1/* Copyright (C) 1991-2024 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 <https://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. */
24int
25__getpgid (pid_t pid)
26{
27 error_t err;
28 pid_t pgrp;
29
30 if (pid == 0)
31 {
32 /* Assume atomic word fetch and store, so don't lock _hurd_pid_lock. */
33 pgrp = _hurd_pgrp;
34 err = 0;
35 }
36 else
37 err = __USEPORT (PROC, __proc_getpgrp (port, pid, &pgrp));
38
39 return err ? __hurd_fail (err) : pgrp;
40}
41libc_hidden_def (__getpgid)
42weak_alias (__getpgid, getpgid)
43

source code of glibc/sysdeps/mach/hurd/getpgid.c