF blocks externel interrupt in VMX guest mode [2964655] VMX not enabled in MSR IA32_FEATURE_CONTROL [3005865] IDT show bug [3001637] CMOS MAP register meaning error [2994370] Cannot build with 3DNow support - these S.F. feature requests were closed/implemented [1510142] Native Windows XP x64 Edition binary [1062553] select mouse (de)activation in bochsrc [2930633] legacy mouse capture key : not specific enough [2930679] Let user change mouse capture control key [2803538] Show flags for pages when using "info tab" ------------------------------------------------------------------------- Changes in 2.4.5 (April 25, 2010): Brief summary : - Major configure/cpu rework allowing to enable/disable CPU options at runtime through .bochsrc (Stanislav) - Bugfixes for CPU emulation correctness and stability - Implemented X2APIC extensions (Stanislav) - Implemented Intel VMXx2 extensions (Stanislav) - Extended VMX capability MSRs, APIC Virtualization, X2APIC Virtualization, Extended Page Tables (EPT), VPID, Unrestricted Guests, new VMX controls. - Implemented PCLMULQDQ AES instruction - Extended Bochs internal debugger functionality - USB HP DeskJet 920C printer device emulation (Ben Lunt) Detailed change log : - Configure rework - Deprecate --enable-popcnt configure option. POPCNT instruction will be enabled automatically iff SSE4_2 is supported (like in hardware). - Make --ignore-bad-msrs runtime option in .bochsrc. Old --ignore-bad-msrs configure option is deprecated and should not be used anymore. - Enable changing part of CPU functionality at runtime through .bochsrc. - Now you could enable/disable any of SSEx/AES/MOVBE/SYSENTER_SYSEXIT/XSAVE instruction sets using new CPUID option in .bochsrc. - When x86-64 support is compiled in, you could enable/disable long mode 1G pages support without recompile using new CPUID option in .bochsrc. Configure options: --enable-mmx, --enable-sse, --enable-movbe, --enable-xsave, --enable-sep, --enable-aes, --enable-1g-pages are deprecated and should not be used anymore. - Local APIC configure option --enable-apic is deprecated and should not be used anymore. The LAPIC option now automatically determined from other configure options. XAPIC functionality could be enabled using new CPUID .bochsrc option. - Changed default CPU configuration (generated by configure script with default options) to BX_CPU_LEVEL=6 with SSE2 enabled. - CPU - Implemented PCLMULQDQ AES instruction - Implemented X2APIC extensions / enable extended topology CPUID leaf (0xb), in order to enable X2APIC configure with --enable-x2apic - Implemented Intel VMXx2 extensions: - Enabled extended VMX capability MSRs - Implemented VMX controls for loading/storing of MSR_PAT and MSR_EFER - Enabled/Implemented secondary proc-based vmexec controls: - Implemented APIC virtualization - Implemented Extended Page Tables (EPT) mode - Implemented Descriptor Table Access VMEXIT control - Implemented RDTSCP VMEXIT control - Implemented Virtualize X2APIC mode control - Implemented Virtual Process ID (VPID) - Implemented WBINVD VMEXIT control - Implemented Unrestricted Guest mode In order to enable emulation of VMXx2 extensions configure with --enable-vmx=2 option (x86-64 must be enabled) - Bugfixes for CPU emulation correctness - Fixed Bochs crash when accessing the first byte above emulated memory size - Internal Debugger - Introduced range read/write physical watchpoints - Allow reloading of segment registers from internal debugger - Improved verbose physical memory access tracing - BIOS - Fix MTRR configuration (prevented boot of modern Linux kernels) - Fix interrupt vectors for INT 60h-66h (reserved for user interrupt) by setting them to zero - Fix BIOS INT13 function 08 when the number of cylinders on the disk = 1 - I/O Devices - USB HP DeskJet 920C printer device emulation (Ben Lunt) - Misc - Updated Bochs TESTFORM to version 0.5 - SF patches applied [2864402] outstanding x2apic patches by Stanislav [2960379] Fix build with -Wformat -Werror=format-security by Per Oyvind Karlsen [2938273] allow instrumentation to change execute by Konrad Grochowski [2926072] Indirection operators in expressions by Derek Peschel [2914433] makesym.perl misses symbols by John R. Jackson [2908481] USB Printer by Ben Lunt - these S.F. bugs were closed/fixed [2861662] dbg_xlate_linear2phy needs to be updated [2956217] INT13 AH=8 returns wrong values when cylinders=1 [2981161] Allow DMA transfers to continue when CPU is in HALT state [2795115] NX fault could be missed [2964824] bad newline sequence in aspi-win32.h [913419] configure options and build process needs some work [2938398] gdbstub compile error with x86_64 enabled [2734455] shutdown/reset type 05 should reinit the PICs [1921294] extended memory less than 1M wrong size [1947249] BX_USE_EBDA_TABLES and MP table placement [1933859] BX_USE_EBDA_TABLES and memory overlapping [2923680] "help dregs" is a syntax error [2919661] CPU may fail to do 16bit near call [2790768] Memory corruption with SMP > 32, Panic BIOS Keyboard Error [2902118] interrupts vectors 0x60 to 67 should be NULL ! [2912502] Instruction Pointer behaving erratically [2901047] Bochs crashed, closed by guest os [2905385] Bochs crash [2901481] Instruction SYSRET and SS(PL) [2900632] Broken long mode RETF to outer priviledge with null SS [1429011] Use bx_phyaddr_t for physaddr vars and bx_adress for lin adr - these S.F. feature requests were closed/implemented [2955911] RPM preuninstall scriptlet removes /core [2947863] don't abort on unrecognised options [2878861] numerics in the disassembler output [2900619] make more CPU state changeable ------------------------------------------------------------------------- Changes in 2.4.2 (November 12, 2009): - CPU and internal debugger - VMX: Implemented TPR shadow VMEXIT - Bugfixes for CPU emulation correctness (mostly for VMX support). - Bugfixes and updates for Bochs internal debugger - On SMP system stepN command now affects only current processor - Memory - Bugfixes for > 32-bit physical address space. - Allow to emulate more physical memory than host actually could or would like to allocate. For more details look for new .bochsrc 'memory' option. - Cleanup configure options - All paging related options now will be automatically determined according to --enable-cpu-level option. Related configure options --enable-global-pages, --enable-large-pages, --enable-pae, --enable-mtrr are deprecated now. Only 1G paging option still remaining unchanged. - Deprecate --enable-daz configure option. Denormals-are-zeros MXCSR control will be enabled automatically iff SSE2 is supported (like in hardware). - Deprecate --enable-vme configure option, now it will be supported iff CPU_LEVEL >= 5 (like in hardware). - I/O Devices - Bugfixes for 8254 PIT, VGA, Cirrus-Logic SVGA, USB UCHI - SF patches applied [2817840] Make old_callback static by Mark Marshall [2874004] fix for VMWRITE instruction by Roberto Paleari [2873999] fix CS segment type during fast syscall invocation by Roberto Paleari [2864389] Debugger gui maximize on startup by Thomas Nilsen [2817868] Rework loops in the memory code by Mark Marshall [2812948] PIT bug by Derek - these S.F. bugs were closed/fixed [2833504] GUI debugger bug-about GDT display [2872244] BIOS writes not allowed value to MTRR MSR causing #GP [2885383] SDL GUI memory leak [2872290] compilation in AIX5.3 ML10 failes [2867904] crash with cirrus bx_vga_c::mem_write [2851495] BIOS PCI returns with INT flag = 0 [2860333] vista 64 guest STOP 109 (GDT modification) [2849745] disassembler bug for 3DNow and SSE opcodes [1066748] Wrong registers values after #RESET, #INIT [2836893] Regression: Windows XP installer unable to format harddrive [2812239] VMX: VM-Exit: Incorrect instruction length on software int [2814130] bx_debug lex/yacc files incorrectly generated [2813199] MP Tables Missing From BIOS [2824093] VMX exception bug [2811909] VMX : CS Access-rights Type.Accessed stays 0 [2810571] Compile Errors on OSX [2823749] GCC regression or VM_EXIT RDMSR/WRMSR bug [2815929] Vista/XP64 unnecessary panic [2803519] Wrong example in man page bochsrc - these S.F. feature requests were closed/implemented [422766] Large Memory configurations [1311287] Idea for a better GUI [455971] USB support [615363] debugger shortcut for repeat last cmd ------------------------------------------------------------------------- Changes in 2.4.1 (June 7, 2009): - Fixed bunch of CPUID issues - Bochs is now able to install and boot 64-bit Windows images! (special thanks to Mark Ebersole for his patch) - Several bugfixes in CPU emulation (mostly for x87 instructions) - Fixed two critical deadlock bugs in the Win32 gui (patches from @SF tracker) - Fixes related to the 'show ips' feature - removed conflicting win32-specific alarm() functions ('win32' and 'sdl' gui) - feature now works in wx on win32 - Added support for gdb stub on big endian machine (patch by Godmar Back) - Rewritten obsolete hash_map code in dbg symbols module (patch from @SF) - BIOS: implemented missing INT 15h/89h (patch by Sebastian Herbszt) ------------------------------------------------------------------------- Changes in 2.4 (May 3, 2009): Brief summary : - Added graphical Bochs debugger frontend for most of the supported platforms. - Thanks for Chourdakis Michael and Bruce Ewing. - Many new CPU features in emulation - Support for > 32 bit physical address space and configurable MSRs - VMX, 1G pages in long mode, MOVBE instruction - Bugfixes for CPU emulation correctness, debugger and CPU instrumentation. - New config interface 'win32config' with start and runtime menu - USB: added OHCI support, external hub and cdrom - Added user plugin interface support. Detailed change log : - CPU and internal debugger - Support for VMX hardware emulation in Bochs CPU, to enable configure with --enable-vmx option Nearly complete VMX implementation, with few exceptions: - Dual-monitor treatment of SMIs and SMM not implemented yet - NMI virtualization, APIC virtualization not implemented yet - VMENTER to not-active state not supported yet - No advanced features like Extended Page Tables or VPID - Support for configurable MSR registers emulation, to enable configure with --enable-configurable-msrs option Look for configuration example in .bochsrc and msrs.def - Support new Intel Atom(R) MOVBE instruction, to enable configure with --enable-movbe option - Support for 1G pages in long mode, to enable configure with --enable-1g-pages option - Support for > 32 bit physical address space in CPU. Up to 36 bit could be seen in legacy mode (PAE) and up to 40 bit in x86-64 mode. Still support the same amount of the physical memory in the memory object, so system with > 4Gb of RAM yet cannot be emulated. To enable configure with --enable-long-phy-address option. - Implemented modern BIOSes mode limiting max reported CPUID function to 3 using .bochsrc CPU option. The mode is required in order to correctly install and boot WinNT. - Added ability to configure CPUID vendor/brand strings through .bochsrc (patch from @SF by Doug Reed). - Many bugfixes for CPU emulation correctness (both x86 and x86-64). - Updated CPU instrumentation callbacks. - Fixed Bochs internal debugger breakpoints/watchpoints handling. - Configure and compile - Added ability to choose Bochs log file name and Bochs debugger log file name from Bochs command line (using new -log and -dbglog options) - Removed Peter Tattam's closed source external debugger interface from the code. - Removed --enable-guest2host-tlb configure option. The option is always enabled for any Bochs configuration. - Removed --enable-icache configure option. The option is always enabled for any Bochs configuration. Trace cache support still remains optional and could be configured off. - Added configure option to compile in GUI frontend for Bochs debugger, to enable configure with --enable-debugger-gui option. The GUI debugger frontend is enabled by default with Bochs debugger. - Removed --enable-port-e9-hack configure option. The feature now could be configured at runtime through .bochsrc. - Added configure option to enable/disable A20 pin support. Disabling the A20 pin support slightly speeds up the emulation. - reduced dependencies between source files for faster code generation - BIOS - Added S3 (suspend to RAM) ACPI state to BIOS (patch by Gleb Natapov) - Implemented MTRR support in the bios (patches by Avi Kivity and Alex Williamsion with additions by Sebastian Herbszt) - Bug fixes - I/O Devices - Added user plugin support - remaining devices converted to plugins: pit, ioapic, iodebug - added 'plugin_ctrl' bochsrc option to control the presence of optional device plugins without a separate option. By default all plugins are enabled. - added register mechanism for removable mouse and keyboard devices - Hard drive / cdrom - PACKET-DMA feature now supported by all ATAPI commands - ATAPI command 0x1A added (based on the Qemu implementation) - sb16 - Added ALSA sound support on Linux (PCM/MIDI output) - FM synthesizer now usable with MIDI output (simple piano only) - Fixed OPL frequency to MIDI note translation - Fixed MIDI output command - keyboard - added keyboard controller commands 0xCA and 0xCB - USB - USB code reorganized to support more HC types and devices - added USB OHCI support written by Ben Lunt - added external USB hub support (initial code ported from Qemu) - added USB cdrom support (SCSI layer ported from Qemu) - added status bar indicators to show data transfer - VGA - VBE video memory increased to 16 MB - implemented changeable VBE LFB base address (PCI only, requires latest BIOS and VGABIOS images) - I/O APIC - implemented I/O APIC device hardware reset - Config interface - new config interface 'win32config' with start and runtime menu is now the default on Windows ('textconfig' is still available) - win32 device config dialogs are now created dynamicly from a parameter list (works like the wx ParamDialog) - changes in textcofig and the wx ParamDialog for compatibility with the new win32 dialog behaviour - Bochs param tree index keys are case independent now - some other additions / bugfixes in the simulator interface code - Misc - updated LGPL'd VGABIOS to version 0.6c - Updated Bochs TESTFORM to version 0.4 - SF patches applied [2784858] IO Handler names are not compared properly [2712569] Legacy bios serial data buffer timeout bug by grybranix [2655090] 64 bit BSWAP with REX.W broken by M. Eby [2645919] CR8 bug when reading by M. Eby [1895665] kvm: bios: add support to memory above the pci hole by Izik Eidus [2403372] rombios: check for valid cdrom before using it by Sebastian [2307269] acpi: handle S3 by Sebastian [2354134] TAP networking on Solaris/Sparc repaired [2144692] The scsi device can not complete its writing data command by naiyue [1827082] [PATCH] Configurable CPU vendor by Marcel Sondaar [2217229] Panic on EBDA overflow in rombios32 by Sebastian [2210194] Log pci class code by Sebastian [1984662] red led for disk write and titlebar mod by ggbsf [2142955] Fix for monitor/mwait by Doug Gibson [2137774] Patch to fix bug: cdrom: read_block: lseek returned error by Gabor Olah [2134642] Fix scan_to_scanascii table for F11 and F12 by Ben Guthro & Steve Ofsthun [2123036] sdl fullscreen fix by ggbsf [2073039] Remove CMOS accsess from AML code by Gleb Natapov [2072168] smbios: add L1-L3 cache handle to processor information by Sebastian [2055416] bochsrc cpu options for cpuid vendor and brand string by Doug Reed [2035278] rombios: Fix return from BEV via retf by Sebastian [2035260] rombios: El Torito load segment fix by Sebastian [2031978] Fix VMware backdoor command 0Ah by Jamie Lokier [2015277] Remove obsolete comment about DATA_SEG_DEFS_HERE hack by Sebastian [2011268] Set new default format and unit only if both are supported by Sebastian [2001919] gdbstub: fix qSupported reply by Sebastian [2001912] gdbstub: enclose packet data by apostrophes by Sebastian [1998071] fix missing SIGHUP and SIGQUIT with term ui on mingw by Sebastian [1998063] fix wrong colors with term ui by Sebastian [1995064] Compile fix needed for --enable-debugger and gcc 4.3 by Hans de Goede [1994564] Fix typo in RDMSR BX_MSR_MTRRFIX16K_A0000 by Sebastian [1994396] Change hard_drive_post #if by Sebastian [1993235] TESTFORM email address update by Sebastian [1992322] PATCH: fix compilation of bochs 2.3.7 on bigendian machines by Hans de Goede [1991280] Shutdown status code 0Ch handler by Sebastian [1990108] Shutdown status code 0Bh handler by Sebastian [1988907] Shutdown status code 0Ah handler by Sebastian [1984467] two typos in a release! (2.3.7) [1981505] Init PIIX4 PCI to ISA bridge and IDE by Sebastian - these S.F. bugs were closed/fixed [2784148] an integer overflow BUG of Bochs-2.3.7 source code [2695273] MSVC cpu.dsp failure in 2.3.7.zip [616114] Snapshot/Copy crash on Win2K [2628318] 'VGABIOS-latest' bug [1945055] can't 'make install' lastest bochs on loepard [2031993] Mac OS X Makefile bug [1843199] install error on mac osx [2710931] Problem compiling both instrumentation and debugger [2617003] ExceptionInfo conflicts with OS X api [2609432] stepping causes segfault (CVS) [2605861] compile error with --enable-smp [1757068] current cvs(Jul19, 07) failed to boot smp [2426271] cannot get correct symbol entry [2471982] VGA character height glitches [1659659] wrong behaviour a20 at boot [1998027] minwg + --with-term + --with-out-win32 = link failure [1871936] bochs-2.3.6 make fails on wx.cc [1684666] info idt for long mode [2105989] could not read() hard drive image file at byte 269824 [1173093] Debugger totally not supports x86-64 [1803018] new win32debug dialog problems [2141679] windows vcc build broken [2162824] latest cvs fails to compile [2164506] latest bochs fails to start [2129223] MOV reg16, SS not working in real mode due to dead code [2106514] RIS / startrom.com install ALMOST works [2123358] SMP (HTT): wbinvd executed by CPU1 crashes CPU0 [2002758] Arch Linux: >>PANIC<< ATAPI command with zero byte count [2026501] El Torito incorrect boot segment:offset [2029758] BEV can return via retf instead of int 18h [2010173] x command breaks after one error about x/s or x/i [1830665] harddrv PANIC: ATAPI command with zero byte count [1985387] fail to make using gcc4 with --enable-debugger [1990187] testform feedback [1992138] Misspell in cpu/ia_opcodes.h - these S.F. feature requests were closed/implemented [2175153] Update MSVC project files [658800] front end program and bios [1883370] Make cd and floppy images more usable [422783] change floppy size without restarting [2552685] param tree names should be case insensitive [1214659] PC Speaker emu turnoff. Plugin Controll. [1977045] support 40 bit physical address [1506385] Intel Core Duo VT features [1429015] Support for user plugins [1488136] debugger access to floppy controller [1363136] Full debugger SMP and 64 bit support [2068304] Support for ACPI [431032] debugger "x" command [423420] profiling ideas (SMF) [445342] Add FM support? [928439] alsa ------------------------------------------------------------------------- Changes in 2.3.7 (June 3, 2008): Brief summary : + More optimizations in CPU code - Bochs 2.3.7 is more than 2x faster than Bochs 2.3.5 build ! - Implemented LBA48 support in BIOS - Added memory access tracing for Bochs internal debugger - Implemented Intel(R) XSAVE/XRSTOR and AES instruction set extensions - Many fixes in CPU emulation and internal debugger - MenuetOS64 floppy images booting perfect again ! - updated LGPL'd VGABIOS to version 0.6b Detailed change log : - CPU - Support of XSAVE/XRSTOR CPU extensions, to enable configure with --enable-xsave option - Support of AES CPU extensions, to enable configure with --enable-aes option - Fixed Bochs failure on RISC host machines with BxRepeatSpeedups optimization enabled - Implemented SYSENTER/SYSEXIT instructions in long mode - More than 100 bugfixes for CPU emulation correctness (both x86 and x86-64) - MenuetOS64 floppy images booting perfect again ! - Updated CPU instrumentation callbacks - Bochs Internal Debugger and Disassembler - Added memory access tracing for Bochs internal debugger, enable by typing 'trace-mem on' in debugger command line - Many bug fixes in Bochs internal debugger and disassembler - System BIOS (Volker) - Implemented LBA48 support - Added generation of SSDT ACPI table that contains definitions for available processors - Added RTC device to ACPI DSDT table - Added implementation of SMBIOS - I/O devices (Volker) - VGA - Implemented screen disable bit in sequencer register #1 - Implemented text mode cursor blinking - Serial - new serial modes 'pipe-server' and 'pipe-client' for win32 - new serial mode 'socket-server' - Configure and compile - Fixed configure bug with enabling of POPCNT instruction, POPCNT instruction should be enabled by default when SSE4.2 is enabled. - Removed --enable-magic-breakpoint configure option. The option is automatically enabled if Bochs internal debugger is compiled in. It is still possible to turn on/off the feature through .bochsrc. - Allow boot from network option in .bochsrc - Added Bochs version info for Win32 - Display libraries - implemented text mode character blinking in some guis - improved 'X' gui runtime dialogs - SF patches applied [1980833] Fix shutdown status code 5h handler by Kevin O'Connor [1928848] "pipe" mode for serial port (win32 only) by Eugene Toder [1956843] Set the compatible pci interrupt router back to PIIX by Sebastian [1956366] Do not announce C2 & C3 cpu power state support by Igor Lvovsky [1921733] support for LBA48 by Robert Millan [1938185] Fix link problem with --enable-debugger by Sebastian [1938182] Makefile.in - use @IODEV_LIB_VAR@ by Sebastian [1928945] fix for legacy rombios - e820 map and ACPI_DATA_SIZE by Sebastian [1925578] rombios32.c - fix ram_size in ram_probe for low memory setup by Sebastian [1908921] rombios32.c - move uuid_probe() call by Sebastian [1928902] improvements to load-symbols by Eugene Toder [1925568] PATCH: msvc compilation by Eugene Toder [1913150] rombios.c - e820 cover full size if memory <= 16 mb by Alexander van Heukelum [1919804] rombios.c - fix and add #ifdef comments by Sebastian [1909782] rombios.c - remove segment values from comment by Sebastian [1908918] SMBIOS - BIOS characteristics fix by Sebastian [1901027] BIOS boot menu support (take 3) [1902579] rombios32.c - define pci ids by Sebastian [1859447] Pass segment:offset to put_str and introduce %S by Sebastian [1889057] rombios.c - boot failure message by Sebastian [1891469] rombios.c - print BEV product string by Sebastian [1889851] Win32 version information FILEVERSION for bochs.exe by Sebastian [1889042] rombios.c - fix comment by Sebastian [1881500] bochsrc, allow boot: network by Sebastian [1880755] Win32 version information for bochs.exe by Sebastian [1880471] SMBIOS fix type 0 by Sebastian [1878558] SMBIOS fixes by Sebastian [1864692] SMBIOS support by Filip Navara [1865105] Move bios_table_area_end to 0xcc00 by Sebastian [1875414] Makefile.in - change make use by Sebastian [1874276] Added instrumentation for sysenter/sysexit by Lluis [1873221] TLB page flush: add logical address to instrumentation by Lluis [1830626] lba32 support by Samuel Thibault [1861839] Move option rom scan after floppy and hard drive post by Sebastian [1838283] Early vga bios init by Sebastian [1838272] rom_scan range parameter by Sebastian [1864680] Save CPUID signature by Filip Navara - these S.F. bugs were closed [1976171] Keyboard missing break code for enter (0x9C) [666433] physical read/write breakpoint sometimes fails [1744820] info gdt and info idt shows the entire tables [1755652] graphics: MenuetOS64 shows black screen [1782207] Windows Installer malfunction, Host=Linux, Guest=Win98SE [1697762] OS/2 Warp Install Failed [1952548] String to char * warnings [1940714] SYSENTER/SYSEXIT doesn't work in long mode [1422342] SYSRET errors [1923803] legacy rombios - e820 map and ACPI_DATA_SIZE [1936132] Link problem with --enable-debugger & --enable-disasm [1934477] Linear address wrap is not working [1424984] virtual machine freezes in Bochs 2.2.6 [1902928] with debugger cpu_loop leaves CPU with unstable state [1898929] Bochs VESA BIOS violates specs (banks == 1) [1569256] bug in datasegment change in long mode [1830662] ACPI: no DMI BIOS year, acpi=force is required [1868806] VGA blink enable & screen disable [1875721] Bit "Accessed" in LDT/GDT descriptors & #PF [1874124] bx_Instruction_c::ilen() const [1873488] bochs-2.3.6 make fails on dbg_main.cc - these S.F. feature requests were implemented [1422769] SYSENTER/SYSEXIT support in x86-64 mode [1847955] Version information for bochs(dbg).exe [939797] SMBIOS support ------------------------------------------------------------------------- Changes in 2.3.6 (December 24, 2007): Brief summary : + More than 25% emulation speedup vs Bochs 2.3.5 release! - Thanks to Darek Mihocka (http://www.emulators.com) for providing patches and ideas that made the speedup possible! + Up to 40% speedup vs Bochs 2.3.5 release with trace cache optimization! - Lots of bugfixes in CPU emulation - Bochs benchmarking support - Added emulation of Intel SSE4.2 instruction set Detailed change log : - CPU - Added emulation of SSE4.2 instruction set, to enable use --enable-sse=4 --enable-sse-extension configure options to enable POPCNT instruction only use configure option --enable-popcnt - Implemented MTRR emulation, to enable use --enable-mtrr configure option. MTRRs is enabled by default when cpu-level >= 6. - Implemented experimental MONITOR/MWAIT support including optimized MWAIT CPU state and hardware monitoring of physical address range, to enable use --enable-monitor-mwait configure option. - Removed hostasm optimizations, after Bochs rebenchmarking it was found that the feature bringing no speedup or even sometimes slows down emulation! - Merged trace cache optimization patch, the trace cache optimization is enabled by default when configure with --enable-all-optimizations option, to disable trace cache optimization configure with --disable-trace-cache - Many minor bugfixes in CPU emulation (both ia32 and x86-64) - Updated CPU instrumentation callbacks - Bochs Internal Debugger and Disassembler - Many fixes in Bochs internal debugger and disassembler, some debugger interfaces significantly changed due transition to the param tree architecture - Added support for restoring of the CPU state from external file directly from Bochs debugger - Configure and compile - Renamed configure option --enable-4meg-pages to --enable-large-pages. The option enables page size extensions (PSE) which refers to 2M pages as well. - Removed --enable-save-restore configure option, save/restore feature changed to be one of the basic Bochs features and compiled by default for all configurations. - Added new Bochs benchmark mode. To run Bochs in benchmark mode execute it with new command line option 'bochs -benchmark time'. The emulation will be automatically stopped after 'time' millions of emulation cycles executed. - Another very useful option for benchmarking of Bochs could be enabled using new 'print_timestamps' directive from .bochsrc: print_timestamps: enable=1 - Added --enable-show-ips option to all configuration scripts used to build release binaries, so all future releases will enjoy IPS display. - Enable alignment check in the CPU and #AC exception by default for --cpu-level >= 4 (like in real hardware) - SF patches applied [1491207] Trace Cache Speedup patch by Stanislav [1857149] Define some IPL values by Sebastian [1850183] Get memory access mode in BX_INSTR_LIN_READ by Lluis Vilanova [1841421] pic: keep slave_pic.INT and master_pic.IRQ_in bit 2 in sync by Russ Cox [1841420] give segment numbers in exception logs by Russ Cox [1801696] Allow Intel builds on Mac OS X [1830658] Fix >32GB disk banner by Samuel Thibault [1813314] Move #define IPL_* and typedef ipl_entry by Sebastian [1809001] Save PnP Option ROM Product Name string in IPL Boot Table by Sebastian [1821242] Fix for #1801285, Niclist.exe broken by Sebastian [1819567] Code warning cleanup [1816162] Update comment on bios_printf() by Sebastian [1811139] Trivial Fix when BX_PCIBIOS and BX_ROMBIOS32 not defined by Myles Watson [1811190] Improve HD recognition and CD boot by Myles Watson [1811860] Implement %X in bios_printf by Sebastian [1809649] printf %lx %ld %lu by Myles Watson [1809651] move BX_SUPPORT_FLOPPY by Myles Watson [1809652] dpte and Int13DPT fixes by Myles Watson [1809669] clip cylinders to 16383 in hard drive by Myles Watson [1799903] Build BIOS on amd64 by Robert Millan [1799877] Fix for parallel build (make -j2) by Robert Millan - these S.F. bugs were closed [1837354] website bug: View the Source link broken [1801268] Reset from real mode no longer working [1843250] Using forward slashes gives invalid filename [1823446] BIOS bug, local APIC #0 not detected [1801285] Niclist.exe broken [1364472] breakpoints sometimes don't work [994451] breakpoint bug [1801295] NSIS installer vs Windows Notepad [1715328] Unreal mode quirk [1503972] debugger doesn't debug first instruction on exception [1069071] div al, byte ptr [ds:0x7c18] fails to execute [1800080] Wrong "BX_MAX_SMP_THREADS_SUPPORTED" assertion - these S.F. feature requests were implemented [1662687] Download for Win32-exe with x64 Mode and debugging [604221] Debugger command: query lin->phys mapping ------------------------------------------------------------------------- Changes in 2.3.5 (September 16, 2007): Brief summary : - Critical problems fixed for x86-64 support in CPU and Bochs internal debugger - ACPI support - The release compiled with x86-64 and ACPI - Hard disk emulation supports ATA-6 (LBA48 addressing, UDMA modes) - Added emulation of Intel SSE4.1 instruction set Detailed change log : - CPU - Fixed critical bug with 0x90 opcode (NOP) handling in x86-64 mode - implied stack references where the stack address is not in canonical form should causes a stack exception (#SS) - Added emulation of SSE4.1 instruction set (Stanislav) - Do not save and restore XMM8-XMM15 registers when not in x86-64 mode - Fixed zero upper 32-bit part of GPR in x86-64 mode - CMOV_GdEd should zero upper 32-bit part of GPR register even if the 'cmov' condition was false ! - Implemented CLFLUSH instruction, report non-zero cache size in CPUID - Fixed PUSHA/POPA instructions behavior in real mode - Fixed detection of inexact result by FPU - Fixed denormals-are-zero (DAZ) handling by SSE convert instructions - Implemented Misaligned Exception Mask support for SSE (MXCSR[17]) - Implemented Alignment Check in the CPU and #AC exception, to enable use --enable-alignment-check configure option - General - 2nd simulation support in wxBochs now almost usable (simulation cleanup code added and memory leaks fixed) - Configure and compile - several fixes for MacOSX, OpenBSD and Solaris 10 - enable save/restore feature by default for all configurations - reorganized SSE configure options to match Intel(R) Programming Reference Manual, new option introduced for SSE extensions enabling. To enable Intel Core Duo 2 new instructions use --enable-sse=3 --enable-sse-extension enabling of SSE4.1 (--enable-sse=4) will enable SSE3 extensions as well - removed old PIT, always use new PIT written by Greg Alexander, removed configure option --enable-new-pit - I/O devices (Volker) - Floppy - partial non-DMA mode support (patch by John Comeau) - Hard drive / cdrom - hard disk emulation now supports ATA-6 (LBA48 addressing, UDMA modes) - VMWare version 4 disk image support added (patch by Sharvil Nanavati) - PCI - initial support for the PIIX4 ACPI controller - Serial - added support for 3-button mouse with Mousesystems protocol - USB - experimental USB device change support added - rewrite of the existing USB devices code - new USB devices 'disk' and 'tablet' (ported from the Qemu project) - Bochs internal debugger - fixed broken debugger "rc file" option (execute debugger command from file) - implementation of a gui frontend ("windebug") for win32 started - gdbstub now accepts connection from any host - several documentation updates - a lot of disasm and internal debugger x86_64 support fixes - Configuration interface - fixes and improvements to the save state dialog handling - Display libraries - text mode color handling improved in some guis - win32 fullscreen mode (patch by John Comeau) - System BIOS (Volker) - 32-bit PM BIOS init code for ACPI, PCI, SMP and SMM (initial patches by Fabrice Bellard) - PCI BIOS function "find class code" implemented - SF patches applied [1791000] 15h 8600h is reading the wrong stack frame by Sebastian [1791016] rombios32.c, ram_probe(), BX_INFO missing value by Sebastian [1786429] typo in bochsrc.5 by Sebastian [1785204] Extend acpi_build_table_header to accept a revision number by Sebastian [1766536] Partial Patch for Bug Report 1549873 by Ben Lunt [1763578] ACPI Table Revision 0 -> 1 [1642490] implement alignment check and #AC exception by Stanislav Shwartsman [1695652] [PATCH] .pcap pktlog and vnet PXE boot by Duane Voth [1741153] Add expansion-ROM boot support to the ROMBIOS [1734159] Implemented INT15h, fn 0xC2 (mouse), subfn 3, set resolution [1712970] bios_printf %s fix [1573297] PUSHA/POPA real mode fix by Stanislav Shwartsman [1641816] partial support for non-DMA access to floppy by John Comeau [1624032] shows where write outside of memory occurred by John Comeau [1607793] allow fullscreen when app requests it by John Comeau [1603013] Bugfix for major NOP problem on x64 by mvysin [1600178] Make tap and tuntap compile on OpenBSD by Jonathan Gray [1149659] improve gdbstub network efficiency by Avi Kivity [1554502] Trivial FPU exception handling fix - these S.F. bugs were closed [1316008] Double faults when it shouldn't - gcc 4.0.2 [1787289] broken ABI for redolog class when enable-compressed-hd [1787500] tftp_send_optack not 64bit clean [1264540] Security issue with Bochs website [1767217] Debugger Faults including ud2 [1729822] Various security issues in io device emulation [1675202] mptable hosed (bad entry count in header) [1197141] 'make install' installs to bad location [1157623] x86Solaris10 cannot recoginize ACPI RSD PTR [1768254] large HDD in Bochs/bximage [1496157] Windows Vista Beta2 dosn't boot [1755915] Illegal Hard Disk Signature Output [1717790] info gdt and info idt scrolls away, too long result [1726640] Debugger displays incorrect segment for mov instruction [1719156] Typo in misc_mem.cpp [1715270] Debugger broken in/beyond 2.3 [1689107] v8086 mode priviledge check failed [1704484] A few checks when CPU_LEVEL < 4 [1678395] Problem with zero sector... [876990] SA-RTL OS fails on PIC configuration [1673582] save/restore didn't restore simulation correctly [1586662] EDD int 13h bug, modify eax [666618] POP_A Panic in DOS EMU [1001485] panic: not enough bytes on stack [1667336] delay times an order of magnitude slow [1665601] crash disassembling bootcode [1657065] CVS sources won't compile [1653805] bochs's gdbstub uses incorrect protocol [1640737] ASM sti command frezzes guest OS [1636439] latest CVS sources don't compile under Cygwin [1634357] disasm incorrect (no sign ext) displacement in 64-bit mode [1376453] pcidev segfaults bochs [1180890] IOAPIC in BOCHS - WinXP 64 in MP version [1597528] 2.3 fails to compile on amd64 [1526255] FLD1 broken when compaling with gcc 4.0.x [1597451] eth_fbsd is broken under FreeBSD [1571949] Bochs will not compile under Solaris [1500216] Bochs fails to boot BeOs CD [1458339] bochs-2.2.6 WinXP Binary ACPI error installing FreeBSD 6.0 [1440011] patches needed for FreeBSD 6.0 to compile Bochs [431674] some devices don't have a prefix [458150] QNX demo disk crashes with new pit [818322] Bochs 2.1 cvs: OS/2 - read verify on non disk [906840] KBD: bogus scan codes generated in set 3 [1005053] No keyboard codes translation [1109374] Problem with Scancodeset 2 [1572345] Bochs won't continue [1568153] Bochs looks for (and loads?) unspecified display libraries [1563462] Errors in /iodev/harddrv.h [1562172] TLB_init() fails to initialize priv_check array if USE_TLB 0 [1385303] debugger crashes after panic [1438227] crc.cpp missing in bx_debug version 2.2.6 [1501825] debugger crashes on to high input [1420959] Memory leak + buffer overflow in Bochs debugger [1553289] Error in Dis-assembler [542464] I cannot use FLAT [1548270] Bochs won't die with its pseudo terminal [1545588] roundAndPackFloatx80 does not detect round up correctly ------------------------------------------------------------------------- Changes in 2.3 (August 27, 2006): Brief summary : - limited save/restore support added (config + log options, hardware state) - configuration parameter handling rewritten to a parameter tree - lots of cpu and internal debugger fixes - hard disk geometry autodetection now supported by most of the image types - hard disk emulation now supports ATA-3 (multiple sector transfers) - VBE memory size increased to 8MB and several VGA/VBE fixes - updated LGPL'd VGABIOS to version 0.6a Detailed change log : - CPU and internal debugger fixes - Fixed bug in FSTENV instruction (Stanislav Shwartsman) - Recognize #XF exception (19) when SSE is enabled - Fixed bug in PSRAW/PSRAD MMX and SSE instructions - Save and restore RIP/RSP only for FAULT-type exceptions, not for traps - Correctly decode, disassemble and execute multi-byte NOP '0F F1' opcode - Raise A20 line after system reset (Stanislav Shwartsman) - Implemented SMI and NMI delivery (APIC) and handling in CPU (Stanislav) - Experimental implementation of System Management Mode (Stanislav) - Added emulation of SSE3E instructions (Stanislav Shwarstman) - Save and restore FPU opcode, FIP and FDP in FXSAVE/FRSTOR instructions - Fixed bug in MOVD_EdVd opcode (always generated #UD exception) - Fixed critical issue, Bochs was not supporting > 16 bit LDT.LIMIT values - Many fixes in Bochs internal debugger and disassembler - CPU x86-64 fixes - Fixed SYSRET instruction implementation - Fixed bug in CALL/JMP far through 64-bit callgate in x86-64 mode - Correctly decode, disassemble and execute 'XCHG R8, rAX' instruction - Correctly decode and execute 'BSWAP R8-R15' instructions - Fixed ENTER and LEAVE instructions in x86-64 mode (Stanislav) - Fixed CR4 exception condition (No Name) - Fixed x86 debugger to support x86-64 mode (Stanislav) - APIC and SMP - Support for Dual Core and Intel(R) HyperThreading Technology. Now you could choose amount of cores per processor and amount of HT threads per core from .bochsrc for SMP simulation (Stanislav Shwartsman) - Allow to control SMP quantum value through .bochsrc CPU option parameter. Previous Bochs versions used hardcoded quantum=5 value. - Fixed interrupt priority bug in service_local_apic() - Fixed again reading of APIC IRR/ISR/TMR registers. Finally it becomes fully correct :-) - Configure and compile - Moved configure time --enable-reset-on-triple-fault option to runtime, the 'cpu' option in .bochsrc is extended and the old configure option is deprecated (Stanislav Shwartsman) - Removed --enable-pni configure option, to compile with PNI use --enable-sse=3 instead (Stanislav Shwartsman) - enable SEP (SYSENTER/SYSEXIT) support by default for Penitum II+ processor emulation (i.e. if cpu-level >= 6 and MMX is enabled) - general - Limited save/restore support added. The state of CPU, memory and all devices can be saved now (state of harddisk images not handled yet). - Fixed several memory leaks - configuration interface - Configuration parameter handling rewritten to a parameter tree. This is required for dynamic menus/dialogs, user-defined options and save/restore. - Support for user-defined bochsrc options added - help support at the parameter prompt in textconfig added - I/O devices (Volker) - Floppy - partial sector transfers fixed - Hard drive / cdrom - several fixes to the IDE register behaviour (e.g. in case of a channel with only one drive connected) - fixed data alignment of 'growing' hard drive images (sharing images between Windows and Linux now possible) - disk geometry autodetection now supported by most of the image types (unsupported: external, dll and compressed modes) - multi sector read/write commands implemented - hard disk now reporting ATA-3 supported - ATAPI 'inquiry' now returns a unique device name - Keyboard - reset sent to keyboard has no effect on the 8042 (scancode translation) - PCI - forward PIRQ register changes to the I/O APIC (if present) - attempt to fix and update the emulation part of 'pcidev' (untested) - VGA - VBE memory size increased to 8MB and several VBE fixes - VGA memory read access fixed (bit plane access and read mode) - VGA memory is now a part of the common video memory - System BIOS (Volker) - enable interrupts before executing INT 19h - fixed ATA device detection in case of one drive only connected to controller - improved INT 15h function AX=E820h - real mode PCI BIOS now returns IRQ routing information (function 0Eh) - keyboard LED flags handling fixed and improved - fixed handling of extended keys in INT 09h - Updated LGPL'd VGABIOS to version 0.6a - SF patches applied [1340111] fixes and updates to usb support by Ben Lunt [1539420] minor addition to pci_usb code by Ben Lunt [1455958] call/jmp through call gate in 64-bit mode [1433107] PATCH: fix compile with wxwindows 2.6 (unicode / utf8) by jwrdegoede [1386671] Combined dual core and hyper-threading patch - these S.F. bugs were closed [833927] TTD: System Error TNT.40025: Unexpected processor exception [789230] Sending code that shows lock up when setting idt [909670] Problems with Symantec Ghost [1540241] include missing in osdep.cc [1539373] Incorrect disasm for "mov moffset,bla" in 64bit [1538419] incorrect disassembly of [rip+disp] with rex.b [1535432] shift+cursor key maps to a digit [1504891] Knoopix 5.0.1 error [1424355] bochs-2.2.6 ata failure in windoze 98se [1533979] wrong disassembly of IN instruction [620059] paste won't stop [1164904] status bar doesn't show num/caps/scroll lock status [1061720] ATA Support level for HD [1522196] Broken CHANGES link in main page [1438415] crash if screen scrolled downwards [778441] Shouldn't interrupts be enable after BIOS? [1514949] I got a problem with the 8253 timer [1513544] disasm of 0xec (in AL,DX) returns ilen of 2 instead of 1 [1508947] APIC interrupt priority checking and interrupt delivery [766286] Debugger halts after any GPF exception [639143] va_list is not a pointer on linuxppc [1501815] debugger examines memory over page-boundary wrong [1503978] movsb/w/d doesn't work when direction is stored [1499405] WinPCap has changed URL hosting [1498519] APIC IRR bits not set while interrupts disabled [1498193] Bochs segfaults on LTR instruction [787140] Guest2HostTLB optimization bug [1492070] instrument stop [1487772] No SEP on P4 [1488335] Growing hard disk images severe interoperability errors! [1076312] Shadow RAM and TLB [1282249] The real i440FX chipset Award bios hangs [1479763] mistake "mov ax,[es:di]" for "mov ax,[ds:di]" [1453575] Misconfigured floppy DMA transfers do not terminate. [1460068] Incorrect handling for the Options Menu Item [910203] bochs-2.1.1 wx.lo failed [1438654] PANIC when trying to run install-amd64-minimal-2005.0.iso [1458320] compile hdimage.h fails [1455880] bochs-2.2.6,2: make error on FreeBSD [696890] Network wouldn't run under W2k hosting MSDOS [673391] SMP timer problems [1291059] wxWindows GUI on non-windows/configure issue [1356450] bochs 2.2.1 errors-omittions [1178017] Win98 guest cannot receive network packets from host [1076315] a20_mask after restarting [1436323] real hw does not panic when bad Ib in CMPSS_VssWssIb [1435269] cdrom_amigaos is not compilable [1433314] disasm issues [1170614] relative jumps/calls wrong in debugger [758121] user might get confused when interrupt handler invoked [1170622] You cannot toggle OFF "show" flags [1406387] JMP instruction should display absolute address [1428813] PANIC: ROM address space out of range [1426288] DR-DOSs EMM386 problem [1412036] Bochs cannot recognize PCI NIC correctly [435115] dbg: modebp broken and no docs [1419366] disasm cs:eip does not work anymore [1419393] SSE's #XF exception -> "exception(19): bad vector" [1419429] disassembly of "260f6f00" show DS: instead of ES: prefix [1417583] Interrupt behaviour changed from 2.2.1 to 2.2.5 [1418281] 'push' (6A) incorrectly disassembled [1417791] FLDENV generating exception when real hw does not. [1264583] OS/2 1.1 doesn't run ------------------------------------------------------------------------- Changes in 2.2.6 (January 29, 2006): - First major SMP release ! - several APIC and I/O APIC fixes make SMP Bochs booting Windows NT4.0 or Knoppix 4.0.2 without noapic kernel option in SMP configuration. - critical APIC timer bug fixed - obsolete SMP BIOS images removed (MP tables created dynamicaly) - determine number of processors in SMP configuration through .bochsrc new .bochsrc option 'CPU' allows to choose number of processors to emulate - new configure option --enable-smp to configure Bochs for SMP support, the old --enable-processors=N option is deprecated - CPU and internal debugger fixes - enabled #PCE bit in CR4 register, previosly setting of this bit generated #GP(0) fault - enabled LAHF/SAHF instructions in x86-64 mode - fixed bug in PMULUDQ SSE2 instruction - fixes in Bochs debugger - Configure and compile - enable VME (virtual 8086 mode extensions) by default if cpu-level >= 5 - enable Bochs disassembler by default for all configurations - win32 installer script improvements - ips parameter moved to new 'CPU' option - show IPS value in status bar if BX_SHOW_IPS is enabled - Other - several fixes in the hard drive, keyboard, timer, usb and vga code - new user button shortcut "bksl" (backslash) - updated Bochs instrumentation examples - user and development documentation improved ------------------------------------------------------------------------- Changes in 2.2.5 (December 30, 2005): Brief summary : - added virtual 8086 mode extensions (VME) implementation - several fixes/improvements in x86-64 emulation, debugger and disassembler - new serial mode 'socket' connects a network socket - IDE busmaster DMA feature for harddisks and cdroms completed and enabled - many improvements in Bochs emulated I/O devices (e.g. floppy, cdrom) - Updated LGPL'd VGABIOS to version 0.5d Detailed change log : - CPU - fixed XMM registers restore in FXRSTOR instruction (Andrej Palkovsky) - print registers dump to the log if tripple fault occured - fixed PANIC in LTR instruction (Stanislav) - added virtual 8086 mode extensions (VME) implementation, to enable configure with --enable-vme (Stanislav) - flush caches and TLBs when executing WBINVD and INVD instructions - do not modify segment limit and AR bytes when modifying segment register in real mode (support for unreal mode) - fixed init/reset values for LDTR and TR registers - reimplemented hardware task switching mechanism (Stanislav) - generate #GP(0) when fetching instruction cross segment boundary - CPU (x86-64) (Stanislav Shwartsman) - implemented call_far/ret_far/jmp_far instructions in long mode - fixed IRET operation in long mode - fixed bug prevented setting of NXE/FFXSR bits in MSR.EFER register - implemented RDTSCP instruction - do not check CS.limit when prefetching instructions in long mode - fixed masked write instructions (MASKMOVQ/MASKMOVDQU) in long mode - fetchdecode fixes for x86-64 - APIC - Fixed bug in changing local APIC id (Stanislav) - Fixed reading of IRR/ISR/TMR registers (patch by wmrieker) - Implemented spurious interrupt register (Stanislav, patch by wmrieker) - Fixed interrupt delivery bug (anonymous #SF patch) - Correctly implemented ESR APIC register (Stanislav) - Bochs debugger - Fixed bug in bochs debugger caused breakpoints doesn't fire sometimes (Alexander Krisak) - watchpoints in device memory fixed (Nickolai Zeldovich) - new debug interface to access Bochs CPU general purpose registers with support for x86-64 - Disassembler (Stanislav Shwartsman) - Fixed disassembly for FCOMI/FUCOMI instructions - Full x86-64 support in disassembler. The disassembler module extended to support x86-64 extensions. Still limited by Bochs debugger which is not supporting x86-64 at all ;( - I/O devices (Volker) - general - memory management prepared for large BIOS images (up to 512k) - slowdown timer sleep rate fixed (now using 1 msec on all platforms) - some device specific parameter handlers moved into the device code - serial - new serial mode 'socket' connects a network socket (#SF patch by Andrew Backer) - hard drive / cdrom - assign a unique serial number to each drive (fixes harddrive detection problems with Linux kernels 2.6.x: "ignoring undecoded slave") - geometry autodetection for 'flat' hard disk images added. Works with images created with bximage (heads = 16, sectors per track = 63) - ATAPI command 'read cd' implemented, some other commands improved - cdrom read block function now tries up to 3 times before giving up - emulation of raw cdrom reads added, some other lowlevel cdrom fixes - IDE busmaster DMA feature for harddisks and cdroms completed and enabled - disk image size limit changed from 32 to 127 GB - split ATA/ATAPI emulation code and image handling code - floppy - fixes for OS/2 (patch by Robin Kay) - disk change line behaviour fixed (initial patch by Ben Lunt) - end-of-track (EOT) condition handling implemented - more accurate timing for read/write data and format track commands using a motor speed of 300 RPM - timing of recalibrate and seek commands now depends on the step rate, date rate and the steps to do - floppy controller type changed to 82077AA - cmos - RTC 12-hour and binary mode implemented - number of CMOS registers changed from 64 to 128 - bochsrc option 'cmosimage' improved - save cmos image on exit if enabled - speaker - simple speaker support for OS X added (patch by brianonn@telus.net) - pci - BeOS boot failure fix in the PCI IDE code - don't register i/o and memory regions during PCI probe - vga - memory allocation for vga extensions fixed - usb - some bugfixes by Ben Lunt (mouse and keypad are usable now) - networking modules - VDE networking module now enabled on Linux - display libraries - general - new syntax for the userbutton shortcut string and more keys supported - win32 - fixed keycode generation for right alt/ctrl/shift keys - runtime dialog is now a property sheet - x11 - simple dialog boxes for the "ask" and "user shortcut" feature implemented - Slovenian keymap added (contributed by Mitja Ursic) - configuration interface - ask dialog is now enabled by default for win32, wx and x display libraries - bochsrc option floppy_command_delay is obsolete now (floppy timing now based on hardware specs) - floppy image size detection now available in the whole config interface - some device specific parameter handlers moved into the device code - calculate BIOS ROM start address from image if not specified - System BIOS (Volker) - PCI i/o and memory base address initialization added - several keyboard interrupt handler fixes (e.g. patch by japheth) - several floppy fixes (e.g. OS/2 works with patch by Robin Kay) - some more APM functions added - Updated LGPL'd VGABIOS to version 0.5d - generate SMP specific tables dynamicly by the Bochs memory init code - SF patches applied [1389776] Disk sizes over 64 Gbytes by Andrzej Zaborowski [1359162] disasm support for x86-64 by Stanislav Shwartsman [857235] task priority and other APIC bugs, etc by wmrieker [1359011] build breaks for 386 + debugger + disasm by shirokuma [1352761] Infinite loop when trying to debug a triple exception [1311170] small APIC bug fix (interrupt sent to the wrong CPU) [1309763] Watchpoints don't work in device memory by Nickolai Zeldovich [1294930] change line status on floppy by Ben Lunt [1282033] SSE FXRESTORE not working correctly by Ondrej Palkovsky [816979] wget generalizations by Lyndon Nerenberg [1214886] No more pageWriteStamp / unified icache by H. Johansson [1107945] com->socket redirection support by Andrew Backer - these S.F. bugs were closed [669180] win95 install : unknown SET FEATURES subcommand 0x03 [1346692] bochs 2.2.1 VGA BIOS error [1354963] floppy in KolibriOS [1378204] error: bochs-2.2.1, --enable-sb16, --disable-gameport [1368412] VDE problems in BOCHS [533446] CPU and APIC devices appear twice [1000796] bximage fails to create image of specified size [1170793] Quarterdeck QEMM doesn't work [923704] Multiple opcode prefixes don't reflect Trap 13 [1166392] DocBook/documentation issues [1368239] broken grater than 4GB size of sparse type hd image [1365830] i386 compile breaks on paging [427550] Incomplete IRETD implementation [1215081] MSVC workspace STILL not fixed [736279] Jump to Task [1356488] FD change fail & occur error [957615] [CPU ] prefetch: RIP > CS.limit [1353866] not booting linux-2.6.14 [1351667] load32bitOSImage does not work with --enable-x86-debugger [1217476] Incorrect (?) handling of segment registers in real mode [1184711] OS2 DOS crash [2.2.pre2] [624330] support for disks > 32GiB [1348368] bochs 2.2.1 bximage error [1342081] Configuration Menu option failed [1138616] OS/2 Warp 4 hangs when booting [1049840] mouse and video conflict [1164570] Unable to perform Fedora Core 4 test 1 installation [1183201] Windows 2000 (MSDN build 2150?) does not completely install [1194284] Can't boot from CD-ROM (Windows NT) [962969] Windows NT crashes while trying to intall them. [1054594] WinXP install halts (redo) [1153107] Windows XP fails with BSOD on 'vga' [938518] Win XP installation fails [645420] getHostMemAddr vetoed direct read [1179985] MS XENIX: >>PANIC<< VGABIOS panic at vgabios.c, line 0 [1329600] WBINVD and INVD should flush caches and TLB [638924] eliminate BX_USE_CONFIG_INTERFACE [1048711] Funny behaviour with CTRL [1288450] keyboard BIOS error [1310706] Keyboard - about key SHIFT [1295981] Ubuntu 5.04 Live-CD won't boot in Bochs [879047] APIC timer behavior different before reset and after [1188506] I still can't install the german Windows XP! [1301847] Windows XP dosn't boot - FXRSTOR problem ? [661259] does not boot QNX under WinX [924412] Keyboard lock states all whacked [681127] MIPSpro compiler (IRIX) is allergic to ^M [1285923] BIOS keyboard handler [516639] ATA controller revisited... [657918] does not boot BeOS under WinX [649245] BeOS CD locks halfway on boot [1094385] Attachment for bug 1090339 (beos failure) [1183196] BeOS 4.5 developer CD does not install [1090339] BeOS fails to boot [639484] panics when int 13 is called [711701] divide by zero [704295] ATAPI/BIOS call missing [682856] hard drive problems [627691] Cursor keys problem [588011] keyboard not working [542260] os/2 warp crashes with floppy handling [1273878] SB16 doesn't work in pure DOS [542254] OS/2 FDC driver dies [1099610] Windows 98 SE Does not install [875479] cr3 problem on task switch [731423] NE2000 causing PANIC on Win2K detection [1156155] bochs fails to boot plan9 iso [1251979] --enable-cpu-level=3 should assume --without-fpu [1257538] Interupt 15h 83h - set wait event interval [658396] Panic for DR DOS emm386 [679339] /? doesn't divulge Bochs command-line syntax [1167016] call/jump/return_protected doesn't support x86-64 [1252432] Mac OS X compile bug [881442] Bochs 2.1 PANIC when loading DOS Turbo Pascal protected mode [1249324] Boch2.2.1 Buffer Overfollow in void bx_local_apic_c::init () [1197144] 'make install' has dependency on wget [1079595] LTR:386TSS: loading tr.limit < 103 [1244070] Compilation Error in gui/rfb.cc [761707] CPU error when trying to start Privateer [517281] Crash running Privateer in DOS... ------------------------------------------------------------------------- Changes in 2.2.1 (July 8, 2005): - Fixed several compilation warnings and errors for different platforms (Volker) - Fixed FPU tag word restore in FXRSTOR instruction (Stanislav) - Added missing scancodes for F11 and F12 to BIOS translation table (Volker) - Bochs disassembler bugfixes (h.johansson) - About 5% emulation speed improvement (h.johansson) - Handle writing of zero to APIC timer initial count register (Stanislav) - Enable Idle-Hack for 'TERM' GUI (h.johansson) - Reduced overhead of BX_SHOW_IPS option to minimum. Now every simulation could run with --enable-show-ips without significant performance penalty. (Stanislav) - Fixed pcipnic register access (Volker) - Limited write support for TFTP server in 'vnet' networking module added (Volker) - Changed some timing defaults to more useful values (Volker) - WinXP/2003 style common controls now supported (Vitaly Vorobyov) - Updated LGPL'd VGABIOS to version 0.5c (Volker) - Added new BX_INSTR_HLT callback to instrumentation (Stanislav) ------------------------------------------------------------------------- Changes in 2.2 (May 28, 2005): Brief summary : - New floating point emulator based on SoftFloat floating point emulation library. - improved x86-64 emulation - Cirrus SVGA card emulation added - status bar with indicators for keyboard, floppy, cdrom and disk (gui dependant) - many improvements in Bochs emulated I/O devices (e.g. PCI subsystem) Detailed change log : - CPU - fixes for booting OS/2 by Dmitri Froloff - fixed v8086 priveleged instruction processing bug (was also reported by LightCone Aug 7 2003) - exception process bug (was reported by Diego Henriquez Sat Nov 15 01:16:51 CET 2003) - segment validation with IRET instruction - CS segment not present exception processing with IRET - several fixes by Kevin Lawton - add MSVC host asm instructions (patch by suzu) - fixed bug in HADDPD/HSUBP
集合了 所有的 Unix命令大全 登陆服务器时输入 公帐号 openlab-open123 telnet 192.168.0.23 自己帐号 sd08077-you0 ftp工具 192.168.0.202 tools-toolss 老师测评网址 http://172.16.0.198:8080/poll/ 各个 shell 可互相切换 ksh:$ sh:$ csh:guangzhou% bash:bash-3.00$ 一、注意事项 命令和参数之间必需用空格隔开,参数和参数之间也必需用空格隔开。 一行不能超过256个字符;大小写有区分。 二、特殊字符含义 文件名以“.”开头的都是隐藏文件/目录,只需在文件/目录名前加“.”就可隐藏它。 ~/ 表示主目录。 ./ 当前目录(一个点)。 ../ 上一级目录(两个点)。 ; 多个命令一起用。 > >> 输出重定向 。将一个命令的输出内容写入到一个文件里面。如果该文件存在, 就将该文件的内容覆盖; 如果不存在就先创建该文件, 然后再写入内容。 输出重定向,意思就是,将原来屏幕输出变为文件输出,即将内容输到文件。 < << 输入重定向。 本来命令是通过键盘得到输入的,但是用小于号,就能够使命令从文件得到输入。 \ 表示未写完,回车换行再继续。 * 匹配零个或者多个字符。 ? 匹配一个字符。 [] 匹配括号里的内容[a-z][A-Z][0-9]。 ! 事件。 $ 取环境变量的值。 | 管道。把前一命令的输出作为后一命令的输入,把几个命令连接起来。 |经常跟tee连用,tee 把内容保存到文档并显示出来。 三、通用后接命令符 -a 所有(all)。 -e 所有(every),比a更详细。 -f 取消保护。 -i 添加提示。 -p 强制执行。 -r 目录管理。 分屏显示的途操作 空格 继续打开下一屏; 回车 继续打开下一行; b 另外开上一屏; f 另外开下一屏; h 帮助; q或Ctrl+C 退出; /字符串 从上往下查找匹配的字符串; ?字符串 从下往上查找匹配的字符串; n 继续查找。 四、退出命令 exit 退出; DOS内部命令 用于退出当前的命令处理器(COMMAND.COM) 恢复前一个命令处理器。 Ctrl+d 跟exit一样效果,表止本次操作。 logout 当csh时可用来退出,其他shell不可用。 clear 清屏,清除(之前的内容并未删除,只是没看到,拉回上面可以看回)。 五、目录管理命令 pwd 显示当前所在目录,打印当前目录的绝对路径。 cd 进入某目录,DOS内部命令 显示或改变当前目录。 cd回车/cd ~ 都是回到自己的主目录。 cd . 当前目录(空格再加一个点)。 cd .. 回到上一级目录(空格再加两个点)。 cd ../.. 向上两级。 cd /user/s0807 从绝对路径去到某目录。 cd ~/s0807 直接进入主目录下的某目录(“cd ~"相当于主目录的路径的简写)。 ls 显示当前目录的所有目录和文件。 用法 ls [-aAbcCdeEfFghHilLmnopqrRstux1@] [file...] ls /etc/ 显示某目录下的所有文件和目录,如etc目录下的。 ls -l (list)列表显示文件(默认按文件名排序), 显示文件的权限、硬链接数(即包含文件数,普通文件是1,目录1+)、用户、组名、大小、修改日期、文件名。 ls -t (time)按修改时间排序,显示目录和文件。 ls -lt 是“-l”和“-t”的组合,按时间顺序显示列表。 ls -F 显示文件类型,目录“/ ”结尾;可执行文件“*”结尾;文本文件(none),没有结尾。 ls -R 递归显示目录结构。即该目录下的文件和各个副目录下的文件都一一显示。 ls -a 显示所有文件,包括隐藏文件。 文件权限 r 读权限。对普通文件来,是读取该文件的权限;对目录来,是获得该目录下的文件信息。 w 写权限。对文件,是修改;对目录,是增删文件与子目录。 (注 删除没有写权限的文件可以用 rm -f ,这是为了操作方便,是人性化的设计)。 x 执行权限;对目录,是进入该目录 - 表示没有权限 形式 - rw- r-- r-- 其 第一个是文件类型(-表普通文件,d表目录,l表软链接文件) 第2~4个是属主,生成文件时登录的人,权限最高,用u表示 第5~7个是属组,系统管理员分配的同组的一个或几个人,用g表示 第8~10个是其他人,除属组外的人,用o表示 所有人,包括属主、属组及其他人,用a表示 chmod 更改权限; 用法 chmod [-fR] <绝对模式> 文件 ... chmod [-fR] <符号模式列表> 文件 ... 其 <符号模式列表> 是一个用逗号分隔的表 [ugoa]{+|-|=}[rwxXlstugo] chmod u+rw 给用户加权限。同理,u-rw也可以减权限。 chmod u=rw 给用户赋权限。与加权限不一样,赋权限有覆盖的效果。 主要形式有如下几种 chmod u+rw chmod u=rw chmod u+r, u+w chmod u+rw,g+w, o+r chmod 777( 用数字的方式设置权限是最常用的) 数字表示权限时,各数位分别表示属主、属组及其他人; 其,1是执行权(Execute),2是写权限(Write),4是读权限(Read), 具体权限相当于三种权限的数相加,如7=1+2+4,即拥有读写和执行权。 另外,临时文件/目录的权限为rwt,可写却不可删,关机后自动删除;建临时目录:chmod 777 目录名,再chmod +t 目录名。 id 显示用户有效的uid(用户字)和gid(组名) 用法 id [-ap] [user] id 显示自己的。 id root 显示root的。 id -a root 显示用户所在组的所有组名(如root用户,是所有组的组员) df 查看文件系统,查看数据区 用法 df [-F FSType] [-abeghklntVvZ] [-o FSType 特定选项] [目录 | 块设备 | 资源] df -k 以kbytes显示文件大小的查看文件系统方式 六、显示文件内容 more 分屏显示文件的内容。 用法 more [-cdflrsuw] [-行] [+行号] [+/模式] [文件名 ...]。 显示7个信息:用户名 密码 用户id(uid) 组id(gid) 描述信息(一般为空) 用户主目录 login shell(登录shell) cat 显示文件内容,不分屏(一般用在小文件,大文件显示不下);合并文件,仅在屏幕上合并,并不改变原文件。 用法 cat [ -usvtebn ] [-|文件] ... tail 实时监控文件,一般用在日志文件,可以只看其的几行。 用法 tail [+/-[n][lbc][f]] [文件] tail [+/-[n][l][r|f]] [文件] 七、文件/目录的增删 echo 显示一行内容。 touch 如果文件/目录不存在,则创建新文件/目录;如果文件存在,那么就是更新该文件的最后访问时间, 用法 touch [-acm] [-r ref_file] 文件... touch [-acm] [MMDDhhmm[yy]] 文件... touch [-acm] [-t [[CC]YY]MMDDhhmm[.SS]] file... mkdir 创建目录(必须有创建目录的权限) 用法 mkdir [-m 模式] [-p] dirname ... mkdir dir1/dir2 在dir1下建dir2 mkdir dir13 dir4 dir5 连建多个 mkdir ~/games 用户主目录下建(默认在当前目录下创建) mkdir -p dir6/dir7/dir8 强制创建dir8;若没有前面的目录,会自动创建dir6和dir7。 不用-p时,若没有dir6/dir7,则创建失败。 cp 复制文件/目录 cp 源文件 目标文件 复制文件;若已有文件则覆盖 cp -r 源目录 目标目录 复制目录;若已有目录则把源目录复制到目标目录下, 没有目标目录时,相当于完全复制源目录,只是文件名不同。 cp beans apple dir2 把beans、apple文件复制到dir2目录下 cp -i beans apple 增加是否覆盖的提示 mv 移动或重命名文件/目录 用法 mv [-f] [-i] f1 f2 mv [-f] [-i] f1 ... fn d1 mv [-f] [-i] d1 d2 mv 源文件名 目标文件名 若目标文件名还没有,则是源文件重命名为目标文件;若目标文件已存在,则源文件覆盖目标文件。 mv 源文件名 目标目录 移动文件 mv 源目录 目标目录 若目标目录不存在,则源目录重命名;若目标目录已存在,则源目录移动到目标目录下。 rm 删除文件/目录 用法 rm [-fiRr] 文件 ... rm 文件名 删除文件。 rm -r 目录名 删除目录。 rm –f 文件 只要是该文件或者目录的拥有者,无论是否有权限删除,都可以用这个命令参数强行删除。 rm -rf * 删除所有文件及目录 rmdir 删除空目录。只可以删除空目录。 ln 创建硬链接或软链接,硬链接=同一文件的多个名字;软链接=快捷方式 用法 ln [-f] [-n] [-s] f1 [f2] ln [-f] [-n] [-s] f1 ... fn d1 ln [-f] [-n] -s d1 d2 ln file1 file1.ln 创建硬链接。感觉是同一文件,删除一个,对另一个没有影响;须两个都删除才算删除。 ln -s file1 file1.sln 创建软链接。可跨系统操作,冲破操作权限;也是快捷方式。 八、时间显示 date 显示时间,精确到秒 用法 date [-u] mmddHHMM[[cc]yy][.SS] date [-u] [+format] date -a [-]sss[.fff] cal 显示日历 cal 9 2008 显示2008年9月的日历; cal 显示当月的 用法 cal [ [月] 年 ] 九、帮助 man 帮助( format and display the on-line manual pages) 用法 man [-] [-adFlrt] [-M 路径] [-T 宏软件包] [-s 段] 名称 ... man [-] [-adFlrt] [-M path] [-T macro-package] [-s section] name... man [-M 路径] -k 关键字 ... man [-M 路径] -f 文件 ... awk 按一定格式输出(pattern scanning and processing language) 用法 awk [-Fc] [-f 源代码 | 'cmds'] [文件] 十、vi 底行模式 /? 命令模式 i a o 输入模式 vi 的使用方法 1、光标 h 左 j 下 k 上 l 右 set nu 显示行号(set nonu) 21 光标停在指定行 21G 第N行 (G到文件尾,1G到文件头) 如果要将光标移动到文件第一行,那么就按 1G H 屏幕头 M 屏幕间 L 屏幕底 ^ 或 shift+6 行首 $ 或 shift+4 行尾 Ctrl+f 下翻 Ctrl+b 上翻 2、输入 (输入模式) o 光标往下换一行 O (大写字母o)在光标所在行上插入一空行 i 在光标所在位置的前面插入字母 a 在光标所在位置的后面插入一个新字母 退出插入状态。 3、修改替换 r 替换一个字符 dd 删除行,剪切行 (5dd删除5行) 5,10d 删除 5 至 10 行(包括第 5行和第 10 行) x 删除一个字符 dw 删除词,剪切词。 ( 3dw删除 3 单词) cw 替换一个单词。 (cw 和 dw 的区别 cw 删除某一个单词后直接进入编辑模式,而dw删除词后仍处于命令模式) cc 替换一行 C 替换从光标到行尾 yy 复制行 (用法同下的 Y ,见下行) Y 将光标移动到要复制行位置,按yy。当你想粘贴的时候,请将光标移动到你想复制的位置的前一个位置,然后按 p yw 复制词 p 当前行下粘贴 1,2co3 复制行1,2在行3之后 4,5m6 移动行4,5在行6之后 u 当你的前一个命令操作是一个误操作的时候,那么可以按一下 u键,即可复原。只能撤销一次 r file2 在光标所在处插入另一个文件 ~ 将字母变成大写 J 可以将当前行与下一行连接起来 /字符串 从上往下找匹配的字符串 ?字符串 从下往上找匹配的字符串 n 继续查找 1,$s/旧串/新串/g 替换全文(或者 %s/旧串/新串/g) (1表示从第一行开始) 没有g则只替换一次,加g替换所有 3、存盘和退出 w 存盘 w newfile 存成新文件 wq 存盘再退出VI(或者ZZ或 X) q! 强行退出不存盘 查看用户 users 显示在线用户(仅显示用户名)。 who 显示在线用户,但比users更详细,包括用户名、终端号、登录时间、IP地址。 who am i 仅显示自己,(但包括用户名、端口、登录时间、IP地址;信息量=who)。 whoami 也仅显示自己,但只有用户名(仅显示自己的有效的用户名)。 w 显示比who更多内容,还包括闲置时间、占CPU、平均占用CPU、执行命令。 用法 w [ -hlsuw ] [ 用户 ] su 改变用户,需再输入密码。 用法 su [-] [ username [ arg ... ] ] su - 相当于退出再重新登录。 查找 find 查找文件 用法 find [-H | -L] 路径列表 谓词列表 find / -name perl 从根目录开始查找名为perl的文件。 find . -mtime 10 -print 从当前目录查找距离现在10天时修改的文件,显示在屏幕上。 (注 “10”表示第10天的时候;如果是“+10”表示10天以外的范围;“-10”表示10天以内的范围。) grep 文件查找字符;有过滤功能,只列出想要的内容 用法 grep -hblcnsviw 模式 文件 . . . 如 grep abc /etc/passwd 在passwd文件下找abc字符 wc 统计 -l 统计行数; -w统计单词数; -c 统计字符数 如 grep wang /etc/passwd|wc -l 统计passwd文件含“wang”的行数 du 查看目录情况 如 du -sk * 不加-s会显示子目录,-k按千字节排序 用法 du [-a] [-d] [-h|-k] [-r] [-o|-s] [-H|-L] [文件...] 进程管理 ps 显示进程。 用法 ps [ -aAdeflcjLPyZ ] [ -o 格式 ] [ -t 项列表 ] [ -u 用户列表 ] [ -U 用户列表 ] [ -G 组列表 ] [ -p 进程列表 ] [ -g 程序组列表 ] [ -s 标识符列表 ] [ -z 区域列表 ] ps 显示自己的进程。 ps -e 显示每个进程,包括空闲进程。 ps -f 显示详情。 ps -ef 组合-e和-f,所有进程的详情。 ps -U uidlist(用户列表) 具体查看某人的进程。 kill pkill sleep jobs 用法 jobs [-l ] fg %n bg %n stop %n 挂起(仅csh能用) Ctrl+C Ctrl+Z 网络链接 ping usage ping host [timeout] usage ping -s [-l | U] [adLnRrv] [-A addr_family] [-c traffic_class] [-g gateway [-g gateway ...]] [-F flow_label] [-I interval] [-i interface] [-P tos] [-p port] [-t ttl] host [data_size] [npackets] ifconfig -a /sbin/ifconfig 查看本机的IP地址 netstat -rn rlogin ftp 帮助文件 [sd0807@localhost ~]$ help GNU bash, version 3.1.17(1)-release (i686-redhat-linux-gnu) These shell commands are defined internally. Type `help' to see this list. Type `help name' to find out more about the function `name'. Use `info bash' to find out more about the shell in general. Use `man -k' or `info' to find out more about commands not in this list. A star (*) next to a name means that the command is disabled. JOB_SPEC [&] (( expression )) . filename [arguments] [ arg... ] [[ expression ]] alias [-p] [name[=value] ... ] bg [job_spec ...] bind [-lpvsPVS] [-m keymap] [-f fi break [n] builtin [shell-builtin [arg ...]] caller [EXPR] case WORD in [PATTERN [| PATTERN]. cd [-L|-P] [dir] command [-pVv] command [arg ...] compgen [-abcdefgjksuv] [-o option complete [-abcdefgjksuv] [-pr] [-o continue [n] declare [-afFirtx] [-p] [name[=val dirs [-clpv] [+N] [-N] disown [-h] [-ar] [jobspec ...] echo [-neE] [arg ...] enable [-pnds] [-a] [-f filename] eval [arg ...] exec [-cl] [-a name] file [redirec exit [n] export [-nf] [name[=value] ...] or false fc [-e ename] [-nlr] [first] [last fg [job_spec] for NAME [in WORDS ... ;] do COMMA for (( exp1; exp2; exp3 )); do COM function NAME { COMMANDS ; } or NA getopts optstring name [arg] hash [-lr] [-p pathname] [-dt] [na help [-s] [pattern ...] history [-c] [-d offset] [n] or hi if COMMANDS; then COMMANDS; [ elif jobs [-lnprs] [jobspec ...] or job kill [-s sigspec | -n signum | -si let arg [arg ...] local name[=value] ... logout popd [+N | -N] [-n] printf [-v var] format [arguments] pushd [dir | +N | -N] [-n] pwd [-LP] read [-ers] [-u fd] [-t timeout] [ readonly [-af] [name[=value] ...] return [n] select NAME [in WORDS ... ;] do CO set [--abefhkmnptuvxBCHP] [-o option] [arg ...] shift [n] shopt [-pqsu] [-o long-option] opt source filename [arguments] suspend [-f] test [expr] time [-p] PIPELINE times trap [-lp] [arg signal_spec ...] true type [-afptP] name [name ...] typeset [-afFirtx] [-p] name[=valu ulimit [-SHacdfilmnpqstuvx] [limit umask [-p] [-S] [mode] unalias [-a] name [name ...] unset [-f] [-v] [name ...] until COMMANDS; do COMMANDS; done variables - Some variable names an wait [n] while COMMANDS; do COMMANDS; done { COMMANDS ; } 输入 man help BASH_BUILTINS(1) BASH_BUILTINS(1) NAME bash, :, ., [, alias, bg, bind, break, builtin, cd, command, compgen, complete, continue, declare, dirs, disown, echo, enable, eval, exec, exit, export, fc, fg, getopts, hash, help, history, jobs, kill, let, local, logout, popd, printf, pushd, pwd, read, readonly, return, set, shift, shopt, source, suspend, test, times, trap, type, typeset, ulimit, umask, una- lias, unset, wait - bash built-in commands, see bash(1) BASH BUILTIN COMMANDS Unless otherwise noted, each builtin command documented in this section as accepting options preceded by - accepts -- to signify the end of the options. For example, the :, true, false, and test builtins do not accept options. : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned. . filename [arguments] source filename [arguments] Read and execute commands from filename in the current shell environment and return the exit status of the last command executed from filename. If filename does not contain a slash, file names in PATH are used to find the directory containing file- name. The file searched for in PATH need not be executable. When bash is not in posix mode, the current directory is searched if no file is found in PATH. If the sourcepath option to the shopt builtin command is turned off, the PATH is not searched. If any arguments are supplied, they become the positional parameters when filename is executed. Otherwise the positional parameters are unchanged. The return status is the status of the last command exited within the script (0 if no commands are executed), and false if filename is not found or cannot be read. alias [-p] [name[=value] ...] Alias with no arguments or with the -p option prints the list of aliases in the form alias name=value on standard output. When arguments are supplied, an alias is defined for each name whose value is given. A trailing space in value causes the next word to be checked for alias substitution when the alias is expanded. For each name in the argument list for which no value is supplied, the name and value of the alias is printed. Alias returns true unless a name is given for which no alias has been defined. bg [jobspec ...] Resume each suspended job jobspec in the background, as if it had been started with &. If jobspec is not present, the shell’s notion of the current job is used. bg jobspec returns 0 unless run when job control is disabled or, when run with job con- trol enabled, any specified jobspec was not found or was started without job control. bind [-m keymap] [-lpsvPSV] bind [-m keymap] [-q function] [-u function] [-r keyseq] bind [-m keymap] -f filename bind [-m keymap] -x keyseq:shell-command bind [-m keymap] keyseq:function-name bind readline-command Display current readline key and function bindings, bind a key sequence to a readline function or macro, or set a readline variable. Each non-option argument is a command as it would appear in .inputrc, but each binding or command must be passed as a sepa- rate argument; e.g., ’"\C-x\C-r": re-read-init-file’. Options, if supplied, have the following meanings: -m keymap Use keymap as the keymap to be affected by the subsequent bindings. Accept- able keymap names are emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-move, vi-command, and vi-insert. vi is equivalent to vi-command; emacs is equivalent to emacs-standard. -l List the names of all readline functions. -p Display readline function names and bindings in such a way that they can be re-read. -P List current readline function names and bindings. -v Display readline variable names and values in such a way that they can be re- read. -V List current readline variable names and values. -s Display readline key sequences bound to macros and the strings they output in such a way that they can be re-read. -S Display readline key sequences bound to macros and the strings they output. -f filename Read key bindings from filename. -q function Query about which keys invoke the named function. -u function Unbind all keys bound to the named function. -r keyseq Remove any current binding for keyseq. -x keyseq:shell-command Cause shell-command to be executed whenever keyseq is entered. The return value is 0 unless an unrecognized option is given or an error occurred. break [n] Exit from within a for, while, until, or select loop. If n is specified, break n levels. n must be ≥ 1. If n is greater than the number of enclosing loops, all enclosing loops are exited. The return value is 0 unless the shell is not executing a loop when break is executed. builtin shell-builtin [arguments] Execute the specified shell builtin, passing it arguments, and return its exit sta- tus. This is useful when defining a function whose name is the same as a shell builtin, retaining the functionality of the builtin within the function. The cd builtin is commonly redefined this way. The return status is false if shell-builtin is not a shell builtin command. cd [-L|-P] [dir] Change the current directory to dir. The variable HOME is the default dir. The variable CDPATH defines the search path for the directory containing dir. Alterna- tive directory names in CDPATH are separated by a colon (:). A null directory name in CDPATH is the same as the current directory, i.e., ‘‘.’’. If dir begins with a slash (/), then CDPATH is not used. The -P option says to use the physical directory structure instead of following symbolic links (see also the -P option to the set builtin command); the -L option forces symbolic links to be followed. An argument of - is equivalent to $OLDPWD. If a non-empty directory name from CDPATH is used, or if - is the first argument, and the directory change is successful, the absolute path- name of the new working directory is written to the standard output. The return value is true if the directory was successfully changed; false otherwise. caller [expr] Returns the context of any active subroutine call (a shell function or a script exe- cuted with the . or source builtins. Without expr, caller displays the line number and source filename of the current subroutine call. If a non-negative integer is supplied as expr, caller displays the line number, subroutine name, and source file corresponding to that position in the current execution call stack. This extra information may be used, for example, to print a stack trace. The current frame is frame 0. The return value is 0 unless the shell is not executing a subroutine call or expr does not correspond to a valid position in the call stack. command [-pVv] command [arg ...] Run command with args suppressing the normal shell function lookup. Only builtin com- mands or commands found in the PATH are executed. If the -p option is given, the search for command is performed using a default value for PATH that is guaranteed to find all of the standard utilities. If either the -V or -v option is supplied, a description of command is printed. The -v option causes a single word indicating the command or file name used to invoke command to be displayed; the -V option produces a more verbose description. If the -V or -v option is supplied, the exit status is 0 if command was found, and 1 if not. If neither option is supplied and an error occurred or command cannot be found, the exit status is 127. Otherwise, the exit status of the command builtin is the exit status of command. compgen [option] [word] Generate possible completion matches for word according to the options, which may be any option accepted by the complete builtin with the exception of -p and -r, and write the matches to the standard output. When using the -F or -C options, the vari- ous shell variables set by the programmable completion facilities, while available, will not have useful values. The matches will be generated in the same way as if the programmable completion code had generated them directly from a completion specification with the same flags. If word is specified, only those completions matching word will be displayed. The return value is true unless an invalid option is supplied, or no matches were generated. complete [-abcdefgjksuv] [-o comp-option] [-A action] [-G globpat] [-W wordlist] [-P prefix] [-S suffix] [-X filterpat] [-F function] [-C command] name [name ...] complete -pr [name ...] Specify how arguments to each name should be completed. If the -p option is sup- plied, or if no options are supplied, existing completion specifications are printed in a way that allows them to be reused as input. The -r option removes a completion specification for each name, or, if no names are supplied, all completion specifica- tions. The process of applying these completion specifications when word completion is attempted is described above under Programmable Completion. Other options, if specified, have the following meanings. The arguments to the -G, -W, and -X options (and, if necessary, the -P and -S options) should be quoted to protect them from expansion before the complete builtin is invoked. -o comp-option The comp-option controls several aspects of the compspec’s behavior beyond the simple generation of completions. comp-option may be one of: bashdefault Perform the rest of the default bash completions if the compspec gen- erates no matches. default Use readline’s default filename completion if the compspec generates no matches. dirnames Perform directory name completion if the compspec generates no matches. filenames Tell readline that the compspec generates filenames, so it can per- form any filename-specific processing (like adding a slash to direc- tory names or suppressing trailing spaces). Intended to be used with shell functions. nospace Tell readline not to append a space (the default) to words completed at the end of the line. plusdirs After any matches defined by the compspec are generated, directory name completion is attempted and any matches are added to the results of the other actions. -A action The action may be one of the following to generate a list of possible comple- tions: alias Alias names. May also be specified as -a. arrayvar Array variable names. binding Readline key binding names. builtin Names of shell builtin commands. May also be specified as -b. command Command names. May also be specified as -c. directory Directory names. May also be specified as -d. disabled Names of disabled shell builtins. enabled Names of enabled shell builtins. export Names of exported shell variables. May also be specified as -e. file File names. May also be specified as -f. function Names of shell functions. group Group names. May also be specified as -g. helptopic Help topics as accepted by the help builtin. hostname Hostnames, as taken from the file specified by the HOSTFILE shell variable. job Job names, if job control is active. May also be specified as -j. keyword Shell reserved words. May also be specified as -k. running Names of running jobs, if job control is active. service Service names. May also be specified as -s. setopt Valid arguments for the -o option to the set builtin. shopt Shell option names as accepted by the shopt builtin. signal Signal names. stopped Names of stopped jobs, if job control is active. user User names. May also be specified as -u. variable Names of all shell variables. May also be specified as -v. -G globpat The filename expansion pattern globpat is expanded to generate the possible completions. -W wordlist The wordlist is split using the characters in the IFS special variable as delimiters, and each resultant word is expanded. The possible completions are the members of the resultant list which match the word being completed. -C command command is executed in a subshell environment, and its output is used as the possible completions. -F function The shell function function is executed in the current shell environment. When it finishes, the possible completions are retrieved from the value of the COMPREPLY array variable. -X filterpat filterpat is a pattern as used for filename expansion. It is applied to the list of possible completions generated by the preceding options and argu- ments, and each completion matching filterpat is removed from the list. A leading ! in filterpat negates the pattern; in this case, any completion not matching filterpat is removed. -P prefix prefix is added at the beginning of each possible completion after all other options have been applied. -S suffix suffix is appended to each possible completion after all other options have been applied. The return value is true unless an invalid option is supplied, an option other than -p or -r is supplied without a name argument, an attempt is made to remove a comple- tion specification for a name for which no specification exists, or an error occurs adding a completion specification. continue [n] Resume the next iteration of the enclosing for, while, until, or select loop. If n is specified, resume at the nth enclosing loop. n must be ≥ 1. If n is greater than the number of enclosing loops, the last enclosing loop (the ‘‘top-level’’ loop) is resumed. The return value is 0 unless the shell is not executing a loop when con- tinue is executed. declare [-afFirtx] [-p] [name[=value] ...] typeset [-afFirtx] [-p] [name[=value] ...] Declare variables and/or give them attributes. If no names are given then display the values of variables. The -p option will display the attributes and values of each name. When -p is used, additional options are ignored. The -F option inhibits the display of function definitions; only the function name and attributes are printed. If the extdebug shell option is enabled using shopt, the source file name and line number where the function is defined are displayed as well. The -F option implies -f. The following options can be used to restrict output to variables with the specified attribute or to give variables attributes: -a Each name is an array variable (see Arrays above). -f Use function names only. -i The variable is treated as an integer; arithmetic evaluation (see ARITHMETIC EVALUATION ) is performed when the variable is assigned a value. -r Make names readonly. These names cannot then be assigned values by subsequent assignment statements or unset. -t Give each name the trace attribute. Traced functions inherit the DEBUG and RETURN traps from the calling shell. The trace attribute has no special mean- ing for variables. -x Mark names for export to subsequent commands via the environment. Using ‘+’ instead of ‘-’ turns off the attribute instead, with the exception that +a may not be used to destroy an array variable. When used in a function, makes each name local, as with the local command. If a variable name is followed by =value, the value of the variable is set to value. The return value is 0 unless an invalid option is encountered, an attempt is made to define a function using ‘‘-f foo=bar’’, an attempt is made to assign a value to a readonly variable, an attempt is made to assign a value to an array variable without using the compound assignment syntax (see Arrays above), one of the names is not a valid shell variable name, an attempt is made to turn off readonly status for a readonly variable, an attempt is made to turn off array status for an array variable, or an attempt is made to display a non-exis- tent function with -f. dirs [-clpv] [+n] [-n] Without options, displays the list of currently remembered directories. The default display is on a single line with directory names separated by spaces. Directories are added to the list with the pushd command; the popd command removes entries from the list. +n Displays the nth entry counting from the left of the list shown by dirs when invoked without options, starting with zero. -n Displays the nth entry counting from the right of the list shown by dirs when invoked without options, starting with zero. -c Clears the directory stack by deleting all of the entries. -l Produces a longer listing; the default listing format uses a tilde to denote the home directory. -p Print the directory stack with one entry per line. -v Print the directory stack with one entry per line, prefixing each entry with its index in the stack. The return value is 0 unless an invalid option is supplied or n indexes beyond the end of the directory stack. disown [-ar] [-h] [jobspec ...] Without options, each jobspec is removed from the table of active jobs. If the -h option is given, each jobspec is not removed from the table, but is marked so that SIGHUP is not sent to the job if the shell receives a SIGHUP. If no jobspec is present, and neither the -a nor the -r option is supplied, the current job is used. If no jobspec is supplied, the -a option means to remove or mark all jobs; the -r option without a jobspec argument restricts operation to running jobs. The return value is 0 unless a jobspec does not specify a valid job. echo [-neE] [arg ...] Output the args, separated by spaces, followed by a newline. The return status is always 0. If -n is specified, the trailing newline is suppressed. If the -e option is given, interpretation of the following backslash-escaped characters is enabled. The -E option disables the interpretation of these escape characters, even on systems where they are interpreted by default. The xpg_echo shell option may be used to dynamically determine whether or not echo expands these escape characters by default. echo does not interpret -- to mean the end of options. echo interprets the following escape sequences: \a alert (bell) \b backspace \c suppress trailing newline \e an escape character \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \\ backslash \0nnn the eight-bit character whose value is the octal value nnn (zero to three octal digits) \nnn the eight-bit character whose value is the octal value nnn (one to three octal digits) \xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits) enable [-adnps] [-f filename] [name ...] Enable and disable builtin shell commands. Disabling a builtin allows a disk command which has the same name as a shell builtin to be executed without specifying a full pathname, even though the shell normally searches for builtins before disk commands. If -n is used, each name is disabled; otherwise, names are enabled. For example, to use the test binary found via the PATH instead of the shell builtin version, run ‘‘enable -n test’’. The -f option means to load the new builtin command name from shared object filename, on systems that support dynamic loading. The -d option will delete a builtin previously loaded with -f. If no name arguments are given, or if the -p option is supplied, a list of shell builtins is printed. With no other option arguments, the list consists of all enabled shell builtins. If -n is supplied, only disabled builtins are printed. If -a is supplied, the list printed includes all builtins, with an indication of whether or not each is enabled. If -s is supplied, the output is restricted to the POSIX special builtins. The return value is 0 unless a name is not a shell builtin or there is an error loading a new builtin from a shared object. eval [arg ...] The args are read and concatenated together into a single command. This command is then read and executed by the shell, and its exit status is returned as the value of eval. If there are no args, or only null arguments, eval returns 0. exec [-cl] [-a name] [command [arguments]] If command is specified, it replaces the shell. No new process is created. The arguments become the arguments to command. If the -l option is supplied, the shell places a dash at the beginning of the zeroth arg passed to command. This is what login(1) does. The -c option causes command to be executed with an empty environ- ment. If -a is supplied, the shell passes name as the zeroth argument to the exe- cuted command. If command cannot be executed for some reason, a non-interactive shell exits, unless the shell option execfail is enabled, in which case it returns failure. An interactive shell returns failure if the file cannot be executed. If command is not specified, any redirections take effect in the current shell, and the return status is 0. If there is a redirection error, the return status is 1. exit [n] Cause the shell to exit with a status of n. If n is omitted, the exit status is that of the last command executed. A trap on EXIT is executed before the shell termi- nates. export [-fn] [name[=word]] ... export -p The supplied names are marked for automatic export to the environment of subsequently executed commands. If the -f option is given, the names refer to functions. If no names are given, or if the -p option is supplied, a list of all names that are exported in this shell is printed. The -n option causes the export property to be removed from each name. If a variable name is followed by =word, the value of the variable is set to word. export returns an exit status of 0 unless an invalid option is encountered, one of the names is not a valid shell variable name, or -f is sup- plied with a name that is not a function. fc [-e ename] [-nlr] [first] [last] fc -s [pat=rep] [cmd] Fix Command. In the first form, a range of commands from first to last is selected from the history list. First and last may be specified as a string (to locate the last command beginning with that string) or as a number (an index into the history list, where a negative number is used as an offset from the current command number). If last is not specified it is set to the current command for listing (so that ‘‘fc -l -10’’ prints the last 10 commands) and to first otherwise. If first is not speci- fied it is set to the previous command for editing and -16 for listing. The -n option suppresses the command numbers when listing. The -r option reverses the order of the commands. If the -l option is given, the commands are listed on standard output. Otherwise, the editor given by ename is invoked on a file contain- ing those commands. If ename is not given, the value of the FCEDIT variable is used, and the value of EDITOR if FCEDIT is not set. If neither variable is set, is used. When editing is complete, the edited commands are echoed and executed. In the second form, command is re-executed after each instance of pat is replaced by rep. A useful alias to use with this is ‘‘r="fc -s"’’, so that typing ‘‘r cc’’ runs the last command beginning with ‘‘cc’’ and typing ‘‘r’’ re-executes the last command. If the first form is used, the return value is 0 unless an invalid option is encoun- tered or first or last specify history lines out of range. If the -e option is sup- plied, the return value is the value of the last command executed or failure if an error occurs with the temporary file of commands. If the second form is used, the return status is that of the command re-executed, unless cmd does not specify a valid history line, in which case fc returns failure. fg [jobspec] Resume jobspec in the foreground, and make it the current job. If jobspec is not present, the shell’s notion of the current job is used. The return value is that of the command placed into the foreground, or failure if run when job control is dis- abled or, when run with job control enabled, if jobspec does not specify a valid job or jobspec specifies a job that was started without job control. getopts optstring name [args] getopts is used by shell procedures to parse positional parameters. optstring con- tains the option characters to be recognized; if a character is followed by a colon, the option is expected to have an argument, which should be separated from it by white space. The colon and question mark characters may not be used as option char- acters. Each time it is invoked, getopts places the next option in the shell vari- able name, initializing name if it does not exist, and the index of the next argument to be processed into the variable OPTIND. OPTIND is initialized to 1 each time the shell or a shell script is invoked. When an option requires an argument, getopts places that argument into the variable OPTARG. The shell does not reset OPTIND auto- matically; it must be manually reset between multiple calls to getopts within the same shell invocation if a new set of parameters is to be used. When the end of options is encountered, getopts exits with a return value greater than zero. OPTIND is set to the index of the first non-option argument, and name is set to ?. getopts normally parses the positional parameters, but if more arguments are given in args, getopts parses those instead. getopts can report errors in two ways. If the first character of optstring is a colon, silent error reporting is used. In normal operation diagnostic messages are printed when invalid options or missing option arguments are encountered. If the variable OPTERR is set to 0, no error messages will be displayed, even if the first character of optstring is not a colon. If an invalid option is seen, getopts places ? into name and, if not silent, prints an error message and unsets OPTARG. If getopts is silent, the option character found is placed in OPTARG and no diagnostic message is printed. If a required argument is not found, and getopts is not silent, a question mark (?) is placed in name, OPTARG is unset, and a diagnostic message is printed. If getopts is silent, then a colon (:) is placed in name and OPTARG is set to the option charac- ter found. getopts returns true if an option, specified or unspecified, is found. It returns false if the end of options is encountered or an error occurs. hash [-lr] [-p filename] [-dt] [name] For each name, the full file name of the command is determined by searching the directories in $PATH and remembered. If the -p option is supplied, no path search is performed, and filename is used as the full file name of the command. The -r option causes the shell to forget all remembered locations. The -d option causes the shell to forget the remembered location of each name. If the -t option is supplied, the full pathname to which each name corresponds is printed. If multiple name arguments are supplied with -t, the name is printed before the hashed full pathname. The -l option causes output to be displayed in a format that may be reused as input. If no arguments are given, or if only -l is supplied, information about remembered commands is printed. The return status is true unless a name is not found or an invalid option is supplied. help [-s] [pattern] Display helpful information about builtin commands. If pattern is specified, help gives detailed help on all commands matching pattern; otherwise help for all the builtins and shell control structures is printed. The -s option restricts the infor- mation displayed to a short usage synopsis. The return status is 0 unless no command matches pattern. history [n] history -c history -d offset history -anrw [filename] history -p arg [arg ...] history -s arg [arg ...] With no options, display the command history list with line numbers. Lines listed with a * have been modified. An argument of n lists only the last n lines. If the shell variable HISTTIMEFORMAT is set and not null, it is used as a format string for strftime(3) to display the time stamp associated with each displayed history entry. No intervening blank is printed between the formatted time stamp and the history line. If filename is supplied, it is used as the name of the history file; if not, the value of HISTFILE is used. Options, if supplied, have the following meanings: -c Clear the history list by deleting all the entries. -d offset Delete the history entry at position offset. -a Append the ‘‘new’’ history lines (history lines entered since the beginning of the current bash session) to the history file. -n Read the history lines not already read from the history file into the current history list. These are lines appended to the history file since the begin- ning of the current bash session. -r Read the contents of the history file and use them as the current history. -w Write the current history to the history file, overwriting the history file’s contents. -p Perform history substitution on the following args and display the result on the standard output. Does not store the results in the history list. Each arg must be quoted to disable normal history expansion. -s Store the args in the history list as a single entry. The last command in the history list is removed before the args are added. If the HISTTIMEFORMAT is set, the time stamp information associated with each history entry is written to the history file. The return value is 0 unless an invalid option is encountered, an error occurs while reading or writing the history file, an invalid offset is supplied as an argument to -d, or the history expansion supplied as an argument to -p fails. jobs [-lnprs] [ jobspec ... ] jobs -x command [ args ... ] The first form lists the active jobs. The options have the following meanings: -l List process IDs in addition to the normal information. -p List only the process ID of the job’s process group leader. -n Display information only about jobs that have changed status since the user was last notified of their status. -r Restrict output to running jobs. -s Restrict output to stopped jobs. If jobspec is given, output is restricted to information about that job. The return status is 0 unless an invalid option is encountered or an invalid jobspec is sup- plied. If the -x option is supplied, jobs replaces any jobspec found in command or args with the corresponding process group ID, and executes command passing it args, returning its exit status. kill [-s sigspec | -n signum | -sigspec] [pid | jobspec] ... kill -l [sigspec | exit_status] Send the signal named by sigspec or signum to the processes named by pid or jobspec. sigspec is either a case-insensitive signal name such as SIGKILL (with or without the SIG prefix) or a signal number; signum is a signal number. If sigspec is not present, then SIGTERM is assumed. An argument of -l lists the signal names. If any arguments are supplied when -l is given, the names of the signals corresponding to the arguments are listed, and the return status is 0. The exit_status argument to -l is a number specifying either a signal number or the exit status of a process termi- nated by a signal. kill returns true if at least one signal was successfully sent, or false if an error occurs or an invalid option is encountered. let arg [arg ...] Each arg is an arithmetic expression to be evaluated (see ARITHMETIC EVALUATION). If the last arg evaluates to 0, let returns 1; 0 is returned otherwise. local [option] [name[=value] ...] For each argument, a local variable named name is created, and assigned value. The option can be any of the options accepted by declare. When local is used within a function, it causes the variable name to have a visible scope restricted to that function and its children. With no operands, local writes a list of local variables to the standard output. It is an error to use local when not within a function. The return status is 0 unless local is used outside a function, an invalid name is sup- plied, or name is a readonly variable. logout Exit a login shell. popd [-n] [+n] [-n] Removes entries from the directory stack. With no arguments, removes the top direc- tory from the stack, and performs a cd to the new top directory. Arguments, if sup- plied, have the following meanings: +n Removes the nth entry counting from the left of the list shown by dirs, start- ing with zero. For example: ‘‘popd +0’’ removes the first directory, ‘‘popd +1’’ the second. -n Removes the nth entry counting from the right of the list shown by dirs, starting with zero. For example: ‘‘popd -0’’ removes the last directory, ‘‘popd -1’’ the next to last. -n Suppresses the normal change of directory when removing directories from the stack, so that only the stack is manipulated. If the popd command is successful, a dirs is performed as well, and the return status is 0. popd returns false if an invalid option is encountered, the directory stack is empty, a non-existent directory stack entry is specified, or the directory change fails. printf [-v var] format [arguments] Write the formatted arguments to the standard output under the control of the format. The format is a character string which contains three types of objects: plain charac- ters, which are simply copied to standard output, character escape sequences, which are converted and copied to the standard output, and format specifications, each of which causes printing of the next successive argument. In addition to the standard printf(1) formats, %b causes printf to expand backslash escape sequences in the cor- responding argument (except that \c terminates output, backslashes in \', \", and \? are not removed, and octal escapes beginning with \0 may contain up to four digits), and %q causes printf to output the corresponding argument in a format that can be reused as shell input. The -v option causes the output to be assigned to the variable var rather than being printed to the standard output. The format is reused as necessary to consume all of the arguments. If the format requires more arguments than are supplied, the extra format specifications behave as if a zero value or null string, as appropriate, had been supplied. The return value is zero on success, non-zero on failure. pushd [-n] [dir] pushd [-n] [+n] [-n] Adds a directory to the top of the directory stack, or rotates the stack, making the new top of the stack the current working directory. With no arguments, exchanges the top two directories and returns 0, unless the directory stack is empty. Arguments, if supplied, have the following meanings: +n Rotates the stack so that the nth directory (counting from the left of the list shown by dirs, starting with zero) is at the top. -n Rotates the stack so that the nth directory (counting from the right of the list shown by dirs, starting with zero) is at the top. -n Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated. dir Adds dir to the directory stack at the top, making it the new current working directory. If the pushd command is successful, a dirs is performed as well. If the first form is used, pushd returns 0 unless the cd to dir fails. With the second form, pushd returns 0 unless the directory stack is empty, a non-existent directory stack element is specified, or the directory change to the specified new current directory fails. pwd [-LP] Print the absolute pathname of the current working directory. The pathname printed contains no symbolic links if the -P option is supplied or the -o physical option to the set builtin command is enabled. If the -L option is used, the pathname printed may contain symbolic links. The return status is 0 unless an error occurs while reading the name of the current directory or an invalid option is supplied. read [-ers] [-u fd] [-t timeout] [-a aname] [-p prompt] [-n nchars] [-d delim] [name ...] One line is read from the standard input, or from the file descriptor fd supplied as an argument to the -u option, and the first word is assigned to the first name, the second word to the second name, and so on, with leftover words and their intervening separators assigned to the last name. If there are fewer words read from the input stream than names, the remaining names are assigned empty values. The characters in IFS are used to split the line into words. The backslash character (\) may be used to remove any special meaning for the next character read and for line continuation. Options, if supplied, have the following meanings: -a aname The words are assigned to sequential indices of the array variable aname, starting at 0. aname is unset before any new values are assigned. Other name arguments are ignored. -d delim The first character of delim is used to terminate the input line, rather than newline. -e If the standard input is coming from a terminal, readline (see READLINE above) is used to obtain the line. -n nchars read returns after reading nchars characters rather than waiting for a com- plete line of input. -p prompt Display prompt on standard error, without a trailing newline, before attempt- ing to read any input. The prompt is displayed only if input is coming from a terminal. -r Backslash does not act as an escape character. The backslash is considered to be part of the line. In particular, a backslash-newline pair may not be used as a line continuation. -s Silent mode. If input is coming from a terminal, characters are not echoed. -t timeout Cause read to time out and return failure if a complete line of input is not read within timeout seconds. This option has no effect if read is not reading input from the terminal or a pipe. -u fd Read input from file descriptor fd. If no names are supplied, the line read is assigned to the variable REPLY. The return code is zero, unless end-of-file is encountered, read times out, or an invalid file descriptor is supplied as the argument to -u. readonly [-apf] [name[=word] ...] The given names are marked readonly; the values of these names may not be changed by subsequent assignment. If the -f option is supplied, the functions corresponding to the names are so marked. The -a option restricts the variables to arrays. If no name arguments are given, or if the -p option is supplied, a list of all readonly names is printed. The -p option causes output to be displayed in a format that may be reused as input. If a variable name is followed by =word, the value of the vari- able is set to word. The return status is 0 unless an invalid option is encountered, one of the names is not a valid shell variable name, or -f is supplied with a name that is not a function. return [n] Causes a function to exit with the return value specified by n. If n is omitted, the return status is that of the last command executed in the function body. If used outside a function, but during execution of a script by the . (source) command, it causes the shell to stop executing that script and return either n or the exit status of the last command executed within the script as the exit status of the script. If used outside a function and not during execution of a script by ., the return status is false. Any command associated with the RETURN trap is executed before execution resumes after the function or script. set [--abefhkmnptuvxBCHP] [-o option] [arg ...] Without options, the name and value of each shell variable are displayed in a format that can be reused as input for setting or resetting the currently-set variables. Read-only variables cannot be reset. In posix mode, only shell variables are listed. The output is sorted according to the current locale. When options are specified, they set or unset shell attributes. Any arguments remaining after the options are processed are treated as values for the positional parameters and are assigned, in order, to $1, $2, ... $n. Options, if specified, have the following meanings: -a Automatically mark variables and functions which are modified or created for export to the environment of subsequent commands. -b Report the status of terminated background jobs immediately, rather than before the next primary prompt. This is effective only when job control is enabled. -e Exit immediately if a simple command (see SHELL GRAMMAR above) exits with a non-zero status. The shell does not exit if the command that fails is part of the command list immediately following a while or until keyword, part of the test in an if statement, part of a && or ││ list, or if the command’s return value is being inverted via !. A trap on ERR, if set, is executed before the shell exits. -f Disable pathname expansion. -h Remember the location of commands as they are looked up for execution. This is enabled by default. -k All arguments in the form of assignment statements are placed in the environ- ment for a command, not just those that precede the command name. -m Monitor mode. Job control is enabled. This option is on by default for interactive shells on systems that support it (see JOB CONTROL above). Back- ground processes run in a separate process group and a line containing their exit status is printed upon their completion. -n Read commands but do not execute them. This may be used to check a shell script for syntax errors. This is ignored by interactive shells. -o option-name The option-name can be one of the following: allexport Same as -a. braceexpand Same as -B. emacs Use an emacs-style command line editing interface. This is enabled by default when the shell is interactive, unless the shell is started with the --noediting option. errtrace Same as -E. functrace Same as -T. errexit Same as -e. hashall Same as -h. histexpand Same as -H. history Enable command history, as described above under HISTORY. This option is on by default in interactive shells. ignoreeof The effect is as if the shell command ‘‘IGNOREEOF=10’’ had been exe- cuted (see Shell Variables above). keyword Same as -k. monitor Same as -m. noclobber Same as -C. noexec Same as -n. noglob Same as -f. nolog Currently ignored. notify Same as -b. nounset Same as -u. onecmd Same as -t. physical Same as -P. pipefail If set, the return value of a pipeline is the value of the last (rightmost) command to exit with a non-zero status, or zero if all command

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