In Ubuntu 12.10 there was a nice app called Assogiate. It has ability to add new mimetype, add recognition by content of file and new icon, all done by mouse clicking. Now assogiate disappears from repos. Other programs doesn't have that ability. How to do it by hand?
For example:
I have a file test.lzx. This is a packed test file with LZX packer used mostly on Amiga. Gnome doesn't recognize it. If I test file with file
command I see:
$ file test.lzx
test.lzx: LZX compressed archive (Amiga)
Recognize that type of file by content is simple. At 0 offset (at the beginning of file) there is a LZX
string:
$ hexdump -C test.lzx | head -n 1
00000000 4c 5a 58 00 0c 00 0a 04 00 00 07 00 00 c0 0d 00 |LZX.............|
In Assogiate I was able to add search string and offset where Gnome have to look for this string.
Now question: how to add manually new mime type and make Gnome recognize it by file content?
Answers at
are not related to my question.