Streams
PHP Manual

stream_socket_pair

(PHP 5 >= 5.1.0)

stream_socket_pair — Creates a pair of connected, indistinguishable socket streams

Description

array stream_socket_pair ( int $domain , int $type , int $protocol )

stream_socket_pair() creates a pair of connected, indistinguishable socket streams. This function is commonly used in IPC (Inter-Process Communication).

Parameters

domain

The protocol family to be used: STREAM_PF_INET, STREAM_PF_INET6 or STREAM_PF_UNIX

type

The type of communication to be used: STREAM_SOCK_DGRAM, STREAM_SOCK_RAW, STREAM_SOCK_RDM, STREAM_SOCK_SEQPACKET or STREAM_SOCK_STREAM

protocol

The protocol to be used: STREAM_IPPROTO_ICMP, STREAM_IPPROTO_IP, STREAM_IPPROTO_RAW, STREAM_IPPROTO_TCP or STREAM_IPPROTO_UDP

Note: Please consult the Streams constant list for further details on each constant.

Return Values

Returns an array with the two socket resources on success, or FALSE on failure.

Examples

Example#1 A stream_socket_pair() example

This example shows the basic usage of stream_socket_pair() in Inter-Process Comunication.

<?php

$sockets 
stream_socket_pair(STREAM_PF_UNIXSTREAM_SOCK_STREAMSTREAM_IPPROTO_IP);
$pid     pcntl_fork();

if (
$pid == -1) {
     die(
'could not fork');

} else if (
$pid) {
     
/* parent */
    
fclose($sockets[0]);

    
fwrite($sockets[1], "child PID: $pid\n");
    echo 
fgets($sockets[1]);

    
fclose($sockets[1]);

} else {
    
/* child */
    
fclose($sockets[1]);

    
fwrite($sockets[0], "message from child\n");
    echo 
fgets($sockets[0]);

    
fclose($sockets[0]);
}

?>

The above example will output something similar to:

child PID: 1378 message from child


Streams
PHP Manual