Use ini_alter() when you need to changes an allowed PHP configuration setting and is an alias of ini_set() in a PHP application. The examples below show the actual operation and its limitations.
What Is ini_alter() in PHP?
Changes an allowed PHP configuration setting and is an alias of ini_set(). The exact signature supported by your installation depends on its PHP version and enabled extensions.
Its syntax is:
ini_alter(string $option, string|int|float|bool|null $value): string|falseParameters 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
$original = ini_get("display_errors"); ini_alter("display_errors","0"); ini_set("display_errors",$original); echo "Restored";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
echo function_exists("ini_alter") ? "Alias available" : "Missing";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
$setting = "precision"; $previous = ini_get($setting); ini_alter($setting,"14"); ini_set($setting,$previous); echo "Runtime option restored";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
Only settings allowed at runtime can be changed; aliases offer no extra privileges.
Comparison With Related Functions
| Approach | Difference |
|---|---|
ini_alter() | Changes an allowed PHP configuration setting and is an alias of ini_set(). |
| Related operation | ini_set() is the canonical name; ini_alter() is an alias. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Ignoring the function-specific limitation | Only settings allowed at runtime can be changed; aliases offer no extra privileges. |
| Confusing this function with a related operation | ini_set() is the canonical name; ini_alter() is an alias. |
Key Takeaways
- Changes an allowed PHP configuration setting and is an alias of ini_set().
- Only settings allowed at runtime can be changed; aliases offer no extra privileges.
- ini_set() is the canonical name; ini_alter() is an alias.
Use ini_alter() for the specific operation demonstrated above. Check its prerequisites and handle failure conditions before using it with production data.