[GRASS5] v.category output=: required or not?

[Hamish]

v.category has [output=map] as optional, yet if you leave it out you get
an error.

I expect if not given v.category should try and update existing vector?

task:
I have made a new vector lines map with 'v.distance out=' and have to
give features a cat number before giving it a table to upload lengths
into (v.to.db) for v.univar.sh analysis.

optional-but-broken or shouldn't-be-optional?


Hamish