[挑战难题]如何快速读取一个超长文本文件

#include <windows.h>

#include <stdio.h>

#include <conio.h>



#define BUF_SIZE 256

TCHAR szName[]=TEXT("MyFileMappingObject");

TCHAR szMsg[]=TEXT("Message from first process");

TCHAR szFileName[]=TEXT("xxx.txt");



void main()

{

   HANDLE hMapFile, hFile;

   LPCTSTR pBuf;



   hFile = CreateFile(szFileName,    // file to open

                   GENERIC_READ,          // open for reading

                   FILE_SHARE_READ,       // share for reading

                   NULL,                  // default security

                   OPEN_EXISTING,         // existing file only

                   FILE_ATTRIBUTE_NORMAL, // normal file

                   NULL);                 // no attr. template

 

   if (hFile == INVALID_HANDLE_VALUE) 

   { 

       printf("Could not open file (error %d)\n", GetLastError());

       return 0;

   }



   hMapFile = CreateFileMapping(

                 hFile,    

                 NULL,                    // default security 

                 PAGE_READWRITE,          // read/write access

                 0,                       // max. object size 

                 BUF_SIZE,                // buffer size  

                 szName);                 // name of mapping object

 

   if (hMapFile == NULL || hMapFile == INVALID_HANDLE_VALUE) 

   { 

      printf("Could not create file mapping object (%d).\n", 

             GetLastError());

      return;

   }

   pBuf = (LPTSTR) MapViewOfFile(hMapFile,   // handle to map object

                        FILE_MAP_ALL_ACCESS, // read/write permission

                        0,                   

                        0,                   

                        BUF_SIZE);           

 

   if (pBuf == NULL) 

   { 

      printf("Could not map view of file (%d).\n", 

             GetLastError()); 

      return;

   }





   //在这里访问pBuf，就是访问文件





   UnmapViewOfFile(pBuf);



   CloseHandle(hMapFile);

   CloseHandle(hFile);

}