[launchd-dev] Agent started two different was, two different bootstraps?

James Bucanek subscriber at gloaming.com
Fri Jan 25 13:31:27 PST 2008

Dave Zarzycki <mailto:zarzycki at apple.com> wrote (Friday, January 
25, 2008 12:13 PM -0800):
>-S, not -s, but otherwise, that is probably the solution.

Dave, Hamish,

That seems to be the problem.

If I load the agent using

     launchctl load com.qrecall.monitor.plist

it doesn't work. It runs, but can't connect to any processes 
using Mach ports.

If I unload it and reload it using

     launchctl load -S Aqua com.qrecall.monitor.plist

it works! It connects and communicate just fine.

As an experiment, I added


to the plist and tried to load it again, with and without 
specifying the sessiontype. Here's what I got:

     crocodile:LaunchAgents james$ launchctl load com.qrecall.monitor.plist
     nothing found to load

     crocodile:LaunchAgents james$ launchctl load -S Aqua com.qrecall.monitor.plist
     crocodile:LaunchAgents james$

So it appears issuing "launchctl load" as a user process is 
assuming some other kind of sessiontype.

So I think there's definitely a bug here, although it's not the 
more overt bug I thought it was.

1) As Hamish pointed out, LimitLoadToSessionType defaults to 
Aqua. So in the absence of LimitLoadToSessionType, an agent 
should only be loaded in the Aqua bootstrap/sessiontype.

2) If you include the LimitLoadToSessionType=Aqua in the plist, 
'launchctl load' ignores the plist with "nothing to load." I now 
realize that it's because the session types are different.

3) If you omit the LimitLoadToSessionType in the plist, 
'launchctl load' loads the agent in whatever sessiontype it 
defaults to, which is in contradiction to (1).

If this sounds reasonable, I'll file a bug report.

In the meantime I'll add -S Aqua to my initial load command.

James Bucanek

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