---------- Forwarded message ---------- From: "Darren Garvey" <darren.garvey@gmail.com> To: boost-users@lists.boost.org Date: Fri, 21 Mar 2008 00:13:07 +0000 Subject: Re: [Boost-users] boost::asio Visual Studio 8 - fatal error C1189: #error : WinSock.h has already been included Hi Julian,

On 18/03/2008, Julian Cain <jolix@mac.com> wrote:

...

I have upgraded to VS 8.0 Standard and when compiling ASIO errors on the following:

1>Unknown compiler version - please run the configure tests and report the results 1>C:\tor\trunk\lib\boost\boost/asio/detail/socket_types.hpp(27) : fatal error C1189: #error : WinSock.h has already been included

Is this a known problem?

What do you mean by 'compiling asio'? It is a header-only library. :)

The problem you're seeing is because the (old) winsock.h header has been included. Most people that see this do because they've included windows.h *before* the asio headers.

You can get around this by defining WIN32_LEAN_AND_MEAN (something like that) before including windows.h, or just by including windows.h after everything else.

Regards, Darren

I've noticed the same behavior. I understand there's a workaround, but in my opinion it's still a bug. asio.hpp has a requirement that it must be #included "early enough" or else it won't compile. That's not a well-behaved header, and it's not "boost-y". Other boost components can be #included much later than <windows.h> and they will go through the whole boost/config process and re-including windows.h or winsock.h with no problems. - Alex