sysdeps/posix/pause.c

   1 /* pause -- suspend the process until a signal arrives.  POSIX.1 version.
   2    Copyright (C) 2003-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <signal.h>
  20 #include <unistd.h>
  21 #include <sysdep-cancel.h>
  22
  23 /* Suspend the process until a signal arrives.
  24    This always returns -1 and sets errno to EINTR.  */
  25
  26 int
  27 __libc_pause (void)
  28 {
  29   sigset_t set;
  30
  31   __sigemptyset (&set);
  32   __sigprocmask (SIG_BLOCK, NULL, &set);
  33
  34   /* pause is a cancellation point, but so is sigsuspend.
  35      So no need for anything special here.  */
  36
  37   return __sigsuspend (&set);
  38 }
  39 weak_alias (__libc_pause, pause)
  40
  41 LIBC_CANCEL_HANDLED ();         /* sigsuspend handles our cancellation.  */
  42
  43 #ifndef NO_CANCELLATION
  44 # include <not-cancel.h>
  45
  46 int
  47 __pause_nocancel (void)
  48 {
  49   sigset_t set;
  50
  51   __sigemptyset (&set);
  52   __sigprocmask (SIG_BLOCK, NULL, &set);
  53
  54   return sigsuspend_not_cancel (&set);
  55 }
  56 #endif