diff --git a/common/port.h b/common/port.h
index 0c1baddd..102b6dff 100644
--- a/common/port.h
+++ b/common/port.h
@@ -20,14 +20,10 @@ GNU General Public License for more details.
 #include "build.h"
 
 #if !XASH_WIN32
-	#include <dlfcn.h>
-	#include <unistd.h>
 
-	#define PATH_SPLITTER "/"
 
 	#if XASH_APPLE
 		#include <sys/syslimits.h>
-		#include "TargetConditionals.h"
 		#define OS_LIB_EXT "dylib"
 		#define OPEN_COMMAND "open"
 	#else
@@ -54,20 +50,35 @@ GNU General Public License for more details.
 
 	#define _inline	static inline
 	#define FORCEINLINE inline __attribute__((always_inline))
+
+#if XASH_POSIX
+	#define PATH_SPLITTER "/"
+	#include <unistd.h>
+	#include <dlfcn.h>
 	#define O_BINARY 0 // O_BINARY is Windows extension
 	#define O_TEXT 0 // O_TEXT is Windows extension
-
-	// Windows functions to Linux equivalent
+	// Windows functions to posix equivalent
 	#define _mkdir( x )					mkdir( x, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH )
 	#define LoadLibrary( x )			dlopen( x, RTLD_NOW )
 	#define GetProcAddress( x, y )		dlsym( x, y )
 	#define SetCurrentDirectory( x )	(!chdir( x ))
 	#define FreeLibrary( x )			dlclose( x )
+	#define tell( a )					lseek(a, 0, SEEK_CUR)
+	#define HAVE_DUP
+#endif
+
+#if XASH_DOS4GW
+	#define PATH_SPLITTER "\\"
+	#define LoadLibrary( x ) (0)
+	#define GetProcAddress( x, y ) (0)
+	#define FreeLibrary( x ) (0)
+	#define SetCurrentDirectory( x )	(!chdir( x ))
+#endif
 	//#define MAKEWORD( a, b )			((short int)(((unsigned char)(a))|(((short int)((unsigned char)(b)))<<8)))
 	#define max( a, b )                 (((a) > (b)) ? (a) : (b))
 	#define min( a, b )                 (((a) < (b)) ? (a) : (b))
-	#define tell( a )					lseek(a, 0, SEEK_CUR)
 
+	/// TODO: check if we may clean this defines, it should not appear in non-platform code!
 	typedef unsigned char	BYTE;
 	typedef short int	    WORD;
 	typedef unsigned int    DWORD;
@@ -125,6 +136,8 @@ GNU General Public License for more details.
 		// windows NameForFunction not implemented yet
 		#define XASH_ALLOW_SAVERESTORE_OFFSETS
 	#endif
+	#define HAVE_DUP
+
 #endif //WIN32
 #ifndef XASH_LOW_MEMORY
 #define XASH_LOW_MEMORY 0