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/*
* Copyright (c) 1983, 1993, 2001
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "hertz.h"
int
hertz ()
{
#ifdef HERTZ
return HERTZ;
#else /* ! defined (HERTZ) */
#ifdef HAVE_SETITIMER
struct itimerval tim;
tim.it_interval.tv_sec = 0;
tim.it_interval.tv_usec = 1;
tim.it_value.tv_sec = 0;
tim.it_value.tv_usec = 0;
setitimer (ITIMER_REAL, &tim, 0);
setitimer (ITIMER_REAL, 0, &tim);
if (tim.it_interval.tv_usec >= 2)
{
return 1000000 / tim.it_interval.tv_usec;
}
#endif /* ! defined (HAVE_SETITIMER) */
#if defined (HAVE_SYSCONF) && defined (_SC_CLK_TCK)
return sysconf (_SC_CLK_TCK);
#else /* ! defined (HAVE_SYSCONF) || ! defined (_SC_CLK_TCK) */
#ifdef __MSDOS__
return 18;
#else /* ! defined (__MSDOS__) */
return HZ_WRONG;
#endif /* ! defined (__MSDOS__) */
#endif /* ! defined (HAVE_SYSCONF) || ! defined (_SC_CLK_TCK) */
#endif /* ! defined (HERTZ) */
}
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