posix_setgid

(PHP 3>= 3.0.13, PHP 4 , PHP 5)

posix_setgid --  Set the GID of the current process

Description

bool posix_setgid ( int gid)

Set the real group ID of the current process. This is a privileged function and you need appropriate privileges (usually root) on your system to be able to perform this function. The appropriate order of function calls is posix_setgid() first, posix_setuid() last.

如果成功则返回 TRUE,失败则返回 FALSE