Function.stream-socket-client
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stream_socket_client — Open Internet or Unix domain socket connection
Inhaltsverzeichnis |
Beschreibung
resource stream_socket_client ( string $remote_socket [, int &$errno [, string &$errstr [, float $timeout [, int $flags [, resource $context ]]]]] )
Initiates a stream or datagram connection to the destination specified
by remote_socket
. The type of socket created
is determined by the transport specified using standard URL formatting:
transport://target. For Internet Domain sockets
(AF_INET) such as TCP and UDP, the target portion
of the remote_socket
parameter should consist of
a hostname or IP address followed by a colon and a port number. For Unix
domain sockets, the target
portion should point
to the socket file on the filesystem.
Hinweis:
The stream will by default be opened in blocking mode. You can
switch it to non-blocking mode by using
stream_set_blocking().
Parameter-Liste
- remote_socket
- Address to the socket to connect to.
- errno
- Will be set to the system level error number if connection fails.
- errstr
- Will be set to the system level error message if the connection fails.
- timeout
- Number of seconds until the connect() system call should timeout. Hinweis: This parameter only applies when not making asynchronous connection attempts. Hinweis: To set a timeout for reading/writing data over the socket, use the stream_set_timeout(), as the timeout only applies while making connecting the socket.
- flags
- Bitmask field which may be set to any combination of connection flags. Currently the select of connection flags is limited to STREAM_CLIENT_CONNECT (default), STREAM_CLIENT_ASYNC_CONNECT and STREAM_CLIENT_PERSISTENT.
- context
- A valid context resource created with stream_context_create().
Rückgabewerte
On success a stream resource is returned which may be used together with the other file functions (such as fgets(), fgetss(), fwrite(), fclose(), and feof()), FALSE on failure.
Fehler/Exceptions
On failure the errno
and
errstr
arguments will be populated with the actual
system level error that occurred in the system-level
connect() call. If the value returned in
errno
is 0 and the
function returned FALSE, it is an indication that the error
occurred before the connect() call. This is
most likely due to a problem initializing the socket. Note that
the errno
and
errstr
arguments will always be passed by
reference.
Beispiele
=== #1 stream_socket_client() example
<?php $fp = stream_socket_client("tcp://www.example.com:80", $errno, $errstr, 30); if (!$fp) { echo "$errstr ($errno)<br />\n"; } else { fwrite($fp, "GET / HTTP/1.0\r\nHost: www.example.com\r\nAccept: */*\r\n\r\n"); while (!feof($fp)) { echo fgets($fp, 1024); } fclose($fp); } ?>
<div class="example" id="stream===
Retrieving the day and time from the UDP service "daytime" (port 13) on localhost.
<?php $fp = stream_socket_client("udp://127.0.0.1:13", $errno, $errstr); if (!$fp) { echo "ERROR: $errno - $errstr<br />\n"; } else { fwrite($fp, "\n"); echo fread($fp, 26); fclose($fp); } ?>
Anmerkungen
Warnung
UDP sockets will sometimes appear to have opened without an error,
even if the remote host is unreachable. The error will only
become apparent when you read or write data to/from the socket.
The reason for this is because UDP is a "connectionless" protocol,
which means that the operating system does not try to establish
a link for the socket until it actually needs to send or receive data.
Hinweis: Wenn Sie eine numerische IPv6 Adresse
angeben, z.B.: fe80::1, müssen Sie die IP in eckige Klammern
schreiben, z.B: tcp://[fe80::1]:80.
Hinweis:
Depending on the environment, the Unix domain or the optional
connect timeout may not be available. A list of available
transports can be retrieved using stream_get_transports().
See Liste der unterstützten Socket-Transporter for a list of built in transports.