diff --git a/contrib/win32/w32-posix-prototype/win32posix/UnitTests/UnitTests.vcxproj b/contrib/win32/w32-posix-prototype/win32posix/UnitTests/UnitTests.vcxproj
index 966a22d..14c2746 100644
--- a/contrib/win32/w32-posix-prototype/win32posix/UnitTests/UnitTests.vcxproj
+++ b/contrib/win32/w32-posix-prototype/win32posix/UnitTests/UnitTests.vcxproj
@@ -73,6 +73,7 @@
     <LinkIncremental>true</LinkIncremental>
     <OutDir>$(SolutionDir)bin\unittests\$(Platform)\$(Configuration)\</OutDir>
     <IntDir>$(Platform)\$(Configuration)\$(TargetName)\</IntDir>
+    <IncludePath>$(SolutionDir)\win32posix\inc;$(VC_IncludePath);$(WindowsSDK_IncludePath);</IncludePath>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <LinkIncremental>true</LinkIncremental>
@@ -90,7 +91,8 @@
       <WarningLevel>Level3</WarningLevel>
       <Optimization>Disabled</Optimization>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <AdditionalIncludeDirectories>$(SolutionDir)\win32posix</AdditionalIncludeDirectories>
+      <AdditionalIncludeDirectories>
+      </AdditionalIncludeDirectories>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
diff --git a/contrib/win32/w32-posix-prototype/win32posix/UnitTests/socket_tests.c b/contrib/win32/w32-posix-prototype/win32posix/UnitTests/socket_tests.c
index 319d317..f2faa87 100644
--- a/contrib/win32/w32-posix-prototype/win32posix/UnitTests/socket_tests.c
+++ b/contrib/win32/w32-posix-prototype/win32posix/UnitTests/socket_tests.c
@@ -1,4 +1,7 @@
-#include "w32posix.h"
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
 #include "test_helper.h"
 
 #define PORT "34912"  
@@ -7,6 +10,7 @@
 int listen_fd, accept_fd, connect_fd, ret;
 struct addrinfo hints,*servinfo;
 fd_set read_set, write_set, except_set;
+struct timeval time_val;
 
 int
 unset_nonblock(int fd)
@@ -129,11 +133,11 @@ socket_syncio_tests()
     ASSERT_INT_EQ(errno, EBADF);
     FD_ZERO(&read_set);
     FD_SET(20, &read_set);
-    ASSERT_INT_EQ(select(21, &read_set, NULL, NULL, NULL), -1);
+    ASSERT_INT_EQ(select(21, &read_set, NULL, NULL, &time_val), -1);
     ASSERT_INT_EQ(errno, EBADF);
     FD_ZERO(&write_set);
     FD_SET(21, &write_set);
-    ASSERT_INT_EQ(select(22, NULL, &write_set, NULL, NULL), -1);
+    ASSERT_INT_EQ(select(22, NULL, &write_set, NULL, &time_val), -1);
     ASSERT_INT_EQ(errno, EBADF);
     TEST_DONE();
 
diff --git a/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/sys/socket.h b/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/sys/socket.h
new file mode 100644
index 0000000..b58fcb2
--- /dev/null
+++ b/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/sys/socket.h
@@ -0,0 +1 @@
+#include "..\..\w32posix.h"
\ No newline at end of file
diff --git a/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/unistd.h b/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/unistd.h
new file mode 100644
index 0000000..149332c
--- /dev/null
+++ b/contrib/win32/w32-posix-prototype/win32posix/win32posix/inc/unistd.h
@@ -0,0 +1 @@
+#include "..\w32posix.h"
\ No newline at end of file
diff --git a/contrib/win32/w32-posix-prototype/win32posix/win32posix/w32fd.c b/contrib/win32/w32-posix-prototype/win32posix/win32posix/w32fd.c
index 7602426..c46bfe6 100644
--- a/contrib/win32/w32-posix-prototype/win32posix/win32posix/w32fd.c
+++ b/contrib/win32/w32-posix-prototype/win32posix/win32posix/w32fd.c
@@ -286,13 +286,7 @@ int w32_isatty(int fd) {
 }
 
 FILE* w32_fdopen(int fd, const char *mode) {
-    errno = 0;
-    if ((fd > MAX_FDS - 1) || fd_table.w32_ios[fd] == NULL) {
-        errno = EBADF;
-        debug("bad fd: %d", fd);
-        return NULL;
-    }
-
+    CHECK_FD(fd);
     return fileio_fdopen(fd_table.w32_ios[fd], mode);
 }
 
@@ -488,12 +482,14 @@ int w32_select(int fds, fd_set* readfds, fd_set* writefds, fd_set* exceptfds, co
 
 
 int w32_dup(int oldfd) {
+    CHECK_FD(oldfd);
     errno = EOPNOTSUPP;
     debug("ERROR: dup is not implemented yet");
     return -1;
 }
 
 int w32_dup2(int oldfd, int newfd) {
+    CHECK_FD(oldfd);
     errno = EOPNOTSUPP;
     debug("ERROR: dup2 is not implemented yet");
     return -1;
diff --git a/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj b/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj
index a513483..125a9c0 100644
--- a/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj
+++ b/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj
@@ -145,6 +145,8 @@
   <ItemGroup>
     <ClInclude Include="debug.h" />
     <ClInclude Include="defs.h" />
+    <ClInclude Include="inc\sys\socket.h" />
+    <ClInclude Include="inc\unistd.h" />
     <ClInclude Include="w32fd.h" />
     <ClInclude Include="w32posix.h" />
   </ItemGroup>
diff --git a/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj.filters b/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj.filters
index 15b911b..30d3b0e 100644
--- a/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj.filters
+++ b/contrib/win32/w32-posix-prototype/win32posix/win32posix/win32posix.vcxproj.filters
@@ -13,6 +13,12 @@
       <UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
       <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
     </Filter>
+    <Filter Include="inc">
+      <UniqueIdentifier>{bcb2ad09-217d-43e3-b3f0-0e95ef6b8023}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="inc\sys">
+      <UniqueIdentifier>{a8ebc7ed-da32-4692-82b6-6d49d420dd5b}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="socketio.c">
@@ -44,5 +50,11 @@
     <ClInclude Include="debug.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="inc\unistd.h">
+      <Filter>inc</Filter>
+    </ClInclude>
+    <ClInclude Include="inc\sys\socket.h">
+      <Filter>inc\sys</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>
\ No newline at end of file