Sorry for the spam. I got the answer, how to do it. Ignore my previous mail.

[quote]

#include <boost/shared_ptr.hpp>
#include <iostream>
using namespace std;

class A {
    public:
    void hello () { cout << "Hello, friends...!" << endl; }
};

typedef boost::shared_ptr<A> APtr;

void* callbk (void* o) {
    APtr a = *static_cast<APtr*>(o);
    a->hello();
}

int main() {
A* rawPtr = new A;
boost::shared_ptr<A>sPtr(rawPtr);
callbk((void*)&sPtr);
return 0;
}
[/quote]

warm regars,

From: Mupparthy Ravindranath <rv_nath@yahoo.com>
To: "boost-users@lists.boost.org" <boost-users@lists.boost.org>
Sent: Tuesday, 10 May 2011 1:26 PM
Subject: How to cast a boost::shared_ptr to void*

Hi all,

My requirement is to cast an object of type shared_ptr as void*, so that I can send it to a callback function that accepts a void*. I cannot change callback the function signature because it is part of an existing legacy code.

In the existing code, I am sending a raw object pointer (instead of shared_ptr). Now, if I want to pass a shared_ptr, it won't compile because I cannot cast the shared ptr to void*.

Can anyone suggest some workaround for this. I tried searching the mailing lists and internet, but not much luck.

regards,