[GRASS-dev] QGIS winGRASS blank space problem

[Paul Kelly]

Hello Markus

On Mon, 4 Jun 2007, Markus Neteler wrote:

> Hi,
>
> a friend told me that with the latest QGIS release candidate,
> there is a winGRASS problem:
>
> $ v.rast.stats vector=CEA_riserve raster=CEA_slope colprefix=delete
> c:/Programmi/Quantum: c:/Programmi/Quantum: No such file or directory

v.rast.stats is a shell script, so you are likely to have loads of 
problems if not finding it nearly impossible to get it working properly on 
Windows. I notice there are loads of places in it that paths aren't 
quoted so that is probably the first problem (although to be fair that is 
also a problem for Unix and isn't a problem for Windows if you don't 
install software in paths with spaces in them!).

Then there is the fact that Msys doesn't understand Windows-style paths, 
but the output from g.tempfile will be a Windows-style path. (A question 
for another day: perhaps we could investigate other bourne-compatible 
shells for Windows that *do* understand Windows paths? But some GRASS 
scripts would probably need to be changed in other ways to be compatible 
with that; maybe more effort than it's worth.)

Another thing is that v.rast.stats attempts to call v.db.addcol and fails 
- it's also a script, so on Windows is represented by the file 
v.db.addcol.bat - apparently Msys's shell can't run .bat files. That's 
actually something I didn't forsee when implementing the .bat 
script-launching mechanism for Windows. You could probably work around it 
by putting in the full path ($GISBASE/scripts) before calling another 
script from a script, but then you still have the issue with incompatible 
path names as I mentioned above.

In general it's a pleasant surprise if some shell scripts to happen to 
work OK on Windows, and IMHO shouldn't really be considered a bug if they 
don't. I feel the fact that QGIS includes a copy of Msys with GRASS gives 
the "illusion" of GRASS being more compatible with Windows than it really 
is - the truly native WinGRASS we're working on is a more accurate 
expression of GRASS's compatiblity with Windows as I see it.

Paul