---
name: "File::MimeInfo::Cookbook"
section: "3pm"
platform: "linux"
package: "perl-file-mimeinfo"
version: "0.37-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/File::MimeInfo::Cookbook"
---

# File::MimeInfo::Cookbook(3pm)

various code snippets

## NAME

File::MimeInfo::Cookbook - various code snippets

## DESCRIPTION

Some code snippets for non-basic uses of the File::MimeInfo module:

- **Matching an extension**

  A file does not have to actually exist in order to get a mimetype for it. This means that the following will work:

  ```
    my $extension = '*.txt';
    my $mimetype = mimetype( $extension );
  ```

- **Mimetyping an scalar**

  If you want to find the mimetype of a scalar value you need magic mimetyping; after all a scalar doesn't have a filename or inode. What you need to do is to use IO::Scalar :

  ```
    use File::MimeInfo::Magic;
    use IO::Scalar;
    my $io_scalar = new IO::Scalar \$data;
    my $mimetype = mimetype( $io_scalar );
  ```

  In fact most other `"IO::"` will work as long as they support the `seek()` and `read()` methods. Of course if you want really obscure things to happen you can always write your own IO object and feed it in there.

  Be aware that when using a filehandle like this you need to set the `":utf8"` binmode yourself if appropriate.

- **Mimetyping a filehandle**

  Regrettably for non-seekable filehandles like STDIN simply using an `"IO::"` object will not work. You will need to buffer enough of the data for a proper mimetyping. For example you could mimetype data from STDIN like this:

  ```
    use File::MimeInfo::Magic;
    use IO::Scalar;
    my $data;
    read(STDIN, $data, $File::MimeInfo::Magic::max_buffer);
    my $io_scalar = new IO::Scalar \$data;
    my $mimetype = mimetype( $io_scalar );
  ```

  Be aware that when using a filehandle like this you need to set the `":utf8"` binmode yourself if appropriate.

- **Creating a new filename**

  Say you have a temporary file that you want to save with a more proper filename.

  ```
    use File::MimeInfo::Magic qw#mimetype extensions#;
    use File::Copy;
    my $tmpfile = '/tmp/foo';
    my $mimetype = mimetype($tmpfile);
    my $extension = extensions($mimetype);
    my $newfile = 'untitled1';
    $newfile .= '.'.$extension if length $extension;
    move($tmpfile, $newfile);
  ```

- **Force the use of a certain database directory**

  Normally you just need to add the dir where your mime database lives to either the XDG\_DATA\_HOME or XDG\_DATA\_DIRS environment variables for it to be found. But in some rare cases you may want to by-pass this system all together. Try one of the following:

  ```
    @File::MimeInfo::DIRS = ('/home/me/share/mime');
    eval 'use File::MimeInfo';
    die if $@;
  ```

  or:

  ```
    use File::MimeInfo;
    @File::MimeInfo::DIRS = ('/home/me/share/mime');
    File::MimeInfo->rehash();
  ```

  This can also be used for switching between databases at run time while leaving other XDG configuration stuff alone.

## AUTHOR

Jaap Karssenberg \<pardus@cpan.org\> Maintained by Michiel Beijen \<mb@x14.nl\>

## COPYRIGHT

Copyright (c) 2005, 2012 Jaap G Karssenberg. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

## SEE ALSO

File::MimeInfo