os_kernel_lab/labcodes/lab8/user/spin.c
2013-09-17 22:21:48 +08:00

30 lines
602 B
C

#include <stdio.h>
#include <ulib.h>
int
main(void) {
int pid, ret;
cprintf("I am the parent. Forking the child...\n");
if ((pid = fork()) == 0) {
cprintf("I am the child. spinning ...\n");
while (1);
}
cprintf("I am the parent. Running the child...\n");
yield();
yield();
yield();
cprintf("I am the parent. Killing the child...\n");
assert((ret = kill(pid)) == 0);
cprintf("kill returns %d\n", ret);
assert((ret = waitpid(pid, NULL)) == 0);
cprintf("wait returns %d\n", ret);
cprintf("spin may pass.\n");
return 0;
}