Register file extensions / mime types in Linux

Question

I\'m developing a Linux application that has its own file format. I want my app to open when you double-click on those files.

How can I register a file extension and

Answer 1

There are two parts to this. You need to register a new file type and then create a desktop entry for your application. The desktop entry associates your application with your new mime type.

I thought that both Gnome and KDE (maybe only 4+?) used the freedesktop shared mime info spec, but I may well be wrong.