File association doesn't seem to work

[pwabrahams]

I'm trying to arrange to have Playlist files with extension m3u be opened by Kate. I set that up in System Settings/ File Associations, but it doesn't seem to take. Opening the file Play3.m3u invokes Sound Converter instead. I've attached a screenshotof File Associations. What am I missing?

[GreyGeek]

Re: File association doesn't seem to work

I don't believe that "Playlist" is a known file type.

If you use the search option on that association dialog and search for m3u you will find vnd.apple.mpegurl
under "Applications" and x-mpegurl under "Audio". I believe that the "Application" type is the one you want.

Also, the correct extension format is *.xxx, so you should put
*.m3u
*m3u8
in the filename pattern box. They are already showing for the vnd.apple.mpegurl file type. Just add "Kate" or "Kate-2" to the list of applications.

[pwabrahams]

*.m3u listed for several types

Playlist was a type I added under "audio".

I discovered, though, that there were two other types that also had *.m3u files. When I changed the order of applications under xmpe-gurl the problem was solved.

But a couple of questions remain:

1. Why is it "Kate" rather than "kate"?

2. When several types list the same filename pattern, is there any rule that determines which one is chosen, or is it just the luck of the draw?

Thanks for your help, GreyGeek, yet again.

[GreyGeek]

Re: *.m3u listed for several types

Playlist was a type I added under "audio".

I know. But, it wasn't recognized because it wasn't pre-defined.

...
1. Why is it "Kate" rather than "kate"?

The binary is stored as "kate". In the File Assoications dialog, the names of the file are capitalized, even though within the dialog they are stored as the package named them. So, Kate is displayed, but kate is used.

2. When several types list the same filename pattern, is there any rule that determines which one is chosen, or is it just the luck of the draw?
...

Although several filename patterns may be shown, (*.m3u, *.m3u8) and several Applications may be listed, the Applications are tried in order, from the top down, until one does not return an error and begin operating properly using the file depicted by the filename pattern.

As far as which filename pattern, there is no confusion about that. IF the playlist you are working with end with .m3u then that pattern is is a "key" which is used to looked up in the database (that File Associations keeps in the background) the applications which are associated with that filename pattern. The first one is tried (in the background, without user visible notices, except for a set of spinning balls (busy icon). If it works the File Association search ceases, focus is given to the chosen application . which begins using the file which initiated the search, and the chosen application and the *.m3u (or *.m3u8) take center stage. If that application returns an error (silently) then the next one is tested, and so on.

[pwabrahams]

Re: *.m3u listed for several types

Although several filename patterns may be shown, (*.m3u, *.m3u8) and several Applications may be listed, the Applications are tried in order, from the top down, until one does not return an error and begin operating properly using the file depicted by the filename pattern.

I actually was asking a slightly different question. If a particular filename pattern appears under several types, how is the applicable type chosen? (The types are ordered alphabetically in the File Associations screen, so I'd guess that the order has nothing to do with the priority.)

[steing]

Re: File association doesn't seem to work

I don't know what type is assumed, but IMHO it should not consult the file name extension at all, but use the magic files, same as the file command.

[GreyGeek]

Re: File association doesn't seem to work

Magic was originally used by the "file" command. See "man magic" to read about that.

File Association is about the mime type. Rather than paste a lot of stuff here, you can read the shared mime info on your own local system here: file:///usr/share/doc/shared-mime-info/shared-mime-info-spec.html/index.html.


To see how this relates to desktops read: http://www.linuxtopia.org/online_boo...ociations.html