// RUN: %clangxx -O0 -g %s -o %t && %run %t
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
int main(void) {
int child;
int fd, sfd;
socklen_t len;
struct sockaddr_in server = {}, client = {};
sigset_t set;
child = fork();
if (child == 0) {
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd == -1)
_exit(1);
server.sin_family = AF_INET;
server.sin_addr.s_addr = INADDR_ANY;
server.sin_port = htons(2222);
if (connect(fd, (struct sockaddr *)&server, sizeof(server)) == -1)
_exit(1);
close(fd);
_exit(0);
}
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd == -1) {
kill(child, SIGKILL);
wait(NULL);
exit(1);
}
server.sin_family = AF_INET;
server.sin_addr.s_addr = INADDR_ANY;
server.sin_port = htons(2222);
if (bind(fd, (const struct sockaddr *)&server, sizeof(server)) == -1) {
kill(child, SIGKILL);
wait(NULL);
exit(1);
}
listen(fd, 3);
if (sigemptyset(&set) == -1) {
kill(child, SIGKILL);
wait(NULL);
exit(1);
}
len = sizeof(client);
sfd = paccept(fd, (struct sockaddr *)&client, &len, &set, SOCK_NONBLOCK);
if (sfd == -1) {
kill(child, SIGKILL);
wait(NULL);
exit(1);
}
wait(NULL);
close(sfd);
close(fd);
return 0;
}