text: /* Return frequency of ticks reported by profil.  Generic version. */
  /*-
   * Copyright (c) 1983, 1992, 1993
   *	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.
   * 4. 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 <sys/types.h>
  #include <sys/time.h>
  #include <libc-internal.h>
  
  int
  __profile_frequency (void)
  {
    /*
     * Discover the tick frequency of the machine if something goes wrong,
     * we return 0, an impossible hertz.
     */
    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 0;
    return (1000000 / tim.it_interval.tv_usec);
  }
  