.\" Copyright (c) 1980, 1991 Regents of the University of California.
.\" %sccs.include.redist.man%
.\" @(#)killpg.2 6.5 (Berkeley) %G%
.Nd send signal to a process group
.Fd #include <sys/signal.h>
.Fn killpg "pid_t pgrp" "int sig"
sends the signal to the sending process's process group.
The sending process and members of the process group must
have the same effective user ID, or
the sender must be the super-user.
As a single special case the continue signal SIGCONT may be sent
to any process that is a descendant of the current process.
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned and the global variable
is set to indicate the error.
will fail and no signal will be sent if:
is not a valid signal number.
No process can be found in the process group specified by
The process group was given as 0
but the sending process does not have a process group.
The sending process is not the super-user and one or more
of the target processes has an effective user ID different from that
function call appeared in