1/* Copyright (C) 1993-2022 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/id.h>
22
23/* Get the real group ID of the calling process. */
24gid_t
25__getgid (void)
26{
27 error_t err;
28 gid_t gid;
29
30retry:
31 HURD_CRITICAL_BEGIN;
32 __mutex_lock (&_hurd_id.lock);
33
34 if (err = _hurd_check_ids ())
35 {
36 errno = err;
37 gid = -1;
38 }
39 else if (_hurd_id.aux.ngids >= 1)
40 gid = _hurd_id.aux.gids[0];
41 else
42 {
43 /* We do not even have a real gid. */
44 errno = EGRATUITOUS;
45 gid = -1;
46 }
47
48 __mutex_unlock (&_hurd_id.lock);
49 HURD_CRITICAL_END;
50 if (gid == -1 && errno == EINTR)
51 /* Got a signal while inside an RPC of the critical section, retry again */
52 goto retry;
53
54 return gid;
55}
56
57weak_alias (__getgid, getgid)
58

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