KILLPG(2)                           Linux Programmer's Manual                           KILLPG(2)



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():
           _BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED

DESCRIPTION
       killpg() sends the signal sig to the process group pgrp.  See signal(7) for a list of sig‐
       nals.

       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.

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  pro‐
              cesses.

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

NOTES
       There are various differences between the permission checking in BSD-type systems and Sys‐
       tem 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).

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

COLOPHON
       This  page  is  part of release 3.74 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 http://www.kernel.org/doc/man-pages/.



Linux                                       2010-09-20                                  KILLPG(2)