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readfile

PHP function Edit on GitHub ✎

(PHP 4, PHP 5, PHP 7, PHP 8)

Outputs a file

Description

readfile(string $filename, bool $use_include_path = false, resource|null $context = null): int|false

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: Context-support

Return Values

Returns the number of bytes read from the file on success, Falseforfailure

Errors/Exceptions Failure

Examples

Forcing a download using readfile()

php

<?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('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    readfile($file);
    exit;
}
?>

The above example will output something similar to: Open / Save dialogue

Notes

Note

readfile() will not present any memory issues, even when sending large files, on its own. If you encounter an out of memory error ensure that output buffering is off with ob_get_level().

Fopen-wrapper