c_cpp/etc/calc/have_gettime.c

   1 /*
   2  * have_gettime - determine if we have clock_gettime()
   3  *
   4  * Copyright (C) 1999  Landon Curt Noll
   5  *
   6  * Calc is open software; you can redistribute it and/or modify it under
   7  * the terms of the version 2.1 of the GNU Lesser General Public License
   8  * as published by the Free Software Foundation.
   9  *
  10  * Calc is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
  13  * Public License for more details.
  14  *
  15  * A copy of version 2.1 of the GNU Lesser General Public License is
  16  * distributed with calc under the filename COPYING-LGPL.  You should have
  17  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  18  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  *
  20  * @(#) $Revision: 30.1 $
  21  * @(#) $Id: have_gettime.c,v 30.1 2007/03/16 11:09:46 chongo Exp $
  22  * @(#) $Source: /usr/local/src/bin/calc/RCS/have_gettime.c,v $
  23  *
  24  * Under source code control:   1999/10/20 23:43:42
  25  * File existed as early as:    1999
  26  *
  27  * chongo <was here> /\oo/\     http://www.isthe.com/chongo/
  28  * Share and enjoy!  :-)        http://www.isthe.com/chongo/tech/comp/calc/
  29  */
  30
  31 /*
  32  * usage:
  33  *      have_gettime
  34  *
  35  * Not all systems have the clock_gettime() function, so this may not
  36  * compile on your system.
  37  *
  38  * This prog outputs several defines:
  39  *
  40  *      HAVE_GETTIME
  41  *              defined ==> use clock_gettime() for either CLOCK_SGI_CYCLE
  42  *                          and/or CLOCK_REALTIME
  43  *              undefined ==> clock_gettime() is not available for both
  44  *                            CLOCK_SGI_CYCLE and CLOCK_REALTIME
  45  */
  46
  47
  48 #include <time.h>
  49
  50 int
  51 main(void)
  52 {
  53 #if defined(HAVE_NO_GETTIME)
  54
  55         printf("#undef HAVE_GETTIME /* no */\n");
  56
  57 #else /* HAVE_NO_GETTIME */
  58
  59 # if defined(CLOCK_SGI_CYCLE)
  60
  61         struct timespec sgi_cycle;      /* SGI hardware clock */
  62         (void) clock_gettime(CLOCK_SGI_CYCLE, &sgi_cycle);
  63         printf("#define HAVE_GETTIME /* yes - w/CLOCK_SGI_CYCLE */\n");
  64
  65 # elif defined(CLOCK_REALTIME)
  66
  67         struct timespec realtime;       /* POSIX realtime clock */
  68         (void) clock_gettime(CLOCK_REALTIME, &realtime);
  69         printf("#define HAVE_GETTIME /* yes - CLOCK_REALTIME only */\n");
  70
  71 # else
  72
  73         printf("#undef HAVE_GETTIME /* no - no SGI_CYCLE and no REALTIME */\n");
  74
  75 # endif /* CLOCK_REALTIME */
  76
  77 #endif /* HAVE_NO_GETTIME */
  78         /* exit(0); */
  79         return 0;
  80 }