Outputs a file

Description

int readfile ( string $filename [, bool $use_include_path [, resource $context ]] )

Reads a file and writes it to the output buffer.

Parameters

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.

Return Values

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.

Examples

Example #1 Forcing a download using readfile()


<?php
$file = 'monkey.gif';

if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename='.basename($file));
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    ob_clean();
    flush();
    readfile($file);
    exit;
}
?>

The above example will output something similar to:

Notes

Tip

A URL can be used as a filename with this function if the fopen wrappers have been enabled. See fopen() for more details on how to specify the filename and List of Supported Protocols/Wrappers for a list of supported URL protocols.

Note: Context support was added with PHP 5.0.0. For a description of contexts, refer to Stream Functions.