posix_setpgid
    (PHP 3>= 3.0.13, PHP 4 , PHP 5)
posix_setpgid -- Set process group id for job control
Description
int 
posix_setpgid ( int pid, int pgid)
     Let the process pid join the process group
     pgid. See POSIX.1 and the setsid(2) manual
     page on your POSIX system for more informations on process groups
     and job control. Returns TRUE on success or FALSE on failure.