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# NAME
File::LibMagic - Determine MIME types of data or files using libmagic
# VERSION
version 1.02
# SYNOPSIS
use File::LibMagic;
my $magic = File::LibMagic->new();
# prints a description like "ASCII text"
print $magic->describe_filename('path/to/file');
print $magic->describe_contents('this is some data');
# Prints a MIME type like "text/plain; charset=us-ascii"
print $magic->checktype_filename('path/to/file');
print $magic->checktype_contents('this is some data');
# DESCRIPTION
The `File::LibMagic` is a simple perl interface to libmagic from the file
package (version 4.x or 5.x). You will need both the library (`libmagic.so`)
and the header file (`magic.h`) to build this Perl module.
## Installing libmagic
On Debian/Ubuntu run:
sudo apt-get install libmagic-dev
On Mac you can use homebrew (http://brew.sh/):
brew install libmagic
# API
This module provides an object-oriented API with the following methods:
## File::LibMagic->new()
Creates a new File::LibMagic object.
Using the object oriented interface provides an efficient way to repeatedly
determine the magic of a file.
Each File::LibMagic object loads the magic database independently of other
File::LibMagic objects, so you may want to share a single object across many
modules as a singleton.
This method takes an optional argument containing a path to the magic file. If
the file doesn't exist this will throw an exception (but only with libmagic
4.17+).
If you don't pass an argument, it will throw an exception if it can't find any
magic files at all.
## $magic->checktype\_contents($data)
Returns the MIME type of the data given as the first argument. The data can be
passed as a plain scalar or as a reference to a scalar.
This is the same value as would be returned by the `file` command with the
`-i` switch.
## $magic->checktype\_filename($filename)
Returns the MIME type of the given file.
This is the same value as would be returned by the `file` command with the
`-i` switch.
## $magic->describe\_contents($data)
Returns a description (as a string) of the data given as the first argument.
The data can be passed as a plain scalar or as a reference to a scalar.
This is the same value as would be returned by the `file` command with no
switches.
## $magic->describe\_filename($filename)
Returns a description (as a string) of the given file.
This is the same value as would be returned by the `file` command with no
switches.
# DEPRECATED APIS
This module offers two different procedural APIS based on optional exports,
the "easy" and "complete" interfaces. These APIS are now deprecated. I
strongly recommend you use the OO interface. It's simpler than the complete
interface and more efficient than the easy interface.
## The "easy" interface
This interface is exported by:
use File::LibMagic ':easy';
This interface exports two subroutines:
- MagicBuffer($data)
Returns the description of a chunk of data, just like the `describe_contents`
method.
- MagicFile($filename)
Returns the description of a file, just like the `describe_filename` method.
## The "complete" interface
This interface is exported by:
use File::LibMagic ':complete';
This interface exports several subroutines:
- magic\_open($flags)
This subroutine opens creates a magic handle. See the libmagic man page for a
description of all the flags. These are exported by the `:complete` import.
my $handle = magic_open(MAGIC_MIME);
- magic\_load($handle, $filename)
This subroutine actually loads the magic file. The `$filename` argument is
optional. There should be a sane default compiled into your `libmagic`
library.
- magic\_buffer($handle, $data)
This returns information about a chunk of data as a string. What it returns
depends on the flags you passed to `magic_open`, a description, a MIME type,
etc.
- magic\_file($handle, $filename)
This returns information about a file as a string. What it returns depends on
the flags you passed to `magic_open`, a description, a MIME type, etc.
- magic\_close($handle)
Closes the magic handle.
# EXCEPTIONS
This module can throw an exception if your system runs out of memory when
trying to call `magic_open` internally.
# SUPPORT
Please submit bugs to the CPAN RT system at
http://rt.cpan.org/NoAuth/Bugs.html?Dist=File-LibMagic or via email at
bug-file-libmagic@rt.cpan.org.
# BUGS
This module is totally dependent on the version of file on your system. It's
possible that the tests will fail because of this. Please report these
failures so I can make the tests smarter. Please make sure to report the
version of file on your system as well!
# DEPENDENCIES/PREREQUISITES
This module requires file 4.x or file 5x and the associated libmagic library
and headers (http://darwinsys.com/file/).
# RELATED MODULES
Andreas created File::LibMagic because he wanted to use libmagic (from
file 4.x) [File::MMagic](https://metacpan.org/pod/File::MMagic) only worked with file 3.x.
[File::MimeInfo::Magic](https://metacpan.org/pod/File::MimeInfo::Magic) uses the magic file from freedesktop.org which is
encoded in XML, and is thus not the fastest approach. See
[http://mail.gnome.org/archives/nautilus-list/2003-December/msg00260.html](http://mail.gnome.org/archives/nautilus-list/2003-December/msg00260.html)
for a discussion of this issue.
File::Type uses a relatively small magic file, which is directly hacked into
the module code. It is quite fast but the database is quite small relative to
the file package.
# AUTHORS
- Andreas Fitzner
- Michael Hendricks <michael@ndrix.org>
- Dave Rolsky <autarch@urth.org>
# COPYRIGHT AND LICENSE
This software is copyright (c) 2014 by Andreas Fitzner, Michael Hendricks, and Dave Rolsky.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
|
