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killpg(3)


NAME

   killpg - send signal to a process group

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 versions <= 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 appropriately.

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.

CONFORMING TO

   POSIX.1-2001,  POSIX.1-2008,  SVr4,  4.4BSD (killpg() first appeared in
   4BSD).

NOTES

   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.

   C library/kernel differences
   On Linux, killpg() is implemented as a library function that makes  the
   call kill(-pgrp, sig).

SEE ALSO

   getpgrp(2), kill(2), signal(2), capabilities(7), credentials(7)

COLOPHON

   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at
   https://www.kernel.org/doc/man-pages/.



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