Seb:
> I'm trying to import several hundred rasters from GMT into GRASS,
> and the only way I managed to do it was by piping grd2xyz output
> through r.in.xyz,
oh, besides the GMT wiki page[1] see also this wiki page[2] which
gives an example of grd2xyz | r.in.xyz.
[1] http://grass.osgeo.org/wiki/GRASS_and_GMT
[2] http://grass.osgeo.org/wiki/Marine_Science#Bathymetric_data
please fix directly or point out any errors or inefficiencies you find.
Hamish