macosx/uptime.c

   1 #include <time.h>
   2 #include <errno.h>
   3 #include <sys/sysctl.h>
   4
   5 long uptime(void)
   6 {
   7     struct timeval boottime;
   8     size_t len = sizeof(boottime);
   9     int mib[2] = { CTL_KERN, KERN_BOOTTIME };
  10     if (sysctl(mib, 2, &boottime, &len, NULL, 0) < 0)
  11     {
  12         return -1L;
  13     }
  14     time_t bsec = boottime.tv_sec, csec = time(NULL);
  15
  16     return (long) difftime(csec, bsec);
  17 }