DESCRIPTION

     Killpg sends the signal sig to the process group pgrp.   See
     sigaction(2)  for  a  list of signals.  If pgrp is 0, killpg
     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.

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.

     ESRCH
          No process can be found in the process group  specified
          by pgrp.

     ESRCH
          The process group was given as 0 but the  sending  pro-
          cess does not have a process group.

     EPERM
          The sending process is not the super-user  and  one  or
          more  of  the target processes has an effective user ID
          different from that of the sending process.

CONFORMING TO

     SVr4, 4.4BSD (The killpg function  call  first  appeared  in
     4.0BSD).

SEE ALSO

     kill(2), getpgrp(2), signal(2)