You can use r.mapcalc script
To check if the cell has a value, if it does then do nothing. If it
does
not have a value then assign it the neighboring value. You may run the
mapcalc script as many times as you wish to filter out the holes.
Thanks, I received a message from Susan Huse. She said that I can modify
my input vector file and turn off the labels on the lines. In this way,
when I run the v.in.rast command, lines will be ignored. I will like to
play with r.mapcalc. It sounds very similar to ARC INFO grid algebra
that
I enjoyed working with.
Marlin Mixon