[Pythonmac-SIG] associating file types and applications...
bob at redivi.com
Thu Apr 1 12:53:00 EST 2004
On Apr 1, 2004, at 12:43 PM, Tom Pollard wrote:
> On Apr 1, 2004, at 2:38 AM, Jens Miltner wrote:
>>>> The default app to use when opening a document is a property of the
>>>> Finder. Users can always reassign particular document types to the
>>>> app of their choosing using the Info window. So, I'm not sure it
>>>> would be considered "playing nice" to override that preference for
>>>> an existing filetype. I imagine if you introduce a new filetype,
>>>> your app will automatically be the default app for opening those
>>>> files. That's just my impression of how things work - I'm not an
>>> There *is* a way to do this, though: the various media players
>>> (quicktime, itunes, realplayer, windows media) all offer to handle
>>> all your mp3s and other types for you, and if you say "yes" they do
>>> it (at least until you override again from the finder).
>>> I'm not sure whether they do this through AppleEvents to the Finder,
>>> AppleEvents to something else or a completely different mechanism,
>> AFAIK, this is still done is through InternetConfig (even though that
>> API is kind of deprecated) - you should be able to set the default
>> "helper app" for a file type / mime type using the InternetConfig
> I don't know how to change the filetype/application association from
> the command line, but I did find that this information is kept in the
> LaunchServices property list
> (~/Library/Preferences/com.apple.LaunchServices.plist). You can
> browse this file by opening it in with the Property List Editor. It's
> just an XML file, so you can open it in a text editor, too. You can
> dump its contents to the terminal in more readble form by saying
> % defaults read com.apple.LaunchServices
> For simpler plists, the 'defaults' command would also let you change
> property values from the command line, but in this case that doesn't
> work, because 'defaults' only acts on top-level properties.
> LaunchServices has only a single top-level property,
> "LSPrefsBindings", a dictionary that associates filetypes with
> application bundles. Also, application bundles are identified using
> more that just a path to the application, but a small dictionary of
> information, including a binary "LSBundleLocator" that may be an
> alias, or something like that.
> There are some command-line apps included with the LaunchServices
> framework, in
> but none of these looks like a tool for changing filetype/application
> I imagine poking around the Developer documentation on the ADC site
> would reveal a programmatic way of interacting with LaunchServices to
> change the associations...
From what I remember, I'm pretty sure LaunchServices does NOT offer
that functionality to the developer. If it does, it's new with 10.3.
The LaunchServices database is mostly a black box.
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