Simple Plist. No output. What gives?

Question

I'm trying find exactly what's wrong with a larger job that I'm trying to schedule with launchd for the first time. So I made the simplest python file I could think of, print 'running test', titled it com.schedulertest.plist and then made a plist file like so:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC -//Apple Computer//DTD PLIST 1.0//EN http://www.apple.com/DTDs/PropertyList-1.0.dtd >
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.schedulertest.py.plist</string>
    <key>ProgramArguments</key>
    <array>
        <string>arch</string>
        <string>-i386</string>
        <string>/usr/bin/python2.7</string>
        <string>/Users/user/Documents/Python_Alerts_Project/schedulertest.py</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>StartInterval</key>
    <integer>60</integer>
</dict>
</plist>

Then I saved it in $HOME/Library/LaunchAgents/ and ran:

launchctl load com.schedulertest.plist

I should be getting the print output from my py script every 60 seconds, right? I don't see anything though -- is there an obvious fault in my script or process?

Answer 1

So the answer was not a big deal, but it might help others to share the solution. I had simply forgotten, as we will when moving around several virtualenvs, which python I was in. If you're having trouble and your .plist and script seem well-formed, it won't hurt to run which python etc, and check the result against the path you're listing in your program arguments.

Answer 2

Troubleshooting

• To debug .plist, you can check the log for any error, e.g.

  tail -f /var/log/system.log
  

  To specify custom log, use:

  <key>StandardOutPath</key>
  <string>/var/log/myjob.log</string>
  <key>StandardErrorPath</key>
  <string>/var/log/myjob.log</string>
  

• To find the latest exit status of the job, run:

  launchctl list com.schedulertest.plist
  

• To make sure the syntax is correct, use plutil command.

See: Debugging launchd Jobs section of Creating Launch Daemons and Agents page.