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Diffstat (limited to 'sysdeps/unix/bsd/alarm.c')
-rw-r--r-- | sysdeps/unix/bsd/alarm.c | 43 |
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); +} |