about summary refs log tree commit diff
path: root/sysdeps/unix/bsd/alarm.c
diff options
context:
space:
mode:
authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /sysdeps/unix/bsd/alarm.c
downloadglibc-28f540f45bbacd939bfd07f213bcad2bf730b1bf.tar.gz
glibc-28f540f45bbacd939bfd07f213bcad2bf730b1bf.tar.xz
glibc-28f540f45bbacd939bfd07f213bcad2bf730b1bf.zip
initial import
Diffstat (limited to 'sysdeps/unix/bsd/alarm.c')
-rw-r--r--sysdeps/unix/bsd/alarm.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/sysdeps/unix/bsd/alarm.c b/sysdeps/unix/bsd/alarm.c
new file mode 100644
index 0000000000..7743256a09
--- /dev/null
+++ b/sysdeps/unix/bsd/alarm.c
@@ -0,0 +1,43 @@
+/* Copyright (C) 1991, 1992, 1994 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+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., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+/* Schedule an alarm.  In SECONDS seconds, the process will get a SIGALRM.
+   If SECONDS is zero, any currently scheduled alarm will be cancelled.
+   The function returns the number of seconds remaining until the last
+   alarm scheduled would have signaled, or zero if there wasn't one.
+   There is no return value to indicate an error, but you can set `errno'
+   to 0 and check its value after calling `alarm', and this might tell you.
+   The signal may come late due to processor scheduling.  */
+unsigned int
+DEFUN(alarm, (seconds), unsigned int seconds)
+{
+  struct itimerval old, new;
+
+  new.it_interval.tv_usec = 0;
+  new.it_interval.tv_sec = 0;
+  new.it_value.tv_usec = 0;
+  new.it_value.tv_sec = (long int) seconds;
+  if (__setitimer(ITIMER_REAL, &new, &old) < 0)
+    return 0;
+
+  return (old.it_value.tv_sec + (old.it_value.tv_usec + 999999) / 1000000);
+}