PHP Manual
Stream Functions
Receives data from a socket, connected or not

stream_socket_recvfrom

(PHP 5, PHP 7, PHP 8)

stream_socket_recvfrom — Receives data from a socket, connected or not

Description

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

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

Parameters

socket

The remote socket.

length

The number of bytes to receive from the socket.

flags

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

If address is provided it will be populated with the address of the remote socket.

Return Values

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

Examples

Example #1 stream_socket_recvfrom() example


<?php
/* 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);
?>

Notes

Note:
If a message received is longer than the length parameter, excess bytes may be discarded depending on the type of socket the message is received from (such as UDP).

Note:
Calls to stream_socket_recvfrom() on socket-based streams, after calls to buffer-based stream functions (like fread() or stream_get_line()) read data directly from the socket and bypass the stream buffer.