Using sockets to get articles from newsgroups 1_PHP tutorial
By Armel Fauveau 一木
PHP can open the Socket port on the remote or local host. This article is a small example of using Socket: connect to a Usenet news group server, talk to the server, and download some articles from the news group.
Open a socket in php
Use fsockopen() to open a socket. This function can be used in both php3 and php4. The function declaration is like this:
int fsockopen (string hostname, int port [, int errno [, string errstr [, double timeout]]])
This function will open a TCP connection to the port of the host hostname connect. hostname can be a valid domain name, or an IP address. For udp connections, you must specify the protocol: udp://hostname. For unix domains, the hostname uses the path to the socket. In this case, port must be set to 0. The optional timeout parameter is used to set the time to wait to open a socket, in seconds.
For more information about fsockopen(), please refer to: http://www.php.net/manual/function.fsockopen.php
Network News Transfer Protocol
Accessing the newsgroup server requires a pass called NNTP (Network News Transfer Protocol) protocol. This protocol is detailed in rfc977, which is available at http://www.w3.org/Protocols/rfc977/rfc977.html. This document describes how to connect to an NNTP server, how to talk to the server, and the different commands to accomplish these tasks.
Connect
Connecting to an NNTP server requires knowing its hostname (or IP address) and the port it is listening on. To avoid a failed connection attempt causing the program to hang, you should use the timeout parameter.
$cfgServer = "your.news.host";
$cfgPort = 119;
$cfgTimeOut = 10;
//open a socket
if(!$cfgTimeOut)
// without timeout
$usenet_handle = fsockopen($cfgServer, $cfgPort);
else
// with timeout
$usenet_handle = fsockopen($cfgServer, $cfgPort, &$errno, &$errstr, $cfgTimeOut);
if(!$usenet_handle) {
echo "Connection failed. ";
exit();
}
else {
echo "Connected. ";
$tmp = fgets($usenet_handle, 1024);
}
?>

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