经常看到exit(1),exit(-1),exit(0),exit(status)的参数到底各代表啥意思？

[booming]

经常看到exit(1),exit(-1),exit(0),exit(status)的参数到底各代表啥意思？

[canany1tellme]

没什么意思，一般来说exit的参数是进程的返回码，一般是错误码，0表示没有错误，不过你可以自己定义

[hiiiiiijiang]

The exit and _exit functions terminate the calling process. exit calls, in last-in-first-out (LIFO) order, the functions registered by atexit and _onexit, then flushes all file buffers before terminating the process. _exit terminates the process without processing atexit or _onexit or flushing stream buffers. The status value is typically set to 0 to indicate a normal exit and set to some other value to indicate an error.

Although the exit and _exit calls do not return a value, the low-order byte of status is made available to the waiting calling process, if one exists, after the calling process exits. The status value is available to the operating-system batch command ERRORLEVEL and is represented by one of two constants: EXIT_SUCCESS, which represents a value of 0, or EXIT_FAILURE, which represents a value of 1. The behavior of exit, _exit, _cexit, and _c_exit is as follows.

Function Description
exit Performs complete C library termination procedures, terminates the process, and exits with the supplied status code.
_exit Performs “quick” C library termination procedures, terminates the process, and exits with the supplied status code.
_cexit Performs complete C library termination procedures and returns to the caller, but does not terminate the process.
_c_exit Performs “quick” C library termination procedures and returns to the caller, but does not terminate the process.


Example

/* EXITER.C: This program prompts the user for a yes
* or no and returns an exit code of 1 if the
* user answers Y or y; otherwise it returns 0. The
* error code could be tested in a batch file.
*/

#include <conio.h>
#include <stdlib.h>

void main( void )
{
int ch;

_cputs( "Yes or no? " );
ch = _getch();
_cputs( "\r\n" );
if( toupper( ch ) == 'Y' )
exit( 1 );
else
exit( 0 );
}

[guangsan]

就是一个指定的进程退出代码。如果是一个单一的程序，status是0，－1，1都一样使程序退出（不知道这个退出代码如何处理）。

如果是一个子进程，可以使用GetExitCodeProcess获得退出代码，然后进行处理。



但是在面向对象的环境中由于exit()和abort()不销毁对象请不要在面向对象环境中使用abort()和exit()。

[liudaqin]

学习

[angelcool]

知识