PHP allows us to download a file easily using built-in readfile() function. The readfile() function reads a file and writes it to the output buffer.
readfile() - Outputs a file
int readfile (string $filename, string $mode [, bool $use_include_path = FALSE [, resource $context ]] )
Reads a file and writes it to the output buffer.
filename: The filename being read.
use_include_path: You can use the optional second parameter and set it to TRUE, if you want to search for the file in the include_path, too.
context: A context stream resource.
Returns the number of bytes read from the file. If an error occurs, FALSE is returned and unless the function was called as @readfile(), an error message is printed.
PHP Download File Example: Text File
<?php $file_url = "https://nexladder.com/resource.txt"; header('Content-Type: application/octet-stream'); header('Content-Transfer-Encoding: utf-8'); header("Content-disposition: attachment; filename=\"" . basename($file_url) . "\""); readfile($file_url); ?>