socket_create_pair
(PHP 4 >= 4.1.0, PHP 5, PHP 7)
socket_create_pair — Creates a pair of indistinguishable sockets and stores them in an array
Description
socket_create_pair ( int $domain , int $type , int $protocol , array &$fd ) : bool
socket_create_pair() creates two connected and indistinguishable sockets, and stores them in fd. This function is commonly used in IPC (InterProcess Communication).
Parameters
-
domain -
The
domainparameter specifies the protocol family to be used by the socket. See socket_create() for the full list. -
type -
The
typeparameter selects the type of communication to be used by the socket. See socket_create() for the full list. -
protocol -
The
protocolparameter sets the specific protocol within the specifieddomainto be used when communicating on the returned socket. The proper value can be retrieved by name by using getprotobyname(). If the desired protocol is TCP, or UDP the corresponding constantsSOL_TCP, andSOL_UDPcan also be used.See socket_create() for the full list of supported protocols.
-
fd -
Reference to an array in which the two socket resources will be inserted.
Return Values
Returns true on success or false on failure.
Examples
Example #1 socket_create_pair() example
<?php
$sockets = array();
/* On Windows we need to use AF_INET */
$domain = (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN' ? AF_INET : AF_UNIX);
/* Setup socket pair */
if (socket_create_pair($domain, SOCK_STREAM, 0, $sockets) === false) {
echo "socket_create_pair failed. Reason: ".socket_strerror(socket_last_error());
}
/* Send and Receive Data */
if (socket_write($sockets[0], "ABCdef123\n", strlen("ABCdef123\n")) === false) {
echo "socket_write() failed. Reason: ".socket_strerror(socket_last_error($sockets[0]));
}
if (($data = socket_read($sockets[1], strlen("ABCdef123\n"), PHP_BINARY_READ)) === false) {
echo "socket_read() failed. Reason: ".socket_strerror(socket_last_error($sockets[1]));
}
var_dump($data);
/* Close sockets */
socket_close($sockets[0]);
socket_close($sockets[1]);
?> Example #2 socket_create_pair() IPC example
<?php
$ary = array();
$strone = 'Message From Parent.';
$strtwo = 'Message From Child.';
if (socket_create_pair(AF_UNIX, SOCK_STREAM, 0, $ary) === false) {
echo "socket_create_pair() failed. Reason: ".socket_strerror(socket_last_error());
}
$pid = pcntl_fork();
if ($pid == -1) {
echo 'Could not fork Process.';
} elseif ($pid) {
/*parent*/
socket_close($ary[0]);
if (socket_write($ary[1], $strone, strlen($strone)) === false) {
echo "socket_write() failed. Reason: ".socket_strerror(socket_last_error($ary[1]));
}
if (socket_read($ary[1], strlen($strtwo), PHP_BINARY_READ) == $strtwo) {
echo "Received $strtwo\n";
}
socket_close($ary[1]);
} else {
/*child*/
socket_close($ary[1]);
if (socket_write($ary[0], $strtwo, strlen($strtwo)) === false) {
echo "socket_write() failed. Reason: ".socket_strerror(socket_last_error($ary[0]));
}
if (socket_read($ary[0], strlen($strone), PHP_BINARY_READ) == $strone) {
echo "Received $strone\n";
}
socket_close($ary[0]);
}
?> See Also
- socket_create() - Create a socket (endpoint for communication)
- socket_create_listen() - Opens a socket on port to accept connections
- socket_bind() - Binds a name to a socket
- socket_listen() - Listens for a connection on a socket
- socket_last_error() - Returns the last error on the socket
- socket_strerror() - Return a string describing a socket error
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.socket-create-pair.php