the getsockname() function call takes a SOCKET as its first parameter:
\nint getsockname(\n  SOCKET s,                    \n  struct sockaddr FAR *name,  \n  int FAR *namelen            \n);\n\n
(The above taken from the WinSock documentation)

A SOCKET is a "handle" to a socket object. How this "handle" is implemented is implementation-dependent, but on Windoze platforms, handles are defined as pointers. Indeed, the definition of a SOCKET in winsock.h is:
\ntypedef UINT_PTR        SOCKET;\n


where a UINT_PTR is a pointer to an unsigned int.

So what you're doing is implicitly casting an int to a pointer type, and the compiler is (rightly) bitching about it.

To fix it, define the parameter f as type SOCKET instead of type int, or explicitly cast f to the SOCKET type.
<rant>
(NOTE: I don't give a flying shit if these yahoos are from the mighty MIT, passing a socket handle as an int instead of as a SOCKET is really bad coding!. If this is what MIT is pumping out, then it's no wonder why the Indians are eating our lunch!)
</rant>