[GRASS-user] Clipping shapefiles

[Matthew Huck]

Hi,
   I'm trying to clip a largeish shapefile (100Mb) containing contour  
lines of a reasonably hilly area, into an area that is about 1/12 of  
it.  I'm finding v.overlay very slow (in excess of 17 hours on a quad  
core 4GB Windows machine), am I doing something wrong?

g.region vect=NZMG_s27
v.in.region output=cutter type=line --overwrite
v.overlay ainput=wellington_contours atype=line binput=cutter  
output=clipped operator=and

I'm using GRASS 6.3 (both on Windows Vista 64 (but as a 32 bit exe),  
and on Mac OSX

Thanks in advance

Matthew