readfile

(PHP 4, PHP 5)

readfileOutputs a file

Description

int readfile ( string $filename [, bool $use_include_path = false [, 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:

Open / Save dialogue

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. See the List of Supported Protocols/Wrappers for links to information about what abilities the various wrappers have, notes on their usage, and information on any predefined variables they may provide.

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

See Also