Do we get the right file extension with mime.get_primary_extension(mime_type) ?

[erikos]

I copied a photo taken with Record on a usb key. The file extension shown when inserting on another machine was .jpe Since I did not knew that extension I checked the Sugar code path. What we actually do is, we merge all the existing mime/globs in a dictionary with the given mime type as key and then get the value of that key.

jfif
jpeg
jpg
jpe

In the blobs there are 4 keys (image/jpeg) and hence we do overwrite the value and end up with the last key-value pair found - in this case 'jpe'.

 http://git.sugarlabs.org/projects/sugar-base/repos/mainline/blobs/master/src/sugar/mime.py#line144

Not sure there is a good priority one should follow. Maybe we should check what nautilus or others do, or define the extensions for the most common cases.

[erikos]

Hmm, looks like we should be using globs2:  http://standards.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-latest.html#id2819911

Here some more background:  http://library.gnome.org/admin/system-admin-guide/stable/mimetypes-database.html.en