Using PHP filemtime to Retrieve File Modification Time

PHP function filemtime can be used to obtain a file's last modification time. It takes a file path as its argument and returns a Unix timestamp representing the modification time.

In PHP you can use filemtime as follows:

$file_path = 'path/to/file.txt'; // file path
$modification_time = filemtime($file_path); // get last modification time

echo "File last modification time: " . date('Y-m-d H:i:s', $modification_time);

The code first defines a variable $file_path that should be replaced with the actual path of the file you want to inspect. It then calls filemtime with that path to obtain the timestamp, and uses date to format the timestamp into a readable date‑time string.

Code Example‑1: Get File Last Modification Time

$file_path = 'path/to/file.txt';
$modification_time = filemtime($file_path);

echo "File last modification time: " . date('Y-m-d H:i:s', $modification_time);

This example assumes the file path is 'path/to/file.txt'; you can change it as needed. The date function can output the modification time in any desired format.

Code Example‑2: Get Multiple Files' Last Modification Times

$files = array(
    'path/to/file1.txt',
    'path/to/file2.txt',
    'path/to/file3.txt'
);

foreach ($files as $file_path) {
    $modification_time = filemtime($file_path);
    echo "File: '" . basename($file_path) . "' last modification time: " . date('Y-m-d H:i:s', $modification_time) . "<br>";
}

In this example we define an array $files containing several file paths, iterate over it, retrieve each file's modification timestamp with filemtime, obtain the file name using basename, and format the timestamp with date.

Summary

This article demonstrates how to use PHP's filemtime function to retrieve a file's last modification time, convert the timestamp to a readable format with date, and provides code samples for handling both a single file and multiple files.