readline_info() reads or changes readline runtime settings such as prompt or editing mode. This guide explains the function with focused examples and the decisions that matter in real applications.
What Is readline_info() in PHP?
Reads or changes readline runtime settings such as prompt or editing mode.
A typical call looks like this:
<?php
readline_info([$var_name], [$value]);
The input arguments shown in the call identify the relevant connection, resource, value, path or configuration for the operation. Pay attention to argument order and to the return value demonstrated below.
Example 1: Basic Usage
This first example uses readline_info() directly to demonstrate its basic purpose.
<?php
echo readline_info("library_version");
The returned value illustrates reads or changes readline runtime settings such as prompt or editing mode. Writable settings vary by installed readline implementation.
Example 2: A Different Input or Option
The next example changes the input or option, showing another supported use of readline_info().
<?php
print_r(readline_info());
The returned value illustrates reads or changes readline runtime settings such as prompt or editing mode. Writable settings vary by installed readline implementation.
Practical Example: Applying the Function
In application code, readline_info() belongs in a controlled workflow with input validation, a checked result and cleanup where needed.
<?php
$settings = readline_info(); echo isset($settings["line_buffer"]) ? "Buffer available" : "No buffer";
The returned value illustrates reads or changes readline runtime settings such as prompt or editing mode. Writable settings vary by installed readline implementation.
Important Behavior and Edge Cases
- Main behavior: Reads or changes readline runtime settings such as prompt or editing mode.
- Important limitation: Writable settings vary by installed readline implementation.
- Requirements: This function uses the CLI readline extension; it is not designed for an ordinary web request.
Comparison With Related Functions
| Function or Approach | When to Use It |
|---|---|
readline_info() | Reads or changes readline runtime settings such as prompt or editing mode. |
readline | Reads an interactive line of input from a terminal. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
Ignoring the specific limits or preconditions of readline_info(). | Writable settings vary by installed readline implementation. |
| Assuming every environment produces the same result. | This function uses the CLI readline extension; it is not designed for an ordinary web request. |
Key Takeaways
- Reads or changes readline runtime settings such as prompt or editing mode.
- Writable settings vary by installed readline implementation.
- This function uses the CLI readline extension; it is not designed for an ordinary web request.
Use readline_info() when its behavior matches your task, and verify the relevant return value before taking further action. The output depends on the local configuration when it uses resources, files or an interactive terminal.