#include #include void sleepy(int pid) { int i, time = 100; for (i = 0; i < 10; i ++) { sleep(time); cprintf("sleep %d x %d slices.\n", i + 1, time); } exit(0); } int main(void) { unsigned int time = gettime_msec(); int pid1, exit_code; if ((pid1 = fork()) == 0) { sleepy(pid1); } assert(waitpid(pid1, &exit_code) == 0 && exit_code == 0); cprintf("use %04d msecs.\n", gettime_msec() - time); cprintf("sleep pass.\n"); return 0; }