[This applies to GRASS 5.0.x; use v.in.ogr in GRASS >= 5.7]
Currently there is only a "quick-and-dirty" way to import ESRI's vector shape files into GRASS GIS:
1. Convert the SHAPE file to UNGENERATE format:
Example: v.shp2gen roads.shp > roads.lin
2. Convert the attributes:
Example: v.dbfdump roads.dbf > roads.txt
3. Create an arc-subdirectory in the location:
mkdir $LOCATION/arc
4. Move the new files to this place:
Example: cp roads.lin roads.txt $LOCATION/arc
5. Import the files into GRASS:
v.in.arcFollow the instructions within the file...
6. Create the support file:
Example: v.support map=roads