[launchd-dev] Working with overrides.plist

[Dean Shavit]

On Sep 3, 2009, at 12:30 PM, Damien Sorresso wrote:

> On Sep 3, 2009, at 9:53 AM, Dean Shavit wrote:
>> OK,
>>
>> I think I figured it out.
>>
>> Here's what I found:
>>
>> so if you're going to be using the override for a launchagent with  
>> specified SessionTypes, you need to specify a different session  
>> type  -  so:
>>
>> sudo launchctl unload -w -S LoginWindow /Library/LaunchAgents/ 
>> com.most.vnc.plist
>>
>> That sets Disabled to true in the overrides.plist
>>
>> However, in Leopard, launchctl allowed specifying *any* sessiontype  
>> in the plist to write the Disabled key
>>
>> so:
>>
>> sudo launchctl unload -w -S Aqua /Library/LaunchAgents/ 
>> com.most.vnc.plist
>>
>> had the same result. However, in Snow Leopard, it generates an  
>> error. This change was not documented, as far as I can tell. Does  
>> anyone think this requires a bug report?
>
>
> You must specify a session when you manipulate any job which has the  
> LimitLoadToSessionType property set. If the session type you specify  
> isn't one of the elements in LimitLoadToSession type, then launchctl  
> won't do anything.

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

>
>
> There is nothing tying modifying the overrides database to the  
> session type you specify.

OK, but evidently the Session Type specified has an impact on whether  
the launchctl command can successfully modify overrides.plist!

> If you've noticed a pattern, it's a result of the underlying  
> implementation.

I suppose, but I would've hoped for some documentation in that area. I  
guess a bug report is a bit late. Hope this helps someone else.



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