When using Boost Interprocess on Windows with Visual C++ Language Extensions turned off, unistd.h gets included

[derek.kivi@…]

We are using the Interprocess library to make use of shared memory within our code. We are experiencing the following problem when building on Windows.

Some of our projects are trying to include unistd.h from workaround.hpp. It looks like this happens if BOOST_WINDOWS is not defined. Tracing back through the header files I pieced together that BOOST_WINDOWS is not defined if BOOST_DISABLE_WIN32 is defined (win32.hpp). And BOOST_DISABLE_WIN32 gets defined if _MSC_EXTENSIONS is not defined (visualc.hpp).

From the MSDN documentation, _MSC_EXTENSIONS is not defined if the Visual C++ Language Extensions are turned off, and in fact they are turned off for these projects.

[Ion Gaztañaga]

Extensions are necessary to call Windows API functions and also because Boost.DateTime needs them.