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/* Copyright (C) 1999, 2000, 2001 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., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <time.h>
#include <unistd.h>
#ifndef EXTRA_CLOCK_CASES
# define EXTRA_CLOCK_CASES
#endif
/* Get resolution of clock. */
int
clock_getres (clockid_t clock_id, struct timespec *res)
{
int retval = -1;
switch (clock_id)
{
case CLOCK_REALTIME:
{
long int clk_tck = sysconf (_SC_CLK_TCK);
if (__builtin_expect (clk_tck != -1, 1))
{
/* This implementation assumes that the realtime clock has a
resolution higher than 1 second. This is the case for any
reasonable implementation. */
res->tv_sec = 0;
res->tv_nsec = 1000000000 / clk_tck;
retval = 0;
}
}
break;
EXTRA_CLOCK_CASES
default:
__set_errno (EINVAL);
break;
}
return retval;
}
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