apps/plugins/pdbox/PDa/src/s_watchdog.c

   1 /* Copyright (c) 1997-2000 Miller Puckette.
   2 * For information on usage and redistribution, and for a DISCLAIMER OF ALL
   3 * WARRANTIES, see the file, "LICENSE.txt," in this distribution.  */
   4
   5 /* This file is compiled into the separate program, "pd-watchdog," which
   6 tries to prevent Pd from locking up the processor if it's at realtime
   7 priority.  Linux only.  Invoked from s_inter.c. */
   8
   9 #include <sys/time.h>
  10 #include <sys/types.h>
  11 #include <unistd.h>
  12 #include <signal.h>
  13 #include <stdio.h>
  14
  15 int main(int argc, char **argv)
  16 {
  17     int happy = 1;
  18     while (1)
  19     {
  20         struct timeval timout;
  21         fd_set readset;
  22         if (happy)
  23         {
  24             timout.tv_sec = 5;
  25             timout.tv_usec = 0;
  26         }
  27         else
  28         {
  29             timout.tv_sec = 2;
  30             timout.tv_usec = 0;
  31         }
  32         FD_ZERO(&readset);
  33         FD_SET(0, &readset);
  34         select(1, &readset, 0, 0, &timout);
  35         if (FD_ISSET(0, &readset))
  36         {
  37             char buf[100];
  38             happy = 1;
  39             if (read(0, &buf, 100) <= 0)
  40                 return (0);
  41             else continue;
  42         }
  43         happy = 0;
  44         kill(getppid(), SIGHUP);
  45         fprintf(stderr, "watchdog: signaling pd...\n");
  46     }
  47 }
  48