ping和ttl的iOS超时

Question

我想用超时和TTL进行ping.我使用Apple的代码("Simple Ping").我读到它 "iOS ping with timeout".我改变代码:

CFSocketNativeHandle sock = CFSocketGetNative(self->_socket);
struct timeval tv;
tv.tv_sec  = 0;
tv.tv_usec = 100000; // 0.1 sec
setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (void *)&tv, sizeof(tv));

bytesSent = sendto(
    sock,
    [packet bytes],
    [packet length], 
    0, 
    (struct sockaddr *) [self.hostAddress bytes], 
    (socklen_t) [self.hostAddress length]
);

但我不明白我应该把代码放在哪里,以显示我接收数据包的超时.此外,我需要使用TTL(生存时间)信息进行ping操作.我想根据这种模式获取信息:icmp_seq=count from=ip_address ttl=value_of_ttl time=value_of_replytime_ms

Answer 1

您始终可以对接收设置一些限制时间：

        tv.tv_sec = 0;
        tv.tv_usec = 10000;
        setsockopt(recv_sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv,sizeof(struct   timeval));