View source for GRASS and windows console

''This page shows extended examples how to run GRASS modules in the winGRASS windows console''

==Windows batch files in GRASS==

In order to ease the workflow of analysis, several GRASS modules can be invoked at once by an batch file (*.bat) in the winGRASS windows console.

[https://trac.osgeo.org/grass/browser/grass/trunk/scripts Python grass modules] (e.g. v.db.addcolumn) have to be invoked by ''call'' in the batch-file.

<source lang="bat">
@ECHO ON
g.region -p
v.in.region output=myreg
call v.db.addtable map=myreg
call v.db.addcolumn map=myreg columns="col1 double"
v.to.db map=myreg option=area columns=col1
</source>

Running batch files without starting up GRASS:

<source lang="bat">
"%ProgramFiles?%\QGIS 2.18\bin\Grass72.bat" --exec MyScript.bat D:/myGrassData/MyLoc/MyMapset 
</source>

==g.list output as input for another GRASS module==

Using g.list output as input variable for another module, e.g. to remove a list raster map.

<source lang="bat">
FOR /F %c in ('g.list "type=raster" "pattern=*2" "mapset=user1" "separator=comma"') DO SET RASTER2REMOVE=%c

echo %RASTER2REMOVE%
b172,d172,it172,r172

g.remove type=raster name=%RASTER2REMOVE%
The following data base element files would be deleted:
raster/b172@user1
raster/d172@user1
raster/it172@user1
raster/r172@user1
WARNING: Nothing removed. You must use the force flag (-f) to actually
         remove them. Exiting. 
</source>

Using g.list output as input variable for another module, e.g. to loop through a list of vector maps and buffer them.

<source lang="bat">
FOR /F %c IN ('g.list "type=vector" "separator=comma"') DO SET VECTLIST=%c

FOR %g IN (%VECTLIST%) DO v.buffer input=%g output=%g_buffer_200 distance=200
</source>

== selecting a shell ==
On MS Windows, in the absence of the environmental variable GRASS_SH, the grass startup script selects the shell specified in environment variable ComSpec.  This is typically cmd.exe.

<source lang="bat">
REM check shell
echo %ComSpec%
C:\WINDOWS\system32\cmd.exe
</source>

The default shell can be overridden by setting the environment variable GRASS_SH. To make powershell the startup command shell set the environment variable with
<source lang="bat">
SET GRASS_SH=%SystemRoot%\system32\WindowsPowerShell\v1.0\powershell.exe
</source>

[[Category: Development]]
[[Category: FAQ]]
[[Category: WinGRASS]]