stream_socket_recvfrom

(PHP 5, PHP 7, PHP 8)

stream_socket_recvfrom — Receives data from a socket, connected or not

说明

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

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

参数

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.

返回值

Returns the read data, as a string

范例

示例 #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);
?>

注释

注意:

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).

注意:

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.

参见