root/user/testbin/guzzle/guzzle.c

DEFINITIONS

1. main

   1 /*
   2  * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
   3  *      The President and Fellows of Harvard College.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  30 /*
  31  * guzzle: Sit in the background in a long loop and display 
  32  * characters on the console occasionally.
  33  *
  34  * This is intended to help with scheduler testing.
  35  */
  37 #include <stdio.h>
  38 #include <unistd.h>
  40 #define  TOP     1<<25  /* real long loop */
  42 /* This program is a ridiculous, compute-bound program */
  43 /* We should schedule this at low priorities. */
  45 int
main(int argc, char *argv[])
  47 {
  48         volatile int i;
  49         int ch = '+';
  51         if (argc == 2) {
ch = argv[1][0];
  53         }
  55         for (i=0; i<TOP; i++) { /* tight loop */
  56                                 /* that eats up cycles */
  57                 if ( (i%10000) == 0) {
putchar(ch);
  59                 }
  60         }
  61         return 0;
  62 }