Keep an installation alive with launchd & launchctl

README.txt

Add this .plist to ~/Library/LaunchAgents to have it automatically
take effect whenever you log in. It will continue to be active until
you log out (even if you delete the file).

You can take manual control over it instead by putting the file 
anywhere else, then using launchctl like this:

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launchctl load path/to/the/plist/com.admsyn.keep-twitter-alive.plist
- - - - - - - - - - - - - - - - - - - - - - - - - - - - 

and

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launchctl unload path/to/the/plist/com.admsyn.keep-twitter-alive.plist
- - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Some notes :

- It will keep itself from rebooting the app repeatedly over a short
  period of time (e.g. if it crashes it will reboot instantly, if it
  crashes again right away it'll wait ~10 secs before trying again). 
  I believe this is adjustable with another param in the plist.

- launchd "owns" the app it spawns this way, so if you open the app
  yourself, then load the .plist, you'll get two copies of the app running.

- Make sure the "Program" arg in the .plist points to the actual 
  executable (e.g. in Contents/MacOS) instead of just the .app

com.admsyn.keep-twitter-alive.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>KeepAlive</key>
	<true/>
	<key>Label</key>
	<string>com.admsyn.keep-twitter-alive</string>
	<key>Program</key>
	<string>/Applications/Twitter.app/Contents/MacOS/Twitter</string>
</dict>
</plist>

thanks a ton, this is perfect.

This is great, thanks! I'd like to add that if anyone is running into issues where their application performs noticable worse when launched using launchd, it may help to set the ProcessType tag to Interactive:

<key>ProcessType</key>
<string>Interactive</string>