how to setup a revolving credit facility account

[David Latham]

Dear list,

I have just subscribed to this list,  So please bear with me. 

I was wondering how one sets up GNU Cash to deal with a revolving credit
loan.  This loan should act as both a liability account AND a current
checking account.  Any transactions to the checking account should be
transferred to the appropriate income / expense account AS WELL as being
inversely linked to the loan account.

Basically any income immediately reduces the loan and any payments
immediately increase the loan.

At the same time I wish to use the features of the checking account and
double entry to accounts such as salary or groceries in the normal
manner.

This would be a "deal breaker" for me.  IF I can get this working, I
basically cant use gnu cash.   Which would be a shame because I like the
software a lot.

Thanks for your time,

Dave Latham