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diff --git a/sysdeps/posix/sigwait.c b/sysdeps/posix/sigwait.c
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+/* sigwait - implementation of sigwait function from POSIX.1c.
+ Copyright (C) 1996 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+
+
+/* This is our dummy signal handler we use here. */
+static void ignore_signal (int sig);
+
+/* Place where to remember which signal we got. Please note that this
+ implementation cannot be used for the threaded libc. The
+ libpthread must provide an own version. */
+static int was_sig;
+
+
+int
+__sigwait (const sigset_t *set, int *sig)
+{
+ sigset_t tmp_mask;
+ struct sigaction saved[NSIG];
+ struct sigaction action;
+ int save_errno;
+ int this;
+
+ /* Prepare set. */
+ sigfillset (&tmp_mask);
+
+ /* Unblock all signals in the SET and register our nice handler. */
+ action.sa_handler = ignore_signal;
+ action.sa_flags = 0;
+ sigfillset (&action.sa_mask); /* Block all signals for handler. */
+
+ /* Make sure we recognize error conditions by setting WAS_SIG to a
+ value which does not describe a legal signal number. */
+ was_sig = -1;
+
+ for (this = 0; this < NSIG; ++this)
+ if (sigismember (set, this))
+ {
+ /* Unblock this signal. */
+ sigdelset (&tmp_mask, this);
+
+ /* Register temporary action handler. */
+ if (sigaction (this, &action, &saved[this]) != 0)
+ goto restore_handler;
+ }
+
+ /* Now we can wait for signals. */
+ sigsuspend (&tmp_mask);
+
+ restore_handler:
+ save_errno = errno;
+
+ while (--this >= 0)
+ if (sigismember (set, this))
+ /* We ignore errors here since we must restore all handlers. */
+ sigaction (this, &saved[this], NULL);
+
+ __set_errno (save_errno);
+
+ /* Store the result and return. */
+ *sig = was_sig;
+ return was_sig == -1 ? -1 : 0;
+}
+weak_alias (__sigwait, sigwait)
+
+
+static void
+ignore_signal (int sig)
+{
+ /* Remember the signal. */
+ was_sig = sig;
+}