[Groff] Suppressing final page break

[Austin]

Hope you'll forgive my first post being a dumb newbie question ... I have 
searched for an answer with no luck so far.

I have a pair of macros that collect text and format it, then output one chunk 
per page, for printing envelopes, labels, etc.  I'm looking for a more elegant 
way of suppressing the final page break to avoid an empty page at the end of 
the document.  Currently I set a 'first time through' flag and then output the 
page break depending on its value, but this seems slightly kludgy.  Is there 
perhaps a way of making the .bp 'conditional', i.e. only actioned if there is 
text following it?  Or perhaps a way to 'suck it back' in an end-of-input 
macro?  What's the preferred approach (if there is one)?