regfiletype — Identify the formats of Regina data files


regfiletype {file...}


This utility determines which file format a given Regina data file is in. You may pass multiple files on the command line; the format of each file will be written to standard output.

Only Regina's modern XML-based file formats are recognised (both compressed and uncompressed). In its very early years, Regina used an impenetrable and undocumented binary format; this was replaced with XML in 2002 (Regina 3.0), and support for this format was removed completely in 2013 (Regina 4.94). If you still need to recognise and/or read files in this ancient binary format, you will need to download Regina 4.93.

MacOS Users

If you downloaded a drag-and-drop app bundle, this utility is shipped inside it. If you dragged Regina to the main Applications folder, you can run it as /Applications/

Windows Users

The command-line utilities are installed beneath the Program Files directory; on some machines this directory is called Program Files (x86). You can start this utility by running c:\Program Files\Regina\Regina 5.1\bin\regfiletype.exe.


This utility was written by Benjamin Burton . Many people have been involved in the development of Regina; see the acknowledgements page for a full list of credits.