stream_socket_recvfrom()

stream_socket_recvfrom() — Receives data from a socket, connected or not.

Built-in function of PHP 8.5. The manual lists it as available in PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

stream_socket_recvfrom() accepts data from a remote socket up to length bytes.

Signature

stream_socket_recvfrom(resource $socket, int $length, int $flags = 0, ?string &$address = null): string|false

Parameters

Parameter	Type	What it takes
$socket	resource	The remote socket.
$length	int	The number of bytes to receive from the socket.
$flags	int	The value of flags can be any combination of the following: Possible values for flags STREAM_OOB Process OOB (out-of-band) data. STREAM_PEEK Retrieve data from the socket, but do not consume the buffer. Subsequent calls to fread() or stream_socket_recvfrom() will see the same data.
&$address	?string	If address is provided it will be populated with the address of the remote socket.

Return value

Returns the read data, as a string, or false on failure.

Example

A runnable snippet:

/* Open a server socket to port 1234 on localhost */ $server = stream_socket_server('tcp://127.0.0.1:1234'); /* Accept a connection */ $socket = stream_socket_accept($server); /* Grab a packet (1500 is a typical MTU size) of OOB data */ echo "Received Out-Of-Band: '" . stream_socket_recvfrom($socket, 1500, STREAM_OOB) . "'\n"; /* Take a peek at the normal in-band data, but don't consume it. */ echo "Data: '" . stream_socket_recvfrom($socket, 1500, STREAM_PEEK) . "'\n"; /* Get the exact same packet again, but remove it from the buffer this time. */ echo "Data: '" . stream_socket_recvfrom($socket, 1500) . "'\n"; /* Close it up */ fclose($socket); fclose($server);

Changelog

Version	Change
8.0.0	Now throws a ValueError if length is less than 1. Previously, an E_WARNING was raised and false was returned.