kill_pgrp
kill_pgrp(pgrp, SIGWINCH, 1);
kill_pgrp(tty_pgrp, sig, 1);
kill_pgrp(pgrp, sig, 1);
kill_pgrp(pgrp, SIGWINCH, 1);
kill_pgrp(rpgrp, SIGWINCH, 1);
kill_pgrp(pgrp, SIGWINCH, 1);
kill_pgrp(tty_pgrp, SIGHUP, exit_session);
kill_pgrp(tty_pgrp, SIGHUP, on_exit);
kill_pgrp(tty_pgrp, SIGCONT, on_exit);
kill_pgrp(old_pgrp, SIGHUP, on_exit);
kill_pgrp(old_pgrp, SIGCONT, on_exit);
kill_pgrp(pgrp, sig, 1);
extern int kill_pgrp(struct pid *pid, int sig, int priv);
EXPORT_SYMBOL(kill_pgrp);