There's something in the old FAQ about this:
http://www.cecer.army.mil/grass/faqtxt1.html#mm
In addition, I ran across a potential problem in v.in.dxf
where it looks like the date recorded might get truncated
because the diglib used date[20] in the dig_header, but the
G_date function is used to assign a value to this in v.in.dxf.
G_date returns a pointer to whatever your system returns in
asctime(), which might be greater than 20 chars. I'd
suggest writing a G_date2 or something that gets a formatted
date with just 3_char_month, day, 4digit_year so it would always be
less than 20 chars. Then use G_date2 to get the date for v.in.dxf.
That's the only program I saw like that - most vector programs
seemed to use V_ask, like v.digit only asked for month & year. But
if you've written vector programs, you might check this.
- Bill