PHP Resource Types and Handles

Resource values represent certain open external handles such as file streams.

What It Does

Resource values represent certain open external handles such as file streams. The following examples distinguish a normal use case, a boundary case and a practical application.

Requirements and Compatibility

PHP 8.x and a local test environment. Apply input validation, correct error handling and the requirements of any optional libraries.

The code focuses on the core concept. Production implementation may also need routes, validation, persistence, authorization or deployment tooling.

Example 1: Basic Behavior

Start with the smallest meaningful working case.

<?php
$stream = fopen('php://temp', 'w+');
var_dump(get_resource_type($stream));
fclose($stream);

Example 2: Another Case

Examine the edge case and the observable result.

<?php
$handle = fopen('php://memory', 'w+');
fwrite($handle, 'sample'); rewind($handle); echo stream_get_contents($handle); fclose($handle);

Practical Example: Putting It to Use

Apply the technique to a small practical task.

<?php
$file = fopen('php://temp', 'rb');
var_dump(is_resource($file));
fclose($file);
var_dump(is_resource($file));

Important Behavior and Edge Cases

PHP 8 converted many extensions from resources to dedicated objects, so types vary by API.

Comparison with Related Functions or Approaches

Common Beginner Mistakes

Key Takeaways

• Resource values represent certain open external handles such as file streams.
• PHP 8 converted many extensions from resources to dedicated objects, so types vary by API.
• Always close acquired streams and handle false results.

Before adapting these examples, verify the return values, test the failure paths and confirm that your application meets its security and environment requirements.