diff --git a/common/include/PS2Eext.h b/common/include/PS2Eext.h
index 0011a3e240..be404c231d 100644
--- a/common/include/PS2Eext.h
+++ b/common/include/PS2Eext.h
@@ -20,17 +20,24 @@
 #include <string>
 #include <cstdarg>
 
-#ifdef _MSC_VER
+#if defined(_MSC_VER)
 #include <windows.h>
 #include <windowsx.h>
 #include <commctrl.h>
 
 #define EXPORT_C_(type) extern "C" type CALLBACK
-#else
+
+#elif defined(GTK_MAJOR_VERSION)
+
 #include <gtk/gtk.h>
 #include <cstring>
 
 #define EXPORT_C_(type) extern "C" __attribute__((stdcall,externally_visible,visibility("default"))) type
+
+#else
+
+#define EXPORT_C_(type) extern "C" __attribute__((stdcall,externally_visible,visibility("default"))) type
+
 #endif
 
 //#include "PS2Edefs.h"
@@ -161,7 +168,7 @@ struct PluginConf
     }
 };
 
-#ifdef __linux__
+#if defined(GTK_MAJOR_VERSION)
 
 static void SysMessage(const char *fmt, ...)
 {
@@ -221,6 +228,48 @@ static void __forceinline PluginNullAbout(const char *aboutText)
 
 #define ENTRY_POINT /* We don't need no stinkin' entry point! */
 
+
+#elif defined(__WXMAC__) || defined(__APPLE__)
+
+static void SysMessage(const char *fmt, ...)
+{
+    va_list list;
+    char msg[512];
+
+    va_start(list, fmt);
+    vsprintf(msg, fmt, list);
+    va_end(list);
+
+    if (msg[strlen(msg)-1] == '\n') msg[strlen(msg)-1] = 0;
+
+    // TODO OSX can we use WX MessageBox here or should Cocoa MessageBox used?
+}
+
+static void SysMessage(const wchar_t *fmt, ...)
+{
+    va_list list;
+    wchar_t msg[512];
+
+    va_start(list, fmt);
+    //vsprintf(msg, fmt, list);
+    va_end(list);
+
+    // TODO OSX can we use WX MessageBox here or should Cocoa MessageBox used?
+}
+
+static void __forceinline PluginNullConfigure(std::string desc, int &log)
+{
+    SysMessage("This space intentionally left blank.");
+}
+
+static void __forceinline PluginNullAbout(const char *aboutText)
+{
+    SysMessage(aboutText);
+}
+
+#define ENTRY_POINT /* We don't need no stinkin' entry point! */ // TODO OSX WTF is this anyway?
+
+
 #else
 
 #define usleep(x)	Sleep(x / 1000)
diff --git a/common/include/Pcsx2Defs.h b/common/include/Pcsx2Defs.h
index 1402e19a97..4d69fdadbd 100644
--- a/common/include/Pcsx2Defs.h
+++ b/common/include/Pcsx2Defs.h
@@ -23,6 +23,14 @@
 #define __linux__
 #endif
 
+// make sure __POSIX__ is defined for all systems where we assume POSIX
+// compliance
+#if defined(__linux__) || defined(__APPLE__) || defined(__unix__) || defined(__CYGWIN__) || defined(__LINUX__)
+#	if !defined(__POSIX__)
+#		define __POSIX__ 1
+#	endif
+#endif
+
 #include "Pcsx2Types.h"
 
 #ifdef _MSC_VER
diff --git a/common/include/Utilities/MemcpyFast.h b/common/include/Utilities/MemcpyFast.h
index 4200e22ba6..3efa3bbf2d 100644
--- a/common/include/Utilities/MemcpyFast.h
+++ b/common/include/Utilities/MemcpyFast.h
@@ -15,7 +15,7 @@
 
 #pragma once
 
-#ifdef __linux__
+#if defined(__POSIX__)
 #	include "lnx_memzero.h"
 #else
 #	include "win_memzero.h"
diff --git a/common/include/Utilities/PageFaultSource.h b/common/include/Utilities/PageFaultSource.h
index a22b32b66e..8868c8f3df 100644
--- a/common/include/Utilities/PageFaultSource.h
+++ b/common/include/Utilities/PageFaultSource.h
@@ -271,7 +271,7 @@ protected:
 	virtual void CommitBlocks( uptr page, uint blocks );
 };
 
-#ifdef __linux__
+#ifdef __POSIX__
 
 #	define PCSX2_PAGEFAULT_PROTECT
 #	define PCSX2_PAGEFAULT_EXCEPT
diff --git a/common/include/Utilities/Threading.h b/common/include/Utilities/Threading.h
index 7751204dbd..e21522ae2e 100644
--- a/common/include/Utilities/Threading.h
+++ b/common/include/Utilities/Threading.h
@@ -19,6 +19,10 @@
 #include <errno.h> // EBUSY
 #include <pthread.h>
 
+#ifdef __APPLE__
+#include <mach/semaphore.h>
+#endif
+
 #include "Pcsx2Defs.h"
 #include "ScopedPtr.h"
 #include "TraceLog.h"
@@ -66,11 +70,7 @@ extern ConsoleLogSource_Threading pxConLog_Thread;
 //#define PCSX2_THREAD_LOCAL 0		// uncomment this line to force-disable native TLS (useful for testing TlsVariable on windows/linux)
 
 #ifndef PCSX2_THREAD_LOCAL
-#	ifdef __WXMAC__
-#		define PCSX2_THREAD_LOCAL 0
-#	else
-#		define PCSX2_THREAD_LOCAL 1
-#	endif
+#	define PCSX2_THREAD_LOCAL 1
 #endif
 
 class wxTimeSpan;
@@ -252,7 +252,12 @@ namespace Threading
 	class Semaphore
 	{
 	protected:
+#ifdef __APPLE__
+		semaphore_t m_sema;
+		int m_counter;
+#else
 		sem_t m_sema;
+#endif
 
 	public:
 		Semaphore();