[gdal-dev] Re: VRT Derived Bands from Python?

[Antonio Valentino]

Hi Even, hi Knut-Frode,

Il 13/05/2011 19:07, Even Rouault ha scritto:
> Le vendredi 13 mai 2011 18:59:14, Knut-Frode Dagestad a écrit :
>> On 13/05/2011 12:07, Antonio Valentino wrote:
>>> If you think it is useful I can attach the fake-driver code to the
>>> #3367.
>>
>> Thank you, that would be useful.

Now the code is at

http://trac.osgeo.org/gdal/attachment/ticket/3367/pixfun-plugin-20110513.tar.gz

>> In the meantime I have tested this approach, nearly successful:
>> I copied one of your pixel-functions from #3367 and made a dynamic
>> library file with:
>>
>> gcc -fPIC -c gdal_nerscpixelfun.c
>> gcc -shared -lgdal -o gdal_nerscpixelfun.so gdal_nerscpixelfun.o
>>
>> and then set GDAL_DRIVER_PATH to point to this folder.
>>
>> However, at GDAL startup I get the following error:
>> ERROR 1: dlsym(0x100e095f0, _GDALRegister_nerscpixelfun): symbol not found
> 
> I had also a similar error on Linux, but it worked despite the error. I have 
> pushed a fix in trunk to silent that error. You can try to add a printf() 
> statement in your GDALRegisterMe function to check if it is loaded correctly.
> 
> Explanation : GDAL tries to load first a symbol called GDALRegister_xxxxx when 
> the .so is called gdal_xxxxxx.so/dll, and if not present it then tries 
> GDALRegisterMe. There's no point emitting an error if GDALRegister_xxxxx is 
> not found, but GDALRegisterMe is found. See 
> http://trac.osgeo.org/gdal/changeset/22359

I just used GDALRegister_PIXFUN. There is some difference?

ciao

-- 
Antonio Valentino