diff --git a/include/boost/system/api_config.hpp b/include/boost/system/api_config.hpp
index 28b8bec..f294c92 100644
--- a/include/boost/system/api_config.hpp
+++ b/include/boost/system/api_config.hpp
@@ -21,22 +21,29 @@
 
 //--------------------------------------------------------------------------------------//
 
-#ifndef BOOST_SYSTEM_API_CONFIG_HPP                  
+#ifndef BOOST_SYSTEM_API_CONFIG_HPP
 #define BOOST_SYSTEM_API_CONFIG_HPP
 
-# if defined(BOOST_POSIX_API) || defined(BOOST_WINDOWS_API)
-#   error user defined BOOST_POSIX_API or BOOST_WINDOWS_API not supported
+# if defined(BOOST_SYSTEM_POSIX_API) || defined(BOOST_SYSTEM_WINDOWS_API)
+#   error user defined BOOST_SYSTEM_POSIX_API or BOOST_SYSTEM_WINDOWS_API not supported
 # endif
 
-//  BOOST_POSIX_API or BOOST_WINDOWS_API specify which API to use
+//  BOOST_SYSTEM_POSIX_API or BOOST_SYSTEM_WINDOWS_API specify which API to use
 //    Cygwin/MinGW does not predefine _WIN32.
 //    Standalone MinGW and all other known Windows compilers do predefine _WIN32
 //    Compilers that predefine _WIN32 or __MINGW32__ do so for Windows 64-bit builds too.
 
+# if (defined(_WIN32) || defined(__WIN32__) || defined(WIN32) )
+#   define BOOST_SYSTEM_WINDOWS_API
+# else
+#   define BOOST_SYSTEM_POSIX_API
+# endif
+
+//# if (defined(_WIN32) || defined(__WIN32__) || defined(WIN32) || defined(__CYGWIN__))
 # if defined(_WIN32) || defined(__CYGWIN__) // Windows default, including MinGW and Cygwin
 #   define BOOST_WINDOWS_API
 # else
-#   define BOOST_POSIX_API 
+#   define BOOST_POSIX_API
 # endif
-                                     
-#endif  // BOOST_SYSTEM_API_CONFIG_HPP 
+
+#endif  // BOOST_SYSTEM_API_CONFIG_HPP
diff --git a/include/boost/system/config.hpp b/include/boost/system/config.hpp
index bf78051..0b19da8 100644
--- a/include/boost/system/config.hpp
+++ b/include/boost/system/config.hpp
@@ -7,11 +7,23 @@
 
 //  See http://www.boost.org/libs/system for documentation.
 
-#ifndef BOOST_SYSTEM_CONFIG_HPP                  
+#ifndef BOOST_SYSTEM_CONFIG_HPP
 #define BOOST_SYSTEM_CONFIG_HPP
 
 #include <boost/config.hpp>
-#include <boost/system/api_config.hpp>  // for BOOST_POSIX_API or BOOST_WINDOWS_API
+
+#if defined(BOOST_SYSTEM_SOURCE) && !defined(BOOST_USE_WINDOWS_H)
+#define BOOST_USE_WINDOWS_H
+#endif
+
+#include <boost/system/api_config.hpp>  // for BOOST_SYSTEM_POSIX_API or BOOST_SYSTEM_WINDOWS_API
+
+#ifdef BOOST_SYSTEM_INLINED
+#define BOOST_SYSTEM_INLINE inline
+#define BOOST_SYSTEM_DECL
+
+#else
+#define BOOST_SYSTEM_INLINE
 
 // This header implements separate compilation features as described in
 // http://www.boost.org/more/separate_compilation.html
@@ -21,14 +33,14 @@
 #if defined(BOOST_ALL_DYN_LINK) || defined(BOOST_SYSTEM_DYN_LINK)
 # if defined(BOOST_SYSTEM_SOURCE)
 #   define BOOST_SYSTEM_DECL BOOST_SYMBOL_EXPORT
-# else 
+# else
 #   define BOOST_SYSTEM_DECL BOOST_SYMBOL_IMPORT
 # endif
 #else
 # define BOOST_SYSTEM_DECL
 #endif
 
-//  enable automatic library variant selection  ----------------------------------------// 
+//  enable automatic library variant selection  ----------------------------------------//
 
 #if !defined(BOOST_SYSTEM_SOURCE) && !defined(BOOST_ALL_NO_LIB) && !defined(BOOST_SYSTEM_NO_LIB)
 //
@@ -48,5 +60,7 @@
 #include <boost/config/auto_link.hpp>
 #endif  // auto-linking disabled
 
+#endif // BOOST_SYSTEM_INLINED
+
 #endif // BOOST_SYSTEM_CONFIG_HPP
 
diff --git a/include/boost/system/cygwin_error.hpp b/include/boost/system/cygwin_error.hpp
index ea3528b..a042db2 100644
--- a/include/boost/system/cygwin_error.hpp
+++ b/include/boost/system/cygwin_error.hpp
@@ -7,8 +7,8 @@
 
 //  See library home page at http://www.boost.org/libs/system
 
-#ifndef BOOST_CYGWIN_ERROR_HPP
-#define BOOST_CYGWIN_ERROR_HPP
+#ifndef BOOST_SYSTEM_CYGWIN_ERROR_HPP
+#define BOOST_SYSTEM_CYGWIN_ERROR_HPP
 
 //  This header is effectively empty for compiles on operating systems where
 //  it is not applicable.
@@ -27,7 +27,7 @@ namespace boost
 
     //  User code should use the portable "posix" enums for POSIX errors; this
     //  allows such code to be portable to non-POSIX systems. For the non-POSIX
-    //  errno values that POSIX-based systems typically provide in addition to 
+    //  errno values that POSIX-based systems typically provide in addition to
     //  POSIX values, use the system specific enums below.
 
    namespace cygwin_error
@@ -53,4 +53,4 @@ namespace boost
 
 #endif  // __CYGWIN__
 
-#endif  // BOOST_CYGWIN_ERROR_HPP
+#endif  // BOOST_SYSTEM_CYGWIN_ERROR_HPP