Debugging Tip

[Arcticus]

Here is a quick debugging tip to look for syntax and other errors. SSH into the emulator and navigate to "root@qemux86:/var/log" then do "vi messages" and scroll to the end using page down. This is the emulators error log, I believe you also need to set your "logLevel": "99" in your appinfo.json file.

Just in case to exit vi type ':' then 'q' 'enter'

Also this is not a dynamic log you will need to quit and reopen to see updates as you run your app.

[Trano]

To see a dynamic update of the log you can do:

tail -f /var/log/messages

This will keep show you all the updates as they are written to the log. I've been using this and it has helped out a lot.

[sbc]

Debugging has been killing me. Can we make this the "Official" Debugging Tips thread. Are there any others tips out there?

Is debugging easier with a rooted Pre vs just using the emulator? (Any such thing as a rooted emulator?)

How are folks debugging "white screens"?

[Trano]

The emulator is already rooted and has ssh listening on port 5522. You have to connect to that to run the command I mentioned before. I find it easier to debug on the emulator, but that is just my opinion.

As far as the "white screen", I only encountered this once and it was because of a syntax error in my javascript. I was able to debug it by looking at the messages log which told me that it was a syntax error and which line it was on.

[schoksi]

for anyone reading, in case you're a complete rookie to the terminal like me the command to SSH into the terminal is:

ssh -p 5522 root@localhost

from: pre dev wiki: Enable Root Access

thanks for this thread guys, makes debugging much easier