name of a column returned from a table function

DB Version 7,4.

I had a look through the docs, but the information on table functions (those
returning SETOF something) seems to have gone missing from the 7.4 docs. I
found something under 7.3, but it didn't answer my question, which is...

I've written a little table function that simply returns all the dates in a
month. No problems so far. Now I want to outer join this list to another
table, but I dont know what to call the column returned by the function. All
the examples I saw just had "select * from <fnname>".

I want do something like "select <fnsdatecolname>,... from <myfn> join
<atable> on (<fnsdatecolname> = <atablesdatecolname>;

Searching the lists, I found something to the effect that this might have
problems. Is that still the case?

Thanks
Iain