LVII. Mimetype Functions

Introduction

The functions in this module try to guess the content type and encoding of a file by looking for certain magic byte sequences at specific positions within the file. While this is not a bullet proof approach the heuristics used do a very good job.

This extension is derivated from Apache mod_mime_magic, which is itself based on the file command maintaind by Ian F. Darwin. See the source code for further historic and copyright information.

Requirements

No external libraries are needed to build this extension.

Installation

You must compile PHP with the configure switch --enable-mime-magic to get support for mime-type functions. The extension needs a copy of the magic.mime as distributed with the file command. This file also part of most recent Linux distributions and usually stored in the /usr/share/misc directory.

Runtime Configuration

The behaviour of these functions is affected by settings in php.ini.

Table 1. Mimetype configuration options

NameDefaultChangeable
mime_magic.magicfile"/usr/share/misc/magic.mime"PHP_INI_SYSTEM
For further details and definition of the PHP_INI_* constants see ini_set().

Resource Types

This extension has no resource types defined.

Predefined Constants

This extension has no constants defined.

Table of Contents
mime_content_type -- Detect MIME Content-type for a file