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socket_getpeername

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

socket_getpeernameQueries the remote side of the given socket

Description

socket_getpeername(Socket $socket, string &$address, int &$port = null): bool

Queries the remote side of the given socket which may either result in host/port or in a Unix filesystem path, dependent on its type.

Parameters

socket

A Socket instance created with socket_create() or socket_accept().

address

If the given socket is of type AF_INET or AF_INET6, socket_getpeername() will return the peers (remote) IP address in appropriate notation (e.g. 127.0.0.1 or fe80::1) in the address parameter and, if the optional port parameter is present, also the associated port.

If the given socket is of type AF_UNIX, socket_getpeername() will return the Unix filesystem path (e.g. /var/run/daemon.sock) in the address parameter.

port

If given, this will hold the port associated to address.

Return Values

Returns true on success or false on failure. socket_getpeername() may also return false if the socket type is not any of AF_INET, AF_INET6, or AF_UNIX, in which case the last socket error code is not updated.

Changelog

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

Notes

Note:

socket_getpeername() should not be used with AF_UNIX sockets created with socket_accept(). Only sockets created with socket_connect() or a primary server socket following a call to socket_bind() will return meaningful values.

Note:

For having socket_getpeername() to return a meaningful value, the socket it is applied upon must of course be one for which the concept of "peer" makes sense.

See Also

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User Contributed Notes 2 notes

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3
redph0enix at hotmail dot com
21 years ago
socket_getpeername will not work for UDP sockets. Instead, use socket_recvfrom - it provides the IP address and port of the source server - eg:

$size=socket_recvfrom($socket,$input,65535,0,$ipaddress,$port);
echo "Received [$input] ($size bytes) from IP $ipaddress Port $port\n";
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2
Anonymous
8 years ago
The reason it won't work for UDP is that UDP is stateless; logically there are no peers other than at the time a packet is sent or received. Or more strictly, a UDP socket can interact with 0..N peers.
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