The reason for SIGSEGV function pointer problem

[Russel Winder via Digitalmars-d-learn]

OK, so I have narrowed down my SIGSEGV problem to having no real idea
how to do C function pointers in D code.

So I have a callback function that will be called from C library code.
It currently has signature:

    extern(C) int checkFrontend(void* _arguments, dvb_v5_fe_parms* frontendParameters)
 
because of the extern(C) I believe you have to use a type alias in
order to specify the type in function definitions. Hence:

    alias check_frontend_t = extern(C) int function (void* args, dvb_v5_fe_parms* parms);

In the constructor of an object to abstract the result of a call to the
C library code, the parameter is:

    check_frontend_t* cf

in the creation of the object using the constructor, I am using the
argument:

    &checkFrontend

However. This gives me a type error:

    extern (C) int function(void*, dvb_v5_fe_parms*)* cf

is not callable using argument type:

    extern (C) int function(void*, dvb_v5_fe_parms*)

all the other arguments/parameters types match exactly, this is the
only difference.

So why isn't &checkFrontend a thing of type check_frontend_t*?

-- 
Russel.
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Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder at ekiga.net
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