There are times when you will need to load a LaunchAgent when a script is running as root - when you are running a postinstall script from a package or when you are loading the LaunchAgent via your management tool of choice (Puppet, Munki, Jamf Pro), for example.
All of these example are assuming you have a LaunchAgent at /Library/LaunchAgents/com.company.example.plist.
Loading a LaunchAgent
#!/bin/bash
# get console UID
consoleuser=`/usr/bin/stat -f "%Su" /dev/console | /usr/bin/xargs /usr/bin/id -u`
/bin/launchctl bootstrap gui/$consoleuser /Library/LaunchAgents/com.company.example.plist
#!/usr/bin/python
from pwd import getpwnam
import subprocess
import sys
from SystemConfiguration import SCDynamicStoreCopyConsoleUser
username = (SCDynamicStoreCopyConsoleUser(None, None, None) or [None])[0]
if username is None:
# Exit if there isn't anyone logged in
sys.exit()
uid = getpwnam(username).pw_uid
subprocess.call(['/bin/launchctl', 'bootstrap', 'gui/{}'.format(uid), '/Library/LaunchAgents/com.company.example.plist'])
Unloading a LaunchAgent
#!/bin/bash
# get console UID
consoleuser=`/usr/bin/stat -f "%Su" /dev/console | /usr/bin/xargs /usr/bin/id -u`
/bin/launchctl bootout gui/$consoleuser /Library/LaunchAgents/com.company.example.plist
#!/usr/bin/python
from pwd import getpwnam
import subprocess
import sys
from SystemConfiguration import SCDynamicStoreCopyConsoleUser
username = (SCDynamicStoreCopyConsoleUser(None, None, None) or [None])[0]
if username is None:
# Exit if there isn't anyone logged in
sys.exit()
uid = getpwnam(username).pw_uid
subprocess.call(['/bin/launchctl', 'bootout', 'gui/{}'.format(uid), '/Library/LaunchAgents/com.company.example.plist'])
The Python version may look more complicated, but is slightly more robust as it is retrieving the current username using Apple’s frameworks and I have also allowed for the script not to fail if there isn’t a user logged in.