[Mediawiki-l] How does wfDebug work?

[Rick DeNatale]

I'm trying to debug an extension. I found the wfDebug function which
seems to be widely used in the rest of the mediawiki code, but I can't
seem to get it to do anything. I know that I'm running through at
least one wfDebug() call but it seems to have no effect.

I've set $wgDebugLogFile to the path of a file and made sure that the
web server has write access to it. I don't get any output.  I then set
$wgDebugComments to true but still no output.

Is there something I'm missing?