[launchd-dev] Book on using launchd?

[Nigel Kersten]

On Fri, May 1, 2009 at 12:45 PM, J.B. Nicholson-Owens <jbn at illinois.edu> wrote:
> Is there a good book or article on using launchd and its future for
> replacing other program-launching programs?  Preferably something with
> examples to illustrate running launchd in the context of a program?
>
> Specifically, I manage multiple labs of Macs all running MacOS X 10.5.6 and
> I'd like to kick off some processes, some as root, some as the user:
>
> - add a link icon to the dock so the user has one-click access to a shared
> SMB volume.  I have been using a Python script to add this dock icon but
> knowing when to run the Python script is tricky; on some machines this works
> perfectly every time, on other machines running MacOS X 10.5.6, the dock
> icon script doesn't run.  I'm guessing I want to run this Python script in
> the dock context but I'm not sure if that's correct.

Are you running this as a LaunchAgent? This should work fine.

>
> - will launchd replace login/logout scripts run as root?  I'd like to clear
> the print queues on the machine (using CUPS' "cancel -a" run as root) when
> the user logs out.  I'd like to do this without prompting the user for admin
> credentials (which our users don't have); print jobs left at logout time
> should simply be cancelled/deleted.

I'd argue you should be using login/logout hooks for this instead of launchd.

>
> - some programs don't take preference settings via MCX (Adobe CS3's Acrobat,
> for instance) and I'll need to set certain preferences for the user every
> time they login via a script (turning off Adobe Acrobat's Javascript, for
> example).

Again, sounds like a LaunchAgent should be more than adequate, but
there are other ways to customize the behavior of Adobe apps.

>
> I'm trying to limit running scripts as the user to functions our users would
> like to have done for them, rather than enforcing policy or attempting any
> security setting by running scripts as the user.  It's my hope that by doing
> this the user won't have any incentive to want to disable running those
> scripts.

Ultimately I'm not sure this is the best place for you to ask these questions.

I suggest you'd have better luck on the http://www.macenterprise.org
mailing list, or the Apple client-management list, as these are
generally well solved problems.