[GRASS-dev] RE: [GRASS-user] Question with Python-SWIG example [SEC=UNCLASSIFIED]

[Martin Landa]

Hi,

2010/5/24 Glynn Clements <glynn at gclements.plus.com>:
> G_find_raster2 is (or should be) defined in grass.py as:
>
>        # /usr/local/src/grass/7.0/dist.i686-pc-linux-gnu/include/grass/gisdefs.h: 220
>        if hasattr(_libs['grass_gis'], 'G_find_raster2'):
>            G_find_raster2 = _libs['grass_gis'].G_find_raster2
>            G_find_raster2.restype = ReturnString
>            G_find_raster2.argtypes = [String, String]

I have ...

lib/python/ctypes/grass.py:if hasattr(_libs['grass_gis'], 'G_find_raster2'):
lib/python/ctypes/grass.py:    G_find_raster2 =
_libs['grass_gis'].G_find_raster2
lib/python/ctypes/grass.py:    G_find_raster2.restype = String
lib/python/ctypes/grass.py:    G_find_raster2.argtypes = [String, String]
lib/python/ctypes/grass.py:    G_find_raster2.errcheck = ReturnString

> The only imports in grass.py are:
>
>        from ctypes_preamble import *
>        from ctypes_preamble import _variadic_function
>        from ctypes_loader import *
>
> so it shouldn't be possible for it to pick up some other definition
> for "String".
>
> It's annoying that the error message doesn't indicate which class's
> __init__ method is involved, or  the traceback.
>
> Some other things to check:
>
>        > from grass.lib import grass
>        > grass.String
>        <class 'ctypes.c_char_p'>

<class 'ctypes.c_char_p'>

>        > grass.ReturnString
>        <class 'ctypes.c_char_p'>

<class 'ctypes.c_char_p'>

>        > grass.G_find_raster2
>        <_FuncPtr object at 0x827eecc>

<_FuncPtr object at 0xb7038b24>

>        > grass.G_find_raster2.__class__
>        <class 'ctypes._FuncPtr'>

<class 'ctypes._FuncPtr'>

>        > grass.G_find_raster2.argtypes
>        [<class 'ctypes.c_char_p'>, <class 'ctypes.c_char_p'>]

[<class 'ctypes.c_char_p'>, <class 'ctypes.c_char_p'>]

>        > grass.G_find_raster2.restype
>        <class 'ctypes.c_char_p'>

<class 'ctypes.c_char_p'>

>        > grass.G_find_raster2._restype_
>        <class 'ctypes.c_long'>

<class 'ctypes.c_long'>

>        > grass.G_find_raster2._objects
>        {'0': <CDLL '/usr/local/src/grass/svn/dist.i686-pc-linux-gnu/lib/libgrass_gis.so', handle 8193e88 at 824f32c>}
>

{'0': <CDLL '/usr/local/src/grass_trunk/dist.i686-pc-linux-gnu/lib/libgrass_gis.so',
handle 9b01180 at b711f06c>}


Martin

-- 
Martin Landa <landa.martin gmail.com> * http://gama.fsv.cvut.cz/~landa