coreutils/lib/settime.c

75 lines
1.7 KiB
C

/* settime -- set the system clock
Copyright (C) 2002, 2004 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by Paul Eggert. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "timespec.h"
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <errno.h>
/* Some systems don't have ENOSYS. */
#ifndef ENOSYS
# ifdef ENOTSUP
# define ENOSYS ENOTSUP
# else
/* Some systems don't have ENOTSUP either. */
# define ENOSYS EINVAL
# endif
#endif
/* Set the system time. */
int
settime (struct timespec const *ts)
{
#if defined CLOCK_REALTIME && HAVE_CLOCK_SETTIME
{
int r = clock_settime (CLOCK_REALTIME, ts);
if (r == 0 || errno == EPERM)
return r;
}
#endif
#if HAVE_SETTIMEOFDAY
{
struct timeval tv;
int r;
tv.tv_sec = ts->tv_sec;
tv.tv_usec = ts->tv_nsec / 1000;
r = settimeofday (&tv, 0);
if (r == 0 || errno == EPERM)
return r;
}
#endif
#if HAVE_STIME
return stime (&ts->tv_sec);
#else
errno = ENOSYS;
return -1;
#endif
}