stream_socket_pair
(PHP 5 >= 5.1.0)
stream_socket_pair — Creates a pair of connected, indistinguishable socket streams
Description
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_UNIX, STREAM_SOCK_STREAM, STREAM_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