[launchd-dev] Install and load a launch daemon without a reboot

[Iceberg-Dev]

On Jan 25, 2011, at 7:33 PM, Jeremy Reichman wrote:

> What is considered the current best practice for installing and then
> running a launch daemon, while avoiding a reboot? I didn't see exactly
> what I was looking for in my list archive or found it in any  
> documentation
> on installation packages.
>
> I have reviewed TN2083, specifically the "Starting a Daemon"  
> section. That
> answers most of my question but it would be helpful to have  
> confirmation.
> Besides the conditions listed in TN2083, I'd like my installer to  
> behave
> well when installed to a disk other than the current startup volume. I
> need to target Mac OS X 10.5 and 10.6.
>
> It looks as if I'd need to test for the right conditions and then run
> launchctl to load the property list. Roughly -- not production code  
> -- it
> looks like I'd need a postinstall and postupgrade script to do the
> following:
>
> # Test if the destination volume for the payload and the root  
> volume path
> are the same
> if [ "$3" = "$4" ] ; then
>     # Quick test to see if the script is run by root
>     if [ `/usr/bin/whoami` = "root" ] ; then
>         /bin/launchctl load
> "$3/Library/LaunchDaemons/com.vendor.launchdaemon.plist"
>     fi
> fi
> exit 0
>
> Is that the right approach? Thanks!

By payload, do you mean an installation package payload?

If so, then you need to require root/admin authentication in the  
installation package (to be able to install stuff in /Library/ 
LaunchDaemons/.

And you don't need both a postinstall and postupgrade scripts. A  
postflight script is enough if you're using a bundle package. A  
postinstall script is OK if you are using a flat package.

You don't need to use whoami. Just use sudo before /bin/launchctl.