lib-src/wakeup.c

   1 /* Program to produce output at regular intervals.  */
   2
   3 #include <stdio.h>
   4 #include <time.h>
   5
   6 struct tm *localtime ();
   7
   8 main (argc, argv)
   9      int argc;
  10      char **argv;
  11 {
  12   int period = 60;
  13   time_t when;
  14   struct tm *tp;
  15
  16   if (argc > 1)
  17     period = atoi (argv[1]);
  18
  19   while (1)
  20     {
  21       /* Make sure wakeup stops when Emacs goes away.  */
  22       if (getppid () == 1)
  23         exit (0);
  24       printf ("Wake up!\n");
  25       fflush (stdout);
  26       /* If using a period of 60, produce the output when the minute
  27          changes. */
  28       if (period == 60)
  29         {
  30           time (&when);
  31           tp = localtime (&when);
  32           sleep (60 - tp->tm_sec);
  33         }
  34       else
  35         sleep (period);
  36     }
  37 }