(PHP 3>= 3.0.13, PHP 4 >= 4.0.0)

posix_setgid --  Set the effective GID of the current process


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.

Returns TRUE on success, FALSE otherwise.