[launchd-dev] Working with overrides.plist

[Dean Shavit]

On Sep 3, 2009, at 1:02 PM, Damien Sorresso wrote:

> On Sep 3, 2009, at 10:37 AM, Dean Shavit wrote:
>> I am aware of that. But there's differences in behavior. In  
>> Leopard, specifying any Session Type listed in the LaunchAgent  
>> using "sudo" worked to write the Disable key in the plist targeted.  
>> In Snow Leopard, this behavior does not hold true for the  
>> overrides.plist
>
> I'd argue that the Leopard behavior was improper. Asking to modify a  
> job in a  session where it cannot exist should be a no-op.

Agreed that the Leopard behavior was improper. However, since the  
"proper" behavior was not documented, and still isn't, I would argue  
that the launchctl man page needs some concrete examples and  
explanation of the proper behavior - it is really thin, and apropos  
shows no mention of "overrides.plist" anyway.

My LaunchAgent contains *two* Session Types - Aqua and LoginWindow,  
just like com.apple.RemoteDesktop.plist

If the "correct" behavior is to limit the unload/load behavior to  
"active" or "existable" Session Types, you should say so in the man  
page. Since it worked in Leopard, I made the incorrect assumption it  
would carry over to Snow Leopard.

If you wish, I will *volunteer* to expand the man page with some more  
examples for the next release of Mac OS X. Just send me the NDA, and  
I'm your man-scribe for the next two years....



>
>
> In any case, we really hope to clean up the mess of sessions post- 
> Snow Leopard. We also just want to get rid of the Disabled key  
> entirely.

OK, go ahead, get rid of the key, but please leave some sort of  
mechanism for sysadmins or developers to disable a LaunchAgent via an  
override mechanism so long as they can sudo as root.


I also personally feel that once the override is applied, no logout  
should be required to unload a currently running instance of the  
LaunchAgent in quesiton - the override should automatically unload the  
LaunchAgent for currently logged in users and terminate any processes  
they've spawned. As it is, we have a lot of manual cleanup to do if we  
want to stop one without a logout.

  Also, while we're on the subject of post-Snow Leopard, please  
consider implementing group, user, and computer-level management of  
LaunchAgents via MCX.


>
> -- 
> Damien Sorresso
> BSD Engineering
> Apple Inc.
>