PHP与socket编程

//确保在连接客户端时不会超时
set_time_limit(0);
//设置IP和端口号
$address = "127.0.0.1";
$port    = 2046;

/**
 * 创建一个SOCKET
 * AF_INET=是ipv4 如果用ipv6，则参数为 AF_INET6
 * SOCK_STREAM为socket的tcp类型，如果是UDP则使用SOCK_DGRAM
 */
$sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP) or die_error();
//阻塞模式
socket_set_block($sock) or die_error();
//绑定到socket端口
$result = socket_bind($sock, $address, $port) or die_error();
//开始监听
$result = socket_listen($sock, 4) or die_error();
echo "OK\nBinding the socket on $address:$port ... ";
echo "OK\nNow ready to accept connections.\nListening on the socket ... \n";
do {
    // never stop the daemon
    //它接收连接请求并调用一个子连接Socket来处理客户端和服务器间的信息
    $msgsock = socket_accept($sock) or die_error();

    //读取客户端数据
    echo "Read client data \n";
    //socket_read函数会一直读取客户端数据,直到遇见\n,\t或者\0字符.PHP脚本把这写字符看做是输入的结束符.
    $buf = socket_read($msgsock, 8192);
    echo "Received msg: $buf  \n";

    //数据传送 向客户端写入返回结果
    $msg = "welcome \n";
    socket_write($msgsock, $msg, strlen($msg)) or die_error();
    //一旦输出被返回到客户端,父/子socket都应通过socket_close($msgsock)函数来终止
    socket_close($msgsock);
} while (true);
socket_close($sock);

/**
 * 展示错误
 * @return string
 */
function die_error(){
    $errorcode = socket_last_error();
    $errormsg = socket_strerror($errorcode);
    die("Couldn't create socket: [$errorcode] $errormsg" . PHP_EOL);
}

set_time_limit(0);

$host   = "127.0.0.1";
$port   = 2046;
// 创建一个Socket
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP) or die_error();

// 连接socket
$connection = socket_connect($socket, $host, $port) or die_error();
// 数据传送 向服务器发送消息
socket_write($socket, "hello socket") or die_error();
while ($buff = socket_read($socket, 1024, PHP_NORMAL_READ)) {
    echo ("Response was:" . $buff . "\n");
}
socket_close($socket);

/**
 * 展示错误
 * @return string
 */
function die_error(){
    $errorcode = socket_last_error();
    $errormsg = socket_strerror($errorcode);
    die("Couldn't create socket: [$errorcode] $errormsg" . PHP_EOL);
}

# server.php
$addr  = '127.0.0.1';
$port  = 80;
/**
 * 指定协议，绑定端口，添加引用两个错误信息提示参数
 * 这一步完成了sokect 绑定
 */
$server = stream_socket_server("tcp://$addr:$port", $errno, $errorMessage);

if ($server === false) {
    throw new UnexpectedValueException("Could not bind to socket: $errorMessage");
}

for (;;) {
    //它接收连接请求并调用一个子连接Socket来处理客户端和服务器间的信息
    $client = @stream_socket_accept($server);

    if ($client) {
        //从第一个参数的流中复制字节，将其作为第二个参数流,返回客户端请求内容
        stream_copy_to_stream($client, $client);
        //关闭客户端连接
        fclose($client);
    }
}

# client.php
//连接的主机的IP地址
//$addr = gethostbyname("www.example.com");
$addr = '127.0.0.1';
$port = 80;
//创建socket连接
$client = stream_socket_client("tcp://$addr:$port", $errno, $errorMessage);

if ($client === false) {
    throw new UnexpectedValueException("Failed to connect: $errorMessage");
}

//套接字连接由stream_socket_client是溪流，就像通过fopen打开文件
fwrite($client, "GET / HTTP/1.0\r\nHost: www.example.com\r\nAccept: */*\r\n\r\n");
//获取响应
echo stream_get_contents($client);
fclose($client);