How to determining why an Erlang application is not starting?

Question

I'm trying to start an Erlang app that is failing. All I see in the shell is:

=INFO REPORT==== 7-Jan-2010::17:37:42 ===
    application: ui
    exited: {shutdown,{ui_app,start,[normal,[]]}}
    type: temporary

How can I get Erlang to give me more information as to why the application is not starting? There currently is no other output in the shell.

Answer 1

You could try launching the shell with more logging support:

erl -boot start_sasl

this might get give a bit more details.

Answer 2

It is a pain, but the way I do it is the old fashioned way, by writing io:format's into the start function of the application (ie the code of the module with the behaviour of application) and working out which line fails :(

Sometimes brute force and ignorance is your only man...