sysdeps/mach/hurd/getpgid.c

   1 /* Copyright (C) 1991-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <unistd.h>
  20 #include <hurd.h>
  21 #include <hurd/port.h>
  22
  23 /* Get the process group ID of process PID.  */
  24 int
  25 __getpgid (pid)
  26      pid_t pid;
  27 {
  28   error_t err;
  29   pid_t pgrp;
  30
  31   if (pid == 0)
  32     {
  33       /* Assume atomic word fetch and store, so don't lock _hurd_pid_lock.  */
  34       pgrp = _hurd_pgrp;
  35       err = 0;
  36     }
  37   else
  38     err = __USEPORT (PROC, __proc_getpgrp (port, pid, &pgrp));
  39
  40   return err ? __hurd_fail (err) : pgrp;
  41 }
  42 libc_hidden_def (__getpgid)
  43 weak_alias (__getpgid, getpgid)