[launchd-dev] My Launch Agent is Persisting Beyond Logout

[Dave Zarzycki]

"Mac QA",

Does your agent catch Unix signals? Can you please do a "launchctl  
list com.company.mylaunchagent" and email us the results?

Thanks!

davez


On Mar 11, 2008, at 1:41 PM, Mac QA wrote:

> Hi,
>
> I have a custom process that is invoked when a user logs in via having
> a launchd config file located in /Library/Launch Agents. The config
> file looks something like this:
>
> 	<key>KeepAlive</key>
> 	<true/>
> 	<key>Label</key>
> 	<string>com.company.mylaunchagent</string>
> 	<key>OnDemand</key>
> 	<false/>
> 	<key>ProgramArguments</key>
> 	<array>
> 		<string>/mylaunchagent</string>
> 	</array>
> 	<key>RunAtLoad</key>
> 	<true/>
>
> The mylaunchagent is invoked just fine. If I do a fast user switch to
> login another user then a second instance is invoked for the second
> user. All seems good. However, when the second user logs out the
> second instance of mylaunchagent continues to stay running even though
> the user logs out!
>
> The Apple Multiple User Environments document [1] makes two statements
> regarding this. First, "If a user process daemonizes itself prior to
> logout, it can live past the end of the user logout and prolong the
> existence of the login session." And Second, "Per-user services are
> shut down automatically and are not given the chance to abort the
> logout procedure." The mylaunchagent process is always a background
> process just invoked by launchd, so given the first statement I guess
> that is why it is persisting logout. However, given the second
> statement, since this is a per-user service as launchagents are by
> definition, I don't understand why it isn't shut down automatically on
> logout. Frankly, those two statements seem contradictory.
>
> [1] Apple Multiple User Environments
> http://developer.apple.com/documentation/MacOSX/Conceptual/BPMultipleUsers/Concepts/SystemContexts.html#/ 
> /apple_ref/doc/uid/20002208-106206
>
> Can anyone point me towards how to make sure my launch agent processes
> get properly killed when a user logs out? I appreciate any tips.
> Thanks!
> _______________________________________________
> launchd-dev mailing list
> launchd-dev at lists.macosforge.org
> http://lists.macosforge.org/mailman/listinfo.cgi/launchd-dev