usr/src/lib/libbc/libc/gen/common/clock.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1987 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"  /* from S5R2 1.1 */
  31
  32 /*LINTLIBRARY*/
  33
  34 #include <sys/types.h>
  35 #include <sys/times.h>
  36 #include <sys/param.h>  /* for HZ (clock frequency in Hz) */
  37 #define TIMES(B)        (B.tms_utime+B.tms_stime+B.tms_cutime+B.tms_cstime)
  38
  39 extern long times();
  40 static long first;
  41
  42 long
  43 clock()
  44 {
  45         struct tms buffer;
  46
  47         if (times(&buffer) == -1L)
  48                 return (0L);
  49         if (first == 0L)
  50                 first = TIMES(buffer);
  51         return ((TIMES(buffer) - first) * (1000000L/HZ));
  52 }