readlink() returns the stored target path of a filesystem symbolic link. This guide explains the function with focused examples and the decisions that matter in real applications.
What Is readlink() in PHP?
Returns the stored target path of a filesystem symbolic link.
A typical call looks like this:
<?php
readlink($path);
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 readlink() directly to demonstrate its basic purpose.
<?php
$path = __DIR__ . "/current"; if (is_link($path)) echo readlink($path);
The returned value illustrates returns the stored target path of a filesystem symbolic link. A returned relative path is relative to the link location, not necessarily the current directory.
Example 2: A Different Input or Option
The next example changes the input or option, showing another supported use of readlink().
<?php
var_dump(@readlink(__FILE__));
The returned value illustrates returns the stored target path of a filesystem symbolic link. A returned relative path is relative to the link location, not necessarily the current directory.
Practical Example: Applying the Function
In application code, readlink() belongs in a controlled workflow with input validation, a checked result and cleanup where needed.
<?php
$shortcutPath = __DIR__ . "/latest"; if (is_link($shortcutPath)) { $target = readlink($shortcutPath); echo "Link points to: $target"; }
The returned value illustrates returns the stored target path of a filesystem symbolic link. A returned relative path is relative to the link location, not necessarily the current directory.
Important Behavior and Edge Cases
- Main behavior: Returns the stored target path of a filesystem symbolic link.
- Important limitation: A returned relative path is relative to the link location, not necessarily the current directory.
- Requirements: Check the runtime, file permissions and operating system when results depend on the environment.
Comparison With Related Functions
| Function or Approach | When to Use It |
|---|---|
readlink() | Returns the stored target path of a filesystem symbolic link. |
realpath | Resolves an existing path to an absolute canonical path instead of returning a symbolic link’s stored target. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
Ignoring the specific limits or preconditions of readlink(). | A returned relative path is relative to the link location, not necessarily the current directory. |
| Assuming every environment produces the same result. | Check the runtime, file permissions and operating system when results depend on the environment. |
Key Takeaways
- Returns the stored target path of a filesystem symbolic link.
- A returned relative path is relative to the link location, not necessarily the current directory.
- Check the runtime, file permissions and operating system when results depend on the environment.
Use readlink() 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.