I have been checking C++/CLI lately by using VC++ 2005 Express Beta 1
(should be called Alpha though).

In managed extensions we could pass managed pointers to functions taking
 unmanaged pointers as parameters by using __pin pointers:

__gc class whatever
{
 // ...
};

template<class T>
void somefun(T *p)
{
 // ...
};

int main()
{
  whatever *p=__gc new whatever;

  whatever __pin *pp=p;

  somefun(pp);

// ...
}

How can this handle to pointer conversion take place in C++/CLI? The
following does not seem to work:

ref class managed
{
};

int main()
{
 using namespace stdcli::language;

 managed ^h=gcnew managed;

 pin_ptr<managed>p=h;
}

C:\c>cl /clr temp.cpp
Microsoft (R) C/C++ Optimizing Compiler Version 14.00.40607.16
for Microsoft (R) .NET Framework version 2.00.40607.16
Copyright (C) Microsoft Corporation.  All rights reserved.

temp.cpp
temp.cpp(12) : error C3833: 'managed' : invalid target type for pin_ptr
        Cannot declare pin_ptr to a handle type. Consider declaring
pin_ptr to one of the members of 'managed'

C:\c>

Best regards,

Ioannis Vranos