is_resource — Tests whether a value is a resource
mixed value: Variable or
value to test
TRUE if the value is a resource pointer; FALSE otherwise
is_resource() checks whether value is a resource pointer that has been
returned by a call to fopen() , popen() , opendir() , etc., or one of
the database functions such as mysql_connect() , msql_pconnect() , etc. If so, the function
returns TRUE. If not,FALSE is returned.
PHP Version: 3+, 4+
Example 1398. Test whether a
value is a resource pointer
$dir_handle = opendir ('..');
if (is_resource ($dir_handle))
print '$dir_handle is a resource pointer.';
print '$dir_handle is not a resource pointer.';
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
The authors of this book have elected not to choose any options under the OPL. This online book was obtained
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.