From: Joel VanderWerf <vjoel@...>
Date: 2004-08-19T07:28:49+09:00
Subject: Re: swig problem with init

jim@freeze.org wrote:
> I have an innocuous swig/ruby case that is causing me some grief.
> The problem is probably obvious, but I'm not seeing the solution
> right now.
> 
> I have a .i file that defines a module 
> 
>      cat itkdb.i
>     /* itkdb.i */
>     %module ITKDb
> 
>     %{
>     %}
> 
> This generates a wrapper with the following lines of interest:
> 
>     #define SWIG_init    Init_ITKDb
>     #define SWIG_name    "ITKDb"
> 
>     #ifdef __cplusplus
>     extern "C"
>     #endif
>     SWIGEXPORT(void) Init_ITKDb(void) {
>         int i;
> 
>         SWIG_InitRuntime();
>         mITKDb = rb_define_module("ITKDb");
> 
>         for (i = 0; swig_types_initial[i]; i++) {
>             swig_types[i] = SWIG_TypeRegister(swig_types_initial[i]);
>             SWIG_define_class(swig_types[i]);
>         }
> 
>     }
> 
> I compile this against a vendor supplied library and try to load the .so
> file and get:
> 
>     ruby -r itkdb -e {}
>     ./itkdb.so: /usr/lib/libruby.so.1.8: undefined symbol: Init_itkdb -
>     ./itkdb.so (LoadError)
> 
> Can someone tell me what I'm doing wrong here?

Ruby's loader looks for init_<filename> in filename.so. So if you

   mv itkdb.so ITKDb.so

it may work.