Socket客户端发送消息

我是套接字连接新手，我想发送一些命令，到套接字服务器，但我只能发送第一条消息，不能发送其他消息。

$fp = stream_socket_client("tcp://127.0.0.1:1000", $errno, $errstr, 30);
if (!$fp) {
    echo "$errstr ($errno)<br />'n";
} else {
    $cmd_1 = "hello";
    fwrite($fp, $cmd_1);
    while (!feof($fp)) {
        print_r(fgets($fp, 1024));
    }
    $cmd_2 = "second message";
    fwrite($fp, $cmd_2);
    while (!feof($fp)) {
        print_r(fgets($fp, 1024));
    }
    fclose($fp);
}

我如何发送像第一个$cmd_1这样的多条消息，并且取决于结果，我必须发送$cmd_2 ?

error_reporting(E_ALL);
/* Allow the script to hang around waiting for connections. */
set_time_limit(0);
/* Turn on implicit output flushing so we see what we're getting
 * as it comes in. */
ob_implicit_flush();
$address = '127.0.0.1';
$port = 1000;
if (($sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) === false) {
    echo "socket_create() failed: reason: " . socket_strerror(socket_last_error()) . "'n";
}
if (socket_bind($sock, $address, $port) === false) {
    echo "socket_bind() failed: reason: " . socket_strerror(socket_last_error($sock)) . "'n";
}
if (socket_listen($sock, 5) === false) {
    echo "socket_listen() failed: reason: " . socket_strerror(socket_last_error($sock)) . "'n";
}
do {
    if (($msgsock = socket_accept($sock)) === false) {
        echo "socket_accept() failed: reason: " . socket_strerror(socket_last_error($sock)) . "'n";
        break;
    }
    /* Send instructions. */
    $msg = "'nWelcome to the PHP Test Server. 'n" .
        "To quit, type 'quit'. To shut down the server type 'shutdown'.'n";
    socket_write($msgsock, $msg, strlen($msg));
    do {
        if (false === ($buf = socket_read($msgsock, 2048, PHP_NORMAL_READ))) {
            echo "socket_read() failed: reason: " . socket_strerror(socket_last_error($msgsock)) . "'n";
            break 2;
        }
        if (!$buf = trim($buf)) {
            continue;
        }
        if ($buf == 'quit') {
            break;
        }
        if ($buf == 'shutdown') {
            socket_close($msgsock);
            break 2;
        }
        $talkback = "PHP: You said '$buf'.'n";
        socket_write($msgsock, $talkback, strlen($talkback));
        echo "$buf'n";
    } while (true);
    socket_close($msgsock);
} while (true);
socket_close($sock);