PHP socket communication mechanism example description and code_PHP tutorial

php socket communication mechanism example description and code

php tutorial socket communication mechanism example description and code

1. What is socket

What is socket? The so-called socket is also usually called "socket" ", used to describe the IP address and port, is the handle of a communication chain. Applications usually make requests to the network or respond to network requests through "sockets". To put it bluntly, it is a communication mechanism. It is similar to the telephone customer service departments of banks, telecommunications and other departments. When you call, a person will be allocated there to answer your questions. The customer service department is equivalent to the server side of the socket, and your side is equivalent to the client. Before the call ends with you, if someone is on It is impossible to talk to the person you are talking to because you are communicating with him. Of course, the telephone switchboard of the customer service department will not be duplicated.
I will give an example below to explain how socket works. If you are developing based on the application layer, you do not necessarily need to understand the principle, but it is better to know. There are php apis about sockets on the Internet. Just put it down and use it.

Second, socket server server.php
// Create server-side socket
$tcp = getprotobyname("tcp");
$socket = socket_create( af_inet, sock_stream, $tcp);
socket_bind($socket, '127.0.0.1', 10008); //Bind the port to be listened to
socket_listen($socket); //Listening port

//Initialize a data and communicate with the client
$buffer = "connect";
while (true) {
// Accept a socket connection
$connection = socket_accept($socket) ;
if(!$connection){
echo "connect fail";
}else{
echo "socket connectedn";
// Pass an information data to the client
if ($buffer != "") {
                                                                                                      echo "send data to clientn"; { )) {
                                                                                                                                                                                                                                                                         ;               }
}

socket_close($connection);
//Close the socket
printf("closed the socketn");
}
?>

Three, socket client client.php
// Establish the client's socket connection

$socket = socket_create(af_inet, sock_stream, sol_tcp);

$connection = socket_connect($socket, ' 127.0.0.1', 10008); //Connect to the server socket

while ($buffer = @socket_read($socket, 1024, php_normal_read)) {
//The server tells the client that its own Status
if (preg_match("/not connect/",$buffer)) {

echo "don`t connectn";

break;
} else {
//From the server Message
echo "buffer data: " . $buffer . "n";

echo "writing to socketn";
// Write the client's information into the channel and pass it to the server
if (!socket_write($socket, "some datan")) {
echo "Write failedn";
}
// After receiving the information at the server side, the response information given
While ($ buffer = socket_read ($ socket, 1024, php_normal_read)) {
Echo " sent to server: some datan response from server was:". $buffer. "n"; Fourth, a picture of the communication mechanism (automatically closing the socket regardless of the waiting time)

A brief explanation. Before explaining, I want to say why you need to use the php command to execute the server and Client, if you use fsockopen on the client side, accessing it on the browser will at least cause the connection to time out. Why is this? Because when you create a socket, it will constantly monitor whether the client wants to connect.

The establishment of socket communication requires two socket channels, one created by the server and one created by the client.

Line 1, the server creates a socket channel, puts the information in the cache, and waits for the client to connect.

Line 2, the client creates a socket channel and connects to the server to obtain server-side information for communication. Send the information to be transmitted to channel

Line 3. The server obtains the information from the client and tells the client that I have received the information. Send the information to be transmitted to the channel

Line 4, and the client obtains the confirmation information from the server

At this point, the communication is completely established. After the data transmission is completed, the server will disconnect the socket communication. The specific operations are as follows

1. Run the socket server


[root@blackghost zhangy]# /usr/local/php/bin/php -a /home/zhangy/www/ test2/server.php
interactive mode enabled
What kind of work has this done

a, listening to a 10008 port

[zhangy@blackghost ~]$ netstat -an |grep listen |grep 10008
tcp 0 0 127.0.0.1:10008 0.0.0.0:* listen

[zhangy@blackghost ~]$

b, send the information to the cache $buffer = "connect"; look at the code above

2, run the socket client

[root@blackghost zhangy]# /usr/local/php/bin/php -a /home/zhangy/www/test2/client.php
interactive mode enabled

buffer data: connect

writing to socket

sent to server: some data

response from server was:information received

3, Back to the server

[root@blackghost zhangy]# /usr/local/php/bin/php -a /home/zhangy/www/test2/server.php

interactive mode enabled

socket connected
send data to client

wrote to socket

buffer: some data

closed the socket

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TechArticlephp socket communication mechanism example description and code php tutorial socket communication mechanism example description and code 1, what is socket what is it socket The so-called socket is usually also called a socket and is used to describe...