(debian-policy.info)Providing media types to files (debian-policy.info)Providing media types to files9.7.3 Providing media types to files ------------------------------------ The media type of a file is discovered by inspecting the file’s extension or its magic(5) pattern, and interrogating a database associating them with media types. To support new associations between media types and files, their characteristic file extensions and magic patterns should be registered to the IANA (Internet Assigned Numbers Authority). See ‘https://www.iana.org/assignments/media-types’ and RFC 6838 for details. This information will then propagate to the systems discovering file media types in Debian, provided by the shared-mime-info, mime-support and file packages. If registration and propagation can not be waited for, support can be asked to the maintainers of the packages mentioned above. For files that are produced and read by a single application, it is also possible to declare this association to the `Shared MIME Info' system by installing in the directory ‘/usr/share/mime/packages’ a file in the XML format specified at ‘https://standards.freedesktop.org/shared-mime-info-spec/latest/’.