r.external - was: Re: [GRASS-dev] some questions about future development

[Markus Neteler]

On Wed, Aug 20, 2008 at 3:46 PM, Glynn Clements
<glynn at gclements.plus.com> wrote:
> Markus Neteler wrote:
>
>> this is excellent! Thanks so much. I have tested it but no success yet:
>
>> >> Tomorrow, I'll look into creating an r.external module, adding null
>> >> support, etc.
>> >
>> > Okay, done (well, enough to try it out without having to manually hack
>> > the files; null support is absent).
>>
>> [for my convenience I have copied it over to GRASS 6.4.svn locally]
>
> Copied what over? r.external won't work unless the corresponding
> lib/gis changes have also been incorporated, and lib/gis was built
> with GDAL_LINK=1:
>
>> At present, r.external is built automatically, but the code to read
>> linked maps is conditionalised upon GDAL_LINK, so you need to build
>> with "make GDAL_LINK=1". If you forget that part, r.external will
>> work, but attempting to read the map will fail (the cell/fcell files
>> are zero-length).

Bingo. I overlooked the GDAL_LINK thing.

> Your errors are consistent with lib/gis not having the necessary
> support.

Right.

Now r.stats works! Will try to (locally) backport to 6.4 now (for
monitor tests).

Thanks again,
Markus

PS: Small issue:

gcc -I/home/neteler/grass70/dist.x86_64-unknown-linux-gnu/include  -g
-Wall  -fno-common -mtune=nocona -m64 -minline-all-stringops    -fPIC
-D_FILE_OFFSET_BITS=64 -DGDAL_LINK   -DPACKAGE=\""grasslibs"\"
-I/usr/local/include -I/usr/local/include
-I/home/neteler/grass70/dist.x86_64-unknown-linux-gnu/include -o
OBJ.x86_64-unknown-linux-gnu/quant.o -c quant.c
quant.c:293:1: warning: "MIN" redefined
In file included from /usr/local/include/gdal.h:40,
                 from
/home/neteler/grass70/dist.x86_64-unknown-linux-gnu/include/grass/gis.h:32,
                 from quant.c:286:
/usr/local/include/cpl_port.h:257:1: warning: this is the location of
the previous definition
quant.c:294:1: warning: "MAX" redefined
/usr/local/include/cpl_port.h:258:1: warning: this is the location of
the previous definition