php 开启 stream_socket_client,stream_socket_client

Descriptionresource 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.

The optional timeout can be used to

set a timeout in seconds for the connect system call.

flags is a bitmask field which may be set to any

combination of connection flags. Currently the selection of connection

flags is limited to STREAM_CLIENT_CONNECT (default),

STREAM_CLIENT_ASYNC_CONNECT and

STREAM_CLIENT_PERSISTENT.

注:

If you need to set a timeout for reading/writing data over the socket,

use stream_set_timeout(), as the timeout

parameter to stream_socket_client() only applies while

connecting the socket.

stream_socket_client() returns a

stream resource which may

be used together with the other file functions (such as

fgets(), fgetss(),

fwrite(), fclose(), and

feof()).

If the call fails, it will return FALSE and if the optional

errno and errstr

arguments are present they will be set to indicate 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.

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 附录 N for a list of built in transports.

The stream will by default be opened in blocking mode. You can

switch it to non-blocking mode by using

stream_set_blocking().例子 1. stream_socket_client() Example<?php

$fp=stream_socket_client("tcp://www.example.com:80",$errno,$errstr,30);

if (!$fp) {

echo"$errstr ($errno)
n";

} else {fwrite($fp,"GET / HTTP/1.0rnHost: www.example.comrnAccept: */*rnrn");

while (!feof($fp)) {

echofgets($fp,1024);

}fclose($fp);

}?>

The example below shows how to retrieve the day and time

from the UDP service "daytime" (port 13) in your own machine.

例子 2. Using UDP connection<?php

$fp=stream_socket_client("udp://127.0.0.1:13",$errno,$errstr);

if (!$fp) {

echo"ERROR: $errno - $errstr
n";

} else {fwrite($fp,"n");

echofread($fp,26);fclose($fp);

}?>

警告

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.

注:当指定数字的

IPv6 地址(例如 fe80::1)时必须将 IP 地址放在方括号内。例如

tcp://[fe80::1]:80。