code.delx.au - gnu-emacs/blob - lib-src/wakeup.c

   1 /* Program to produce output at regular intervals.  */
   2
   3 #include <stdio.h>
   4 #include <time.h>
   5 #include <sys/types.h>
   6 #include <sys/time.h>
   7
   8 struct tm *localtime ();
   9
  10 main (argc, argv)
  11      int argc;
  12      char **argv;
  13 {
  14   int period = 60;
  15   time_t when;
  16   struct tm *tp;
  17
  18   if (argc > 1)
  19     period = atoi (argv[1]);
  20
  21   while (1)
  22     {
  23       /* Make sure wakeup stops when Emacs goes away.  */
  24       if (getppid () == 1)
  25         exit (0);
  26       printf ("Wake up!\n");
  27       fflush (stdout);
  28       /* If using a period of 60, produce the output when the minute
  29          changes. */
  30       if (period == 60)
  31         {
  32           time (&when);
  33           tp = localtime (&when);
  34           sleep (60 - tp->tm_sec);
  35         }
  36       else
  37         sleep (period);
  38     }
  39 }