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From: Christopher Eltschka <celtschk@physik.tu-muenchen.de>
Subject: function pointer types(was: Re: atexit() behavior)
Date: 1998/12/01
Message-ID: <3663B9D8.283B0424@physik.tu-muenchen.de>#1/1
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Francis Glassborow wrote:

[...]

> I think they have different signatures because the parameters are:
> 
> pointer to extern "C" function
> and
> pointer to extern "C++" function
> 
> and these types are differentiable.

Does that mean that I can do

bool is_c_function(void(*)()) { return false; }
extern "C"
{
  bool is_c_function(void(*)()) { return true; }
}

and use that to differentiate between C and C++ functions?

BTW, is there (in any direction) an automatic conversion between
C and C++ function pointers?
That is, is any of the following initialisations allowed?

extern "C" { typedef void (*c_ptr)(); }
typedef void (*cpp_ptr)();

extern "C" void f();
void g();
void h() throw();

cpp_ptr p1 = &f; // allowed?
c_ptr   p2 = &g; // allowed?
c_ptr   p3 = &h; // allowed?


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