PHP. Руководство по PHP. 2005
posix_setegid
posix_setegid
(PHP4>= 4.0.2, PHP5)posix_setegid --
Set the effective GID of the current process
Description
bool posix_setegid (int gid)
Set the effective 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.
Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки.
posix_mknod
posix_seteuid