Programming vector attributes

[Philip Verhagen, Stichting RAAP]

A question about GRASS-programming:

I am trying to get into using GRASS source code to make some specific
programs for my own use. The first one I made is a program that makes
vector buffers around sites (circles of a user-specified dimension).
This works allright, but the trouble starts when I try to give an
attribute value to the newly created lines. Is there a standard routine
you can use to give an attribute value to a line or area? The routines
provided in the GRASS3.0 Programmer's Manual only retrieve attributes,
they can't change them.

Any help would be appreciated!

Philip Verhagen.