how to use compiled .so in C++

[gnasen]

Hello folks,

I'm pretty new to programming in c++ and ran into the following problem:
I want to etablish a network connection between a windows and a linux system and use the pb network lib for this task.
However if I try to compile a simple .so lib like this

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ProcedureCDLL.i go()
  MessageRequester("test","hello")
EndProcedure

and save it as libtest.so I dont find a solution to use it in my c++ code. I added it to the linker (Makefile) with "-ltest", but now I have no idea how to go on.
Normally Ive got some .H file to include...

Help..

[gnasen]

I got it working with this code in the main part:

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void *handle;
handle = dlopen ("mypath/mylib.so", RTLD_LAZY);
void (*go)();
*(void **)(&go) = dlsym(handle, "go");
go();
dlclose(handle);

However I dont understand why I need to call dlsym with this *(void **) prefix. I dont even understand what it should mean. dlsym should in my opinion return a pointer to the function, why can I not retrieve it with this:

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void (*go)();
go = dlsym(handle, "go");

This confuses me..

[Fred]

You only defined a new type, try this (not tested but it should work):

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void (*go_type)();
go_type go;

go = dlsym(handle, "go");
go();

[gnasen]

Thank you very much, it pointed me to the right direction, it works now like this:

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typedef int (*go_type)();
go_type go;
go = (go_type)dlsym(handle, "go");
go();

Still I dont get all that pointer mess in c++. I have still no idea how to read this *(void **)(&go). It makes c very hard to learn if such stuff is used in tutorials and not really explained. Im still looking for a good book (not expert level) where I could find an explenation for this kind of stuff..