killpg(3) Library Functions Manual killpg(3)
NAME
killpg - send signal to a process group
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <signal.h>
int killpg(int pgrp, int sig);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
killpg():
_XOPEN_SOURCE >= 500
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE
DESCRIPTION
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 the permissions required to send a signal to another process, see
kill(2).
RETURN VALUE
On success, zero is returned. On error, -1 is returned, and errno is
set to indicate the error.
ERRORS
EINVAL sig is not a valid signal number.
EPERM The process does not have permission to send the signal to any
of the target processes. For the required permissions, see
kill(2).
ESRCH No process can be found in the process group specified by pgrp.
ESRCH The process group was given as 0 but the sending process does
not have a process group.
VERSIONS
There are various differences between the permission checking in BSD-
type systems and System V-type systems. See the POSIX rationale for
kill(3p). 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.
C library/kernel differences
On Linux, killpg() is implemented as a library function that makes the
call kill(-pgrp, sig).
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001, SVr4, 4.4BSD (first appeared in 4BSD).
SEE ALSO
getpgrp(2), kill(2), signal(2), capabilities(7), credentials(7)
Linux man-pages 6.7 2023-10-31 killpg(3)
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