file date function?

[David Ronis <ronis ronispc chem mcgill ca>]

I use gnumeric to generate several reports, based on other spreadsheets 
that I combine into a single gnumeric file.
I'd like to have the report automatically have the date the file was 
modified showing (e.g., like today(), but for the filename).

I don't seem to see anything that fits the bill in the list of 
functions.  Did I miss it?  If not, it should be easy to add.

David

P.S., I'm not a subscriber, and would appreciate a CC of any reply.