If you want to know the remote address ( ip address ) and the port of an incoming connection that has been accepted with socket_accept(), you can use socket_getpeername()
socket_accept
(PHP 4 >= 4.0.7, PHP 5)
socket_accept — Accepte une connexion sur une socket
Description
Une fois que la socket socket a été créée avec la fonction socket_create(), liée à un nom avec la fonction socket_bind(), et mise en attente de connexion avec la fonction socket_listen(), socket_accept() va accepter les connexions sur cette socket. Une fois qu'une connexion est faite, une nouvelle ressource de socket est retournée. Elle peut être utilisée pour les communications. S'il y a plusieurs connexions en attente, la première sera utilisée. S'il n'y a pas de connexion en attente, socket_accept() se bloquera jusqu'à ce qu'une connexion se présente. Si socket a été rendue non-bloquante, grâce à socket_set_blocking() ou socket_set_nonblock(), FALSE sera retourné.
La ressource de socket retournée par socket_accept() ne doit pas être utilisée pour accepter de nouvelles connexions. La socket originale socket , qui est en attente, reste ouverte et peut être réutilisée.
Valeurs de retour
Retourne une nouvelle ressource de socket en cas de succès ou FALSE en cas d'erreur. Le code d'erreur généré peut être obtenu en appelant la fonction socket_last_error(). Ce code d'erreur peut être passé à la fonction socket_strerror() pour obtenir un message d'erreur, humainement lisible.
socket_accept
10-May-2008 01:32
18-Apr-2008 06:01
If you want to have multiple clients on a server you will have to use non blocking.
<?php
$clients = array();
$socket = socket_create(AF_INET,SOCK_STREAM,SOL_TCP);
socket_bind($socket,'127.0.0.1',$port);
socket_listen($socket);
socket_set_nonblock($socket);
while(true)
{
if(($newc = socket_accept($socket)) !== false)
{
echo "Client $newc has connected\n";
$clients[] = $newc;
}
}
?>
29-Jan-2008 01:35
If you want to make a daemon process that forks on each client connection, you'll find out that there's a bug in PHP. The child processes send SIGCHLD to their parent when they exit but the parent can't handle signals while it's waiting for socket_accept (blocking).
Here is a piece of code that makes a non-blocking forking server.
#!/usr/bin/php -q
<?php
/**
* Listens for requests and forks on each connection
*/
$__server_listening = true;
error_reporting(E_ALL);
set_time_limit(0);
ob_implicit_flush();
declare(ticks = 1);
become_daemon();
/* nobody/nogroup, change to your host's uid/gid of the non-priv user */
change_identity(65534, 65534);
/* handle signals */
pcntl_signal(SIGTERM, 'sig_handler');
pcntl_signal(SIGINT, 'sig_handler');
pcntl_signal(SIGCHLD, 'sig_handler');
/* change this to your own host / port */
server_loop("127.0.0.1", 1234);
/**
* Change the identity to a non-priv user
*/
function change_identity( $uid, $gid )
{
if( !posix_setgid( $gid ) )
{
print "Unable to setgid to " . $gid . "!\n";
exit;
}
if( !posix_setuid( $uid ) )
{
print "Unable to setuid to " . $uid . "!\n";
exit;
}
}
/**
* Creates a server socket and listens for incoming client connections
* @param string $address The address to listen on
* @param int $port The port to listen on
*/
function server_loop($address, $port)
{
GLOBAL $__server_listening;
if(($sock = socket_create(AF_INET, SOCK_STREAM, 0)) < 0)
{
echo "failed to create socket: ".socket_strerror($sock)."\n";
exit();
}
if(($ret = socket_bind($sock, $address, $port)) < 0)
{
echo "failed to bind socket: ".socket_strerror($ret)."\n";
exit();
}
if( ( $ret = socket_listen( $sock, 0 ) ) < 0 )
{
echo "failed to listen to socket: ".socket_strerror($ret)."\n";
exit();
}
socket_set_nonblock($sock);
echo "waiting for clients to connect\n";
while ($__server_listening)
{
$connection = @socket_accept($sock);
if ($connection === false)
{
usleep(100);
}elseif ($connection > 0)
{
handle_client($sock, $connection);
}else
{
echo "error: ".socket_strerror($connection);
die;
}
}
}
/**
* Signal handler
*/
function sig_handler($sig)
{
switch($sig)
{
case SIGTERM:
case SIGINT:
exit();
break;
case SIGCHLD:
pcntl_waitpid(-1, $status);
break;
}
}
/**
* Handle a new client connection
*/
function handle_client($ssock, $csock)
{
GLOBAL $__server_listening;
$pid = pcntl_fork();
if ($pid == -1)
{
/* fork failed */
echo "fork failure!\n";
die;
}elseif ($pid == 0)
{
/* child process */
$__server_listening = false;
socket_close($ssock);
interact($csock);
socket_close($csock);
}else
{
socket_close($csock);
}
}
function interact($socket)
{
/* TALK TO YOUR CLIENT */
}
/**
* Become a daemon by forking and closing the parent
*/
function become_daemon()
{
$pid = pcntl_fork();
if ($pid == -1)
{
/* fork failed */
echo "fork failure!\n";
exit();
}elseif ($pid)
{
/* close the parent */
exit();
}else
{
/* child becomes our daemon */
posix_setsid();
chdir('/');
umask(0);
return posix_getpid();
}
}
?>
13-Jun-2007 07:20
socket_accept with timeout, seems to work for me on Apache/1.3.37 (FreeBSD 6.0) PHP/4.4.7.
Adapted from ScriptBlue at nyc dot rr dot com's post under socket_connect.
<?php
$socket = socket_create(AF_INET,SOCK_STREAM,SOL_TCP);
socket_bind($socket,$address,$port);
socket_listen($socket);
echo "Waiting for a connection\n";
$conn = false;
switch(@socket_select($r = array($socket), $w = array($socket), $e = array($socket), 60)) {
case 2:
echo "Connection refused\n";
break;
case 1:
echo "Connection accepted\n";
$conn = @socket_accept($socket);
break;
case 0:
echo "Connection timed out\n";
break;
}
if ($conn !== false) {
// communicate over $conn
}
?>
22-May-2007 06:15
Be aware signal handler functions set with pcntl_signal are not called while a socket is blocking waiting for a connection; the signal is absorbed silently and the handler called when a connection is made.
16-May-2005 05:11
>Accepting a connection using php-sockets:
>
>$fd = socket_create(AF_INET, SOCK_STREAM, 6 /* OR >getprotobyname("TCP")*/);
>
>$PORT = 5000;
>
>socket_bind($fd, "0.0.0.0", $PORT);
>
>while(true)
>{
>$remote_fd = socket_accept($fd);
>
>remote_socket_client_handle($remote_fd);
>
>}
>
>It is simple!
This example doesn't work. You have to call socket_listen($fd) after your bind in order to accept incoming connections.
Simon
11-Dec-2003 09:49
The socket returned by this resource will be non-blocking, regardless of what the listening socket is set to. This is actually true for all FCNTL modifiers.
18-Aug-2003 10:32
Accepting a connection using php-sockets:
$fd = socket_create(AF_INET, SOCK_STREAM, 6 /* OR getprotobyname("TCP")*/);
$PORT = 5000;
socket_bind($fd, "0.0.0.0", $PORT);
while(true)
{
$remote_fd = socket_accept($fd);
remote_socket_client_handle($remote_fd);
}
It is simple!
