PHP gc_enable() Function: Usage and Examples

Use gc_enable() when you need to enables automatic cycle collection in a PHP application. The examples below show the actual operation and its limitations.

What Is gc_enable() in PHP?

Enables automatic cycle collection. The exact signature supported by your installation depends on its PHP version and enabled extensions.

Its syntax is:

gc_enable(): void

Parameters and return value: The parameter types, optional arguments, references, and return type are shown in the signature above. Optional parameters are marked with an ellipsis in this reference signature.

Example 1: Basic Usage

<?php

gc_disable(); gc_enable(); var_dump(gc_enabled());

Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.

Example 2: Different Input or Behavior

<?php

gc_enable(); echo gc_enabled() ? "On" : "Off";

Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.

Practical Example: Applying the Function

<?php

$previousSetting = gc_enabled(); gc_enable(); echo "Collector available"; if (!$previousSetting) gc_disable();

Result: Run the example in an environment that supports the function. Any values depending on operating-system state, installed extensions, process configuration, or network access must be checked on the target server.

Important Behavior and Edge Cases

Automatic collection is generally desirable; disabling it requires a measured reason.

Comparison With Related Functions

Common Beginner Mistakes

Key Takeaways

• Enables automatic cycle collection.
• Automatic collection is generally desirable; disabling it requires a measured reason.
• gc_disable() disables automatic cycle collection; gc_enable() re-enables it.

Use gc_enable() for the specific operation demonstrated above. Check its prerequisites and handle failure conditions before using it with production data.