Am 03.04.2008 um 08:30 schrieb Quinn <eskimo1@apple.com>:

At 10:20 +0100 2/4/08, Quinn wrote:

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At 17:05 +0200 1/4/08, Mike Fischer wrote:

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So "unload" makes launchd completely forget about a service while "load" does the reverse?

Right.

OK, that's was a little more succinct that I originally intended.

:-) Would have helped on it's own though. I was just making sure I understood because some experiments I did with a custom Launch Agent to create a system profile report once per day (for having it handy when filing bug reports) seemed to make it necessary to logout/login to make it work. I tried unload/load (I think) without success but I didn't document my exact steps to get it to work. I'll just mark this off as experimenting with too many unknown variables and too little knowledge. The Launch Agent now works btw.

Here's some more background:

This one super-confusing part of launchd if you're coming to it from scratch. The lifecycle of a job is:

load -> start -> stop -> [...] -> unload

The load can be done implicitly (typically at the start of a session, for example, at startup time launchd loads all of the enabled jobs in /System/Library/LaunchDaemons) or explicitly (via "launchctl load"). Unloads, per se, only happen explicitly (via "launchctl unload"), but jobs are effectively unloaded if the session that they're loaded into dies (keep in mind that launchd's global session never dies).

Similarly, the start can be done implicitly (via the RunAtLoad property, or by meeting one of your the launch-on-demand criteria, or by the KeepAlive property) or explicitly (via "launchctl start"). And a stop happens when the job quits or, explicitly, via "launchctl stop".

Thanks for the very clear explanation. Mike -- Mike Fischer Softwareentwicklung, EDV-Beratung Schulung, Vertrieb Note: I read this list in digest mode! Send me a private copy for faster responses.