killpg — send signal to a process group
#include <signal.h>
int
killpg( |
int | pgrp, |
int | sig) ; |
Note | |||
---|---|---|---|
|
killpg
() sends the signal
sig
to the process
group pgrp
. See
signal(7) for a list of
signals.
If pgrp
is 0,
killpg
() sends the signal to
the calling process's process group. (POSIX says: If
pgrp
is less than or
equal to 1, the behavior is undefined.)
For a process to have permission to send a signal it must
either be privileged (under Linux: have the CAP_KILL
capability), or the real or
effective user ID of the sending process must equal the real
or saved set-user-ID of the target process. In the case of
SIGCONT
it suffices when the
sending and receiving processes belong to the same
session.
On success, zero is returned. On error, −1 is
returned, and errno
is set
appropriately.
Sig
is not a
valid signal number.
The process does not have permission to send the signal to any of the target processes.
No process can be found in the process group
specified by pgrp
.
The process group was given as 0 but the sending process does not have a process group.
There are various differences between the permission
checking in BSD-type systems and System V-type systems. See
the POSIX rationale for kill
().
A difference not mentioned by POSIX concerns the return value
EPERM: BSD documents that no
signal is sent and EPERM
returned when the permission check failed for at least one
target process, while POSIX documents EPERM only when the permission check
failed for all target processes.
On Linux, killpg
() is
implemented as a library function that makes the call
kill(-pgrp, sig).
This page is part of release 2.79 of the Linux man-pages
project. A
description of the project, and information about reporting
bugs, can be found at
http://www.kernel.org/doc/man-pages/.
Copyright (c) 1980, 1991 Regents of the University of California. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by the University of California, Berkeley and its contributors. 4. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. (#)killpg.2 6.5 (Berkeley) 3/10/91 Modified Fri Jul 23 21:55:01 1993 by Rik Faith <faithcs.unc.edu> Modified Tue Oct 22 08:11:14 EDT 1996 by Eric S. Raymond <esrthyrsus.com> Modified 2004-06-16 by Michael Kerrisk <mtk.manpagesgmail.com> Added notes on CAP_KILL Modified 2004-06-21 by aeb |