1 /* Copyright (C) 1991-2021 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. */ 24 int __getpgid(pid_t pid)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 } 41 libc_hidden_def (__getpgid) 42 weak_alias (__getpgid, getpgid) 43