[MEncoder-users] config file - location and syntax?

[how dou]

Can someone give me the details on how the mencoder config file works?
 I found 3 year old info in the archives calling out a
'/etc/mencoder.conf', but that did not work.  I then stumbled across
an archive that mentioned, indirectly, a '~/.mplayer/mencoder'.  This
location seems to work (I get errors/warnings referring to a config
problem), but I cannot guess the required syntax.  I tried the method
stated in /etc/mplayer.conf (tv=driver=v4l2:width=...) but that did
not work.  I also tried some other guesses as to the syntax, but they
failed also.

I thought it best to not waste time guessing and get the lowdown from
the experts/veterans.  So, what is the official location (if
locations, what's the precedence) and syntax for a mencoder config
file?  And, why isn't this spelled out in the manual?

TIA!