sleep.c

   1 #define _POSIX_C_SOURCE 200809L
   2 #include <sys/time.h>
   3 #include <time.h>
   4 #include <stdlib.h>
   5
   6 int main(int argc, char** argv) {
   7         int i;
   8         char* end;
   9         int times;
  10         for(i = 1; i < argc; i++) {
  11                 double s = strtod(argv[i], &end);
  12                 switch(*end) {
  13                         case 'm':
  14                                 times = 60;
  15                                 break;
  16                         case 'h':
  17                                 times = 60 * 60;
  18                                 break;
  19                         case 'd':
  20                                 times = 60 * 60 * 24;
  21                                 break;
  22                         default:
  23                                 times = 1;
  24                 }
  25                 while(times--) {
  26                         long long sec = s;
  27                         long long ns = (s - (double) sec) * 1000000000.f;
  28                         nanosleep(&(struct timespec) { .tv_sec = sec, .tv_nsec = ns }, NULL);
  29                 }
  30         }
  31         return 0;
  32 }