Documentation on stream_socket_server
stream_socket_server = Create an Internet or Unix domain server socket
Creates a stream or datagram socket on the specified local_socket.
This function only creates a socket, to begin accepting connections use stream_socket_accept().
Usage, params, and more on stream_socket_server
resource stream_socket_server ( string $local_socket
[, int &$errno
[, string &$errstr
[, int $flags
= STREAM_SERVER_BIND | STREAM_SERVER_LISTEN [, resource $context
]]]] )
local_socket
The type of socket created is determined by the transport specified using standard URL formatting: transport://target. For Internet Domain sockets (AF_INET
) such as TCP and UDP, the target portion of the remote_socket
parameter should consist of a hostname or IP address followed by a colon and a port number. For Unix domain sockets, the target portion should point to the socket file on the filesystem. Depending on the environment, Unix domain sockets may not be available. A list of available transports can be retrieved using stream_get_transports(). See List of Supported Socket Transports for a list of bulitin transports. errno
If the optional errno
and errstr
arguments are present they will be set to indicate the actual system level error that occurred in the system-level socket(), bind(), and listen() calls. If the value returned in errno
is 0 and the function returned FALSE
, it is an indication that the error occurred before the bind() call. This is most likely due to a problem initializing the socket. Note that the errno
and errstr
arguments will always be passed by reference. errstr
See errno
description. flags
A bitmask field which may be set to any combination of socket creation flags. Note: For UDP sockets, you must use STREAM_SERVER_BIND
as the flags
parameter. context
Returns the created stream, or FALSE
on error.
Notes and warnings on stream_socket_server
Basic example of how to use: stream_socket_server
Example #1 Using TCP server sockets
<?php
$socket = stream_socket_server("tcp://0.0.0.0:8000", $errno, $errstr);
if (!$socket) {
echo "$errstr ($errno)<br />\n";
} else {
while ($conn = stream_socket_accept($socket)) {
fwrite($conn, 'The local time is ' . date('n/j/Y g:i a') . "\n");
fclose($conn);
}
fclose($socket);
}
?>
The example below shows how to act as a time server which can respond to time queries as shown in an example on stream_socket_client().
Note: Most systems require root access to create a server socket on a port below 1024.
Example #2 Using UDP server sockets
<?php
$socket = stream_socket_server("udp://127.0.0.1:1113", $errno, $errstr, STREAM_SERVER_BIND);
if (!$socket) {
die("$errstr ($errno)");
}
do {
$pkt = stream_socket_recvfrom($socket, 1, 0, $peer);
echo "$peer\n";
stream_socket_sendto($socket, date("D M j H:i:s Y\r\n"), 0, $peer);
} while ($pkt !== false);
?>
Other code examples of stream_socket_server being used
In some specialized scenarios, you may want to create an AF_INET socket (UDP or TCP) but let the system select an unused port for you. This is a standard feature of internet sockets but it doesn't seem to be documented how to do this for the stream_socket_server function. It appears you can get this behavior by selecting zero for the port number, for example, my test below printed "127.0.0.1:4960".
<?php
$sock = stream_socket_server("udp://127.0.0.1:0");
$name = stream_socket_get_name($sock);
echo $name;
?>