pfsockopen() attempts to open a persistent connection to a network socket on the specified host and port. This function differs from fsockopen() only in that the connection is not closed after the script finishes; the connection can therefore be reused by other script instances running in the same PHP process. TCP connections are assumed by default, but UDP connections can be specified by placing udp:// at the start of the host .
There are three optional arguments: error_number , error_string , and timeout . Both the error_number and error_string arguments must be passed as references, as in &$error_numberand&$error_string. If an error occurs, these variables will contain an error code and message. If the error number is 0, this is usually due to a problem that occurs before the socket initializes, such as an incorrect hostname.
The timeout argument should contain the maximum number of seconds to wait for the connection to open.
<?php $host = 'www.google.com'; $port = 80; $fp = pfsockopen($host, $port, &$err_no, &$err_msg, 10) or die ("Could not open a connection to host <i>$host</i> on port <i>$port</i>. The error message returned was '<i>$err_msg</i>'."); echo "A persistent connection to host <i>$host</i> on port <i>$port</i> was successfully opened." ?>
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing (Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch). This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/). The authors of this book have elected not to choose any options under the OPL. This online book was obtained from http://www.fooassociates.com/phpfer/ and is designed to provide information about the PHP programming language, focusing on PHP version 4.0.4 for the most part. The information is provided on an as-is basis, and no warranty or fitness is implied. All persons and entities shall have neither liability nor responsibility to any person or entity with respect to any loss or damage arising from the information contained in this book.