sysdeps/posix/pause.c

   1 /* pause -- suspend the process until a signal arrives.  POSIX.1 version.
   2    Copyright (C) 2003, 2006 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <signal.h>
  21 #include <unistd.h>
  22 #include <sysdep-cancel.h>
  23
  24 /* Suspend the process until a signal arrives.
  25    This always returns -1 and sets errno to EINTR.  */
  26
  27 int
  28 __libc_pause (void)
  29 {
  30   sigset_t set;
  31
  32   __sigemptyset (&set);
  33   __sigprocmask (SIG_BLOCK, NULL, &set);
  34
  35   /* pause is a cancellation point, but so is sigsuspend.
  36      So no need for anything special here.  */
  37
  38   return __sigsuspend (&set);
  39 }
  40 weak_alias (__libc_pause, pause)
  41
  42 LIBC_CANCEL_HANDLED ();         /* sigsuspend handles our cancellation.  */
  43
  44 #ifndef NO_CANCELLATION
  45 # include <not-cancel.h>
  46
  47 int
  48 __pause_nocancel (void)
  49 {
  50   sigset_t set;
  51
  52   __sigemptyset (&set);
  53   __sigprocmask (SIG_BLOCK, NULL, &set);
  54
  55   return sigsuspend_not_cancel (&set);
  56 }
  57 #endif