xv6-lab/user/pingpong.c
2023-01-05 17:03:50 +08:00

27 lines
843 B
C

#include "kernel/types.h"
#include "user/user.h"
int main(int argc, char** argv) {
int p[2]; // hell, read from p[0] and write to p[1] no matter in pa/ch
if (pipe(p) == -1) exit(1);
uint8 senddata[] = {0xAC};
uint8 recvdata[] = {0};
int pid = fork();
if (pid == 0) {
// child
if (read(p[0], recvdata, 1) != 1) printf("error child read\n");
close(p[0]);
printf("%d: received ping\n", getpid());
if (write(p[1], senddata, 1) != 1) printf("error child write\n");
close(p[1]);
exit(0);
}
else {
if (write(p[1], senddata, 1) != 1) printf("error parent write\n");
close(p[1]);
if (read(p[0], recvdata, 1) != 1) printf("error parent read\n");
printf("%d: received pong\n", getpid());
close(p[0]);
exit(0);
}
}