What is the usage of realpath in PHP?

In PHP, the realpath() function is used to return the absolute path of a given file. If the specified path does not exist, it returns false. This function is typically used to obtain the absolute path of a file or directory for further processing in a program.

The syntax for the realpath() function is as follows:

realpath ( string $path ) : string|false

原文：我现在很忙，明天再给你打电话。

Paraphrase: I’m busy right now, I’ll give you a call tomorrow.

$absolutePath = realpath('example.txt');
echo $absolutePath;

In the above example, the realpath() function will return the absolute path of the file example.txt and then output it to the screen.