getpid是什么函数？

[ciahi]

这函数在标准库里面根本没有，还有其他一些函数，在Win-TC中可以用，但是在标准库中找不到
这样的函数是什么函数？

[sopro]

符合POSIX规范的linux/unix必须提供的库函数
返回进程ID

[jixingzhong]

它不是 标准库中的函数 ...

NAME
getpid - get the process ID
SYNOPSIS
#include <unistd.h>

pid_t getpid(void);


DESCRIPTION
The getpid() function shall return the process ID of the calling process.

RETURN VALUE
The getpid() function shall always be successful and no return value is reserved to indicate an error.

ERRORS
No errors are defined.


--------------------------------------------------------------------------------

The following sections are informative.
EXAMPLES
None.

APPLICATION USAGE
None.

RATIONALE
None.

FUTURE DIRECTIONS
None.

SEE ALSO
exec(), fork(), getpgrp(), getppid(), kill(), setpgid(), setsid(), the Base Definitions volume of IEEE Std 1003.1-2001, <sys/types.h>, <unistd.h>

CHANGE HISTORY
First released in Issue 1. Derived from Issue 1 of the SVID.

Issue 6
In the SYNOPSIS, the optional include of the <sys/types.h> header is removed.

The following new requirements on POSIX implementations derive from alignment with the Single UNIX Specification:

The requirement to include <sys/types.h> has been removed. Although <sys/types.h> was required for conforming implementations of previous POSIX specifications, it was not required for UNIX applications.

[laiwusheng]

像这样的 见名就可以知义

[iambic]

操作系统提供的库函数。

[ciahi]

#include <stdio.h>
#include <process.h>

void main (void)
{
printf("Process id: %X\n", getpid());
}

这个例子中没有包含unistd.h头文件呀？但是可以正常运行
在Win-TC的库中也没有这个文件

在哪儿可以查看这些函数的定义？？？

[lockhall]

yes

上次看fork（）就没想到是在unix下的函数～～～hoho

[gjb999]

见名知意

[liubingqian]

这是POSIX的东西，有空看看《UNIX环境高级编程》吧。