commands/reboot/tinyhalt.c

   1 /*      tinyhalt 1.0 - small forerunner                 Author: Kees J. Bot
   2  *
   3  * Disk space on the root file system is a scarce resource.  This little
   4  * program sits in /sbin.  It normally calls the real halt/reboot, but if
   5  * that isn't available then it simply calls reboot().  Can't do any logging
   6  * of the event anyhow.
   7  */
   8 #define nil 0
   9 #include <sys/types.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <fcntl.h>
  13 #include <unistd.h>
  14 #include <signal.h>
  15
  16 int main(int argc, char **argv)
  17 {
  18         int flag;
  19         char *prog;
  20         char *reboot_code = "delay; boot";
  21
  22         /* Try to run the real McCoy. */
  23 #if __minix_vmd
  24         execv("/usr/sbin/halt", argv);
  25 #else
  26         execv("/usr/bin/halt", argv);
  27 #endif
  28
  29         if ((prog = strrchr(*argv,'/')) == nil) prog= argv[0]; else prog++;
  30
  31         sleep(1);       /* Not too fast. */
  32         signal(SIGHUP, SIG_IGN);
  33         signal(SIGTERM, SIG_IGN);
  34         kill(1, SIGTERM);
  35         kill(-1, SIGTERM);
  36         sleep(1);
  37
  38         reboot(strcmp(prog, "reboot") == 0 ? RBT_MONITOR : RBT_HALT,
  39                 reboot_code, strlen(reboot_code));
  40
  41         write(2, "reboot call failed\n", 19);
  42         return 1;
  43 }