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    socket_bind

    (PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

    socket_bind — Binds a name to a socket

    Description

    socket_bind(Socket $socket, string $address, int $port = 0): bool

    Binds the name given in address to the socket described by socket. This has to be done before a connection is be established using socket_connect() or socket_listen().

    Parameters

    socket

    A Socket instance created with socket_create().

    address

    If the socket is of the AF_INET family, the address is an IP in dotted-quad notation (e.g. 127.0.0.1).

    If the socket is of the AF_UNIX family, the address is the path of a Unix-domain socket (e.g. /tmp/my.sock).

    port (Optional)

    The port parameter is only used when binding an AF_INET socket, and designates the port on which to listen for connections.

    Return Values

    Returns true on success or false on failure.

    The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual explanation of the error.

    Changelog

    Version Description
    8.0.0 socket is a Socket instance now; previously, it was a resource.

    Examples

    Example #1 Using socket_bind() to set the source address

    <?php
    // Create a new socket
    $sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

    // An example list of IP addresses owned by the computer
    $sourceips['kevin'] = '127.0.0.1';
    $sourceips['madcoder'] = '127.0.0.2';

    // Bind the source address
    socket_bind($sock, $sourceips['madcoder']);

    // Connect to destination address
    socket_connect($sock, '127.0.0.1', 80);

    // Write
    $request = 'GET / HTTP/1.1' . "\r\n" .
    'Host: example.com' . "\r\n\r\n";
    socket_write($sock, $request);

    // Close
    socket_close($sock);

    ?>

    Notes

    Note:

    This function must be used on the socket before socket_connect().

    Note:

    Windows 9x/ME compatibility note: socket_last_error() may return an invalid error code if trying to bind the socket to a wrong address that does not belong to your machine.

    See Also

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    User Contributed Notes 6 notes

    up
    8
    dresende at thinkdigital dot pt
    11 years ago
    Regarding previous post:

    "0" has address is no different from "0.0.0.0"

    127.0.0.1 -> accept only from local host
    w.x.y.z (valid local IP) -> accep only from this network
    0.0.0.0 -> accept from anywhere
    up
    12
    keksov[at]gmx.de
    20 years ago
    If you want to reuse address and port, and get rid of error: unable to bind, address already in use, you have to use socket_setopt (check actual spelling for this function in you PHP verison) before calling bind:

    <?php
    if (!socket_set_option($sock, SOL_SOCKET, SO_REUSEADDR, 1)) {
        echo     socket_strerror(socket_last_error($sock));
        exit;
    }
    ?>

    This solution was found by
    Christophe Dirac. Thank you Christophe!
    up
    3
    php50613160534 dot 3 dot korkman at spamgourmet dot org
    17 years ago
    Use 0 for port to bind a random (free) port for incoming connections:

    socket_bind ($socket, $bind_address, 0);
    socket_getsockname($socket, $socket_address, $socket_port);
    socket_listen($socket);
    ...

    $socket_port contains the assigned port, you might want to send it to a remote client connecting. Tested with php 5.03.
    up
    2
    gasket at cekkent dot net
    19 years ago
    The aforementioned tidbit about using NULL to bind to all addresses did not work for me, as I would receive an error about unknown address. Using a 0 worked for me:

    socket_bind ($socket, 0, $port)

    This also allows you to receive UDP broadcasts, which is what I had been trying to figure out.
    up
    -2
    gabriel at plenitech dot fr
    9 years ago
    When doing Unix sockets, it might be necessary to chmod the socket file so as to give Write permission to Group and/or Others. Otherwise, only the owner is allowed to write data into the stream.

    Example:

    <?php
    $sockpath     = '/tmp/my.sock';
    socket_bind($socket, $sockpath);
    //here: write-only (socket_send) to others, only owner can fetch data.
    chmod($sockpath, 0702);
    ?>
    up
    -11
    Mex
    11 years ago
    It appears for the $address parameter:

    '127.0.0.1'
    accepts clients from localhost (eg. 127.0.0.1)

    '0.0.0.0'
    accepts clients from localhost, and the server's network (eg. 127.0.0.1, 192.168.2.5, 10.20.30.40)

    '0' or 0
    accepts clients from localhost, the server's network, and external networks (eg. 127.0.0.1, 192.168.2.5, 10.20.30.40, 209.85.169.99)
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