test/sysperf/pipe1.c

   1 /*
   2  * pipe1.c
   3  *
   4  * $DragonFly: src/test/sysperf/pipe1.c,v 1.1 2003/08/12 02:29:44 dillon Exp $
   5  */
   6
   7 #include "blib.h"
   8
   9 int
  10 main(int ac, char **av)
  11 {
  12     long long count = 0;
  13     long long max;
  14     char c;
  15     int j;
  16     int fds[2];
  17
  18     printf("tests full duplex pipe 1write,2read,2write,1read loop\n");
  19     if (pipe(fds)) {
  20         perror("pipe");
  21         exit(1);
  22     }
  23     if (fork() == 0) {
  24         /*
  25          * child process
  26          */
  27         close(fds[0]);
  28         while (read(fds[1], &c, 1) == 1) {
  29             write(fds[1], &c, 1);
  30         }
  31         _exit(0);
  32     } else {
  33         /*
  34          * parent process.
  35          */
  36         close(fds[1]);
  37         write(fds[0], &c, 1);   /* prime the caches */
  38         read(fds[0], &c, 1);
  39         start_timing();
  40         for (j = 0; j < 100000; ++j) {
  41             write(fds[0], &c, 1);
  42             if (read(fds[0], &c, 1) != 1) {
  43                 fprintf(stderr, "broken pipe during test\n");
  44                 exit(1);
  45             }
  46         }
  47         stop_timing(j, "full duplex pipe / 1char:");
  48         close(fds[0]);
  49         while(wait(NULL) >= 0);
  50     }
  51     return(0);
  52 }
  53