<?php
/*文件名：socket_server.php*/
// 设置一些基本的变量
$host="127.0.0.1";//Socket运行的服务器的IP地址
$port=1234;//Socket运行的服务器的端口，端口取值为1到65535之间的数字，前提是这个端口未被使用
// 设置超时时间，这里设置为永不超时，确保PHP在等待客户端连接时不会超时。
set_time_limit(0);
// 创建一个Socket，返回一个Socket句柄
$socket=socket_create(AF_INET,SOCK_STREAM,0) or die("Could not create socket\n");
//绑定Socket到指定的地址和端口
$result=socket_bind($socket,$host,$port) or die("Could not bind to socket\n");
// 开始监听外部连接
$result=socket_listen($socket,3) or die("Could not set up socket listener\n");
/******到这里，服务器除了等待来自客户端的连接请求外基本上什么也不做******/
// 另一个Socket来处理服务端与客户端的通信
$spawn=socket_accept($socket) or die("Could not accept incoming connection\n");
// 读取客户端的输入，当一个连接被建立后,服务器就会等待客户端发送一些输入信息,这些信息可以由socket_read()函数来获得,并把它赋值给PHP的$input变量
$input=socket_read($spawn,1024) or die("Could not read input\n");
//socker_read的第二个参数用以指定读入的字节数，你可以通过它来限制从客户端获取数据的大小
// 下面这不就不解释了，不知道的自己面壁去
$input=trim($input);
//处理客户端输入并返回结果，当客户端发来数据信息后，信息输出就要靠socket_write()函数来完成
$output=strrev($input) ."\n";//反转字符串，这里仅仅是为了更好的区分两条信息
socket_write($spawn,$output,strlen($output)) or die("Could not write output\n");
// 关闭sockets
socket_close($spawn);
socket_close($socket);

<?php
$commonProtocol = getprotobyname("tcp");
$socket = socket_create(AF_INET, SOCK_STREAM, $commonProtocol);
socket_bind($socket, 'localhost', 1337); //socket_bind() 把socket绑定在一个IP地址和端口上
socket_listen($socket);
$buffer = "NO DATA";
while(true) {
 // Accept any connections coming in on this socket
 $connection = socket_accept($socket);//socket_accept() 接受一个Socket连接
 printf("Socket connected\r\n");
 // Check to see if there is anything in the buffer
 if($buffer != ""){
 printf("Something is in the buffer...sending data...\r\n");
 socket_write($connection, $buffer . "\r\n"); //socket_write() 写数据到socket缓存
 printf("Wrote to socket\r\n");
 }else {
 printf("No Data in the buffer\r\n");
 }
 // Get the input
 while($data = socket_read($connection, 1024, PHP_NORMAL_READ)){//socket_read() 读取指定长度的数据
 $buffer = $data;
 socket_write($connection, "Information Received\r\n");
 printf("Buffer: " . $buffer . "\r\n");
 }
 socket_close($connection); //socket_close() 关闭一个socket资源
 printf("Closed the socket\r\n\r\n");
}

<?php
// Create the socket and connect
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
$connection = socket_connect($socket,'localhost', 1337);
while($buffer = socket_read($socket, 1024, PHP_NORMAL_READ)) {
 if($buffer == "NO DATA") {
 echo("<p>NO DATA</p>");
 break;
 }else{
 // Do something with the data in the buffer
 echo("<p>Buffer Data: " . $buffer . "</p>");
 }
}
echo("<p>Writing to Socket</p>");
// Write some test data to our socket
if(!socket_write($socket, "SOME DATA\r\n")){
 echo("<p>Write failed</p>");
}
// Read any response from the socket phpernote.com
while($buffer = socket_read($socket, 1024, PHP_NORMAL_READ)){
 echo("<p>Data sent was: SOME DATA<br> Response was:" . $buffer . "</p>");
}
echo("<p>Done Reading from Socket</p>");