diff --git a/CMakeLists.txt b/CMakeLists.txt
index a1ee6fd5f..39187b012 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -103,11 +103,11 @@ message("SDL2 Include Dir is ${SDL2_INCLUDE_DIR} ${SDL2_INCLUDE_DIRS}")
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
   message("Building for Linux")
-  add_compile_definitions(__LINUX__ _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-linux.hog\")
+  add_compile_definitions(POSIX __LINUX__ _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-linux.hog\")
   set(PLATFORM_INCLUDES "lib/linux" ${SDL2_INCLUDE_DIR} ${SDL2_INCLUDE_DIRS})
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   message("Building for MAC OSX")
-  add_compile_definitions(__LINUX__ MACOSX=1 _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-osx.hog\")
+  add_compile_definitions(POSIX MACOSX=1 _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-osx.hog\")
   set(PLATFORM_INCLUDES "lib/linux" ${SDL2_INCLUDE_DIR} ${SDL2_INCLUDE_DIRS})
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
   # Windows.h defines to avoid as many issues as possible.
diff --git a/Descent3/BriefingParse.h b/Descent3/BriefingParse.h
index e90bd6ebc..df74a2d21 100644
--- a/Descent3/BriefingParse.h
+++ b/Descent3/BriefingParse.h
@@ -50,7 +50,7 @@
 #ifndef __BRIEFPARSE_H_
 #define __BRIEFPARSE_H_
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h" //for stricmp
 #endif
 
diff --git a/Descent3/ConfigItem.h b/Descent3/ConfigItem.h
index 5bc398a25..e6e8a1009 100644
--- a/Descent3/ConfigItem.h
+++ b/Descent3/ConfigItem.h
@@ -58,7 +58,7 @@
 
 #include "newui.h"
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 void CIListBoxCallback(int ID, void *);
 void CISliderCallback(int ID, void *);
 #endif
diff --git a/Descent3/Game2DLL.cpp b/Descent3/Game2DLL.cpp
index f84a50348..bcd731145 100644
--- a/Descent3/Game2DLL.cpp
+++ b/Descent3/Game2DLL.cpp
@@ -92,7 +92,7 @@ struct game_api {
   tOSIRISModuleInit *osiris_functions;
 };
 // The exported DLL function call prototypes
-#if defined(__LINUX__)
+#if defined(POSIX)
 typedef void DLLFUNCCALL (*DLLGameCall_fp)(int eventnum, dllinfo *data);
 typedef void DLLFUNCCALL (*DLLGameInit_fp)(int *api_func, uint8_t *all_ok, int num_teams_to_use);
 typedef void DLLFUNCCALL (*DLLGameClose_fp)();
diff --git a/Descent3/LoadLevel.cpp b/Descent3/LoadLevel.cpp
index 46ae6a50a..07a0425f2 100644
--- a/Descent3/LoadLevel.cpp
+++ b/Descent3/LoadLevel.cpp
@@ -3240,7 +3240,7 @@ void ReadTerrainSkyAndLightChunk(CFILE *fp, int version) {
 
   Terrain_sky.flags = cf_ReadInt(fp);
 
-#ifdef __LINUX__
+#if defined(POSIX)
   if (FindArg("-noterrainfog") > 0) {
     Terrain_sky.flags &= ~TF_FOG;
   }
diff --git a/Descent3/Mission.cpp b/Descent3/Mission.cpp
index a21f1bffc..35f230b2c 100644
--- a/Descent3/Mission.cpp
+++ b/Descent3/Mission.cpp
@@ -1694,12 +1694,12 @@ void InitLevelScript() {
     ddio_SplitPath(Current_level->filename, NULL, filename, ext);
 #if defined(WIN32)
     strcat(filename, ".dll");
-#else
-#if defined(MACOSX)
+#elif defined(MACOSX)
     strcat(filename, ".dylib");
-#else
+#elif defined(__LINUX__)
     strcat(filename, ".so");
-#endif
+#else
+    #error Unsupported platform!
 #endif
     Osiris_LoadLevelModule(filename);
   }
diff --git a/Descent3/OsirisLoadandBind.cpp b/Descent3/OsirisLoadandBind.cpp
index d2df2c7ac..de2558dbd 100644
--- a/Descent3/OsirisLoadandBind.cpp
+++ b/Descent3/OsirisLoadandBind.cpp
@@ -438,7 +438,7 @@ bool Show_osiris_debug = false;
        // 0, only when the level ends
 
 // The exported DLL function call prototypes
-#if defined(__LINUX__)
+#if defined(POSIX)
 typedef char DLLFUNCCALL (*InitializeDLL_fp)(tOSIRISModuleInit *function_list);
 typedef void DLLFUNCCALL (*ShutdownDLL_fp)(void);
 typedef int DLLFUNCCALL (*GetGOScriptID_fp)(const char *name, uint8_t isdoor);
@@ -3144,14 +3144,14 @@ int Osiris_ExtractScriptsFromHog(int library_handle, bool is_mission_hog) {
   int count = 0;
 
   const char *script_extension;
-#if defined(__LINUX__)
 #if defined(MACOSX)
   script_extension = "*.dylib";
-#else
+#elif defined(__LINUX__)
   script_extension = "*.so";
-#endif
-#else
+#elif defined(WIN32)
   script_extension = "*.dll";
+#else
+  #error Unsupported platform!
 #endif
 
   int index;
@@ -4037,4 +4037,3 @@ void Osiris_CreateModuleInitStruct(tOSIRISModuleInit *mi) {
     mi->fp[i] = NULL;
   }
 }
-
diff --git a/Descent3/config.cpp b/Descent3/config.cpp
index a4ca9b4dd..e85d9615d 100644
--- a/Descent3/config.cpp
+++ b/Descent3/config.cpp
@@ -679,7 +679,7 @@ struct video_menu {
     sheet->AddLongRadioButton("1600x1200");
     *resolution = iTemp;
 
-#if !defined(__LINUX__)
+#if !defined(POSIX)
     // renderer bit depth
     switch (Render_preferred_bitdepth) {
     case 16:
@@ -708,7 +708,7 @@ struct video_menu {
 
     sheet->NewGroup(TXT_MONITOR, 0, 180);
     vsync = sheet->AddLongCheckBox(TXT_CFG_VSYNCENABLED, (Render_preferred_state.vsync_on != 0));
-#ifndef __LINUX__
+#if !defined(POSIX)
     sheet->AddText("");
     sheet->AddLongButton(TXT_AUTO_GAMMA, IDV_AUTOGAMMA);
 #endif
@@ -723,7 +723,7 @@ struct video_menu {
       Render_preferred_state.mipping = (*mipmapping) ? 1 : 0;
     if (vsync)
       Render_preferred_state.vsync_on = (*vsync) ? 1 : 0;
-#if !defined(__LINUX__)
+#if !defined(POSIX)
     if (bitdepth)
       Render_preferred_bitdepth = (*bitdepth) == 1 ? 32 : 16;
 #endif
@@ -753,7 +753,7 @@ struct video_menu {
 
   // process
   void process(int res) {
-#ifndef __LINUX__
+#if !defined(POSIX)
     switch (res) {
     case IDV_AUTOGAMMA:
       config_gamma();
diff --git a/Descent3/credits.cpp b/Descent3/credits.cpp
index 0277dc097..78936555a 100644
--- a/Descent3/credits.cpp
+++ b/Descent3/credits.cpp
@@ -94,7 +94,7 @@
 #include <math.h>
 #include "psrand.h"
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/Descent3/dedicated_server.cpp b/Descent3/dedicated_server.cpp
index 904888384..664cfaa2b 100644
--- a/Descent3/dedicated_server.cpp
+++ b/Descent3/dedicated_server.cpp
@@ -108,7 +108,7 @@
 #include <string.h>
 #include <stdlib.h>
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 typedef int socklen_t;
 #endif
 
@@ -788,7 +788,7 @@ void PrintDedicatedMessage(const char *fmt, ...) {
   DedicatedSocketputs(buf);
 }
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <sys/socket.h>
diff --git a/Descent3/gamesave.cpp b/Descent3/gamesave.cpp
index 7d7f6b401..c88867158 100644
--- a/Descent3/gamesave.cpp
+++ b/Descent3/gamesave.cpp
@@ -511,7 +511,7 @@ struct tLoadGameDialogData {
   chunked_bitmap chunk;
 };
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 void LoadGameDialogCB(newuiTiledWindow *wnd, void *data)
 #else
 void __cdecl LoadGameDialogCB(newuiTiledWindow *wnd, void *data)
diff --git a/Descent3/matcen.cpp b/Descent3/matcen.cpp
index 85f896f05..abbb5ce34 100644
--- a/Descent3/matcen.cpp
+++ b/Descent3/matcen.cpp
@@ -1904,7 +1904,7 @@ void InitMatcens() {
   atexit(DestroyAllMatcens);
 }
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 void DestroyAllMatcens()
 #else
 void __cdecl DestroyAllMatcens()
diff --git a/Descent3/mission_download.cpp b/Descent3/mission_download.cpp
index cbedc2fd4..dacfcc4d7 100644
--- a/Descent3/mission_download.cpp
+++ b/Descent3/mission_download.cpp
@@ -826,7 +826,7 @@ int msn_ExtractZipFile(char *zipfilename, char *mn3name) {
   return 1;
 }
 
-#ifdef __LINUX__
+#if defined(POSIX)
 char *_strlwr(char *string) {
   char *ptr = string;
   while (*ptr) {
diff --git a/Descent3/mmItem.h b/Descent3/mmItem.h
index 703546db6..9909fb832 100644
--- a/Descent3/mmItem.h
+++ b/Descent3/mmItem.h
@@ -103,7 +103,7 @@ enum tmmItemFX {
 void MenuScene(); // display menu scene
 /////////////////////////////////////////////////////////////////////
 // gcc doesn't like the tQueue template in psclass.h
-#ifdef __LINUX__
+#if defined(POSIX)
 //	tQueue
 //		a circular queue implementation
 class tmmItemQueue {
@@ -144,7 +144,7 @@ class mmItem : public UIGadget {
   int16_t m_alpha; // alpha for text item
   int16_t m_satcount;
   tmmItemFX m_curfx; // current effect
-#ifndef __LINUX__
+#if !defined(POSIX)
   tQueue<tmmItemFX, 8> m_fxqueue; // special effects queue
 #else
   tmmItemQueue m_fxqueue;
diff --git a/Descent3/multi.h b/Descent3/multi.h
index 0297013f6..d702d2206 100644
--- a/Descent3/multi.h
+++ b/Descent3/multi.h
@@ -498,7 +498,7 @@
 #include "object_external.h"
 #include "player_external.h"
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/Descent3/multi_dll_mgr.cpp b/Descent3/multi_dll_mgr.cpp
index c03f2e95b..89f99ee66 100644
--- a/Descent3/multi_dll_mgr.cpp
+++ b/Descent3/multi_dll_mgr.cpp
@@ -328,7 +328,7 @@ extern bool Multi_Gamelist_changed;
 int CheckMissionForScript(char *mission, char *script, int dedicated_server_num_teams);
 void ShowNetgameInfo(network_game *game);
 // The exported DLL function call prototypes
-#if defined(__LINUX__)
+#if defined(POSIX)
 typedef void DLLFUNCCALL (*DLLMultiCall_fp)(int eventnum);
 typedef void DLLFUNCCALL (*DLLMultiScoreCall_fp)(int eventnum, void *data);
 typedef void DLLFUNCCALL (*DLLMultiInit_fp)(int *api_fp);
diff --git a/Descent3/multi_external.h b/Descent3/multi_external.h
index 728f5a52c..7b93e631e 100644
--- a/Descent3/multi_external.h
+++ b/Descent3/multi_external.h
@@ -107,7 +107,7 @@
 #ifndef __MULTI_EXTERNAL_H_
 #define __MULTI_EXTERNAL_H_
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include <cstring>
 #include <cstdint>
 typedef uintptr_t DWORD;
diff --git a/Descent3/newui.h b/Descent3/newui.h
index bff83a635..7463fe79c 100644
--- a/Descent3/newui.h
+++ b/Descent3/newui.h
@@ -187,7 +187,7 @@
 #ifndef NEWUI_H
 #define NEWUI_H
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h" //fix some of the stricmp's
 #endif
 
diff --git a/Descent3/sdlmain.cpp b/Descent3/sdlmain.cpp
index 40f0ad7c4..ae59d345e 100644
--- a/Descent3/sdlmain.cpp
+++ b/Descent3/sdlmain.cpp
@@ -142,13 +142,13 @@ void just_exit(void) {
 #endif
 
   SDL_Quit();
-#ifdef __LINUX__
+#if defined(POSIX)
   sync(); // just in case.
 #endif
   _exit(0);
 }
 
-#ifdef __LINUX__
+#if defined(POSIX)
 void fatal_signal_handler(int signum) {
   switch (signum) {
   case SIGHUP:
@@ -612,7 +612,7 @@ int main(int argc, char *argv[]) {
     }
 
     bool run_d3 = true;
-#ifdef __LINUX__
+#if defined(POSIX)
     if (flags & APPFLAG_USESERVICE) {
       run_d3 = false;
       pid_t np = fork();
diff --git a/Descent3/terrainrender.cpp b/Descent3/terrainrender.cpp
index c0118083f..12c1f1a87 100644
--- a/Descent3/terrainrender.cpp
+++ b/Descent3/terrainrender.cpp
@@ -2717,7 +2717,7 @@ static g3Point *slist[256];
 // Draws the 2 triangles of the Terrainlist[index] (software)
 int DrawTerrainTrianglesSoftware(int index, int bm_handle, int upper_left, int lower_right) {
   /*
-  #ifndef __LINUX__
+  #if !defined(POSIX)
           int i,tlist[4],close=0,lit=0;
           float closest_z=9999;
           int color;
diff --git a/bitmap/lightmap.cpp b/bitmap/lightmap.cpp
index ddf164124..699fd1155 100644
--- a/bitmap/lightmap.cpp
+++ b/bitmap/lightmap.cpp
@@ -24,7 +24,7 @@
 #include "bitmap.h"
 #include "mono.h"
 #include "mem.h"
-#ifndef __LINUX__
+#if !defined(POSIX)
 #include "Macros.h"
 #endif
 
diff --git a/cfile/cfile.cpp b/cfile/cfile.cpp
index cabb54895..7f442f1c6 100644
--- a/cfile/cfile.cpp
+++ b/cfile/cfile.cpp
@@ -28,7 +28,7 @@
 #include <memory>
 #include <vector>
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 // Non-Linux Build Includes
 #include <io.h>
 #else
@@ -425,7 +425,7 @@ CFILE *open_file_in_directory(const std::filesystem::path &filename, const char
   fp = fopen(using_filename.u8string().c_str(), tmode);
 
   if (!fp) {
-#ifdef __LINUX__
+#if defined(POSIX)
     // If we tried to open file for reading, assume there maybe case-sensitive files
     if (tmode[0] == 'r') {
       // Try different cases of the filename
diff --git a/ddebug/debug.h b/ddebug/debug.h
index 916f7ef33..03622d4c6 100644
--- a/ddebug/debug.h
+++ b/ddebug/debug.h
@@ -133,7 +133,7 @@
 #define IDNO 7
 #endif
 // #define DEBUG_LEVEL 0		//DAJ
-#if defined(WIN32) || defined(__LINUX__)
+#if defined(WIN32) || defined(POSIX)
 constexpr const int OSMBOX_OK = 1;
 constexpr const int OSMBOX_YESNO = 2;
 constexpr const int OSMBOX_YESNOCANCEL = 3;
@@ -172,7 +172,7 @@ void Debug_ConsolePrintfAt(int n, int row, int col, const char *format, ...);
 #if !defined(RELEASE)
 #include "debugbreak.h"
 #if defined(WIN32)
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 void ddio_InternalKeyClose();
 #else
 #define debug_break()
diff --git a/legacy/briefinglocalizer/briefinglocalizerDlg.cpp b/legacy/briefinglocalizer/briefinglocalizerDlg.cpp
index 119bc1dd2..2447c9c36 100644
--- a/legacy/briefinglocalizer/briefinglocalizerDlg.cpp
+++ b/legacy/briefinglocalizer/briefinglocalizerDlg.cpp
@@ -23,7 +23,7 @@
 #include "briefinglocalizer.h"
 #include "briefinglocalizerDlg.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/legacy/inetfile/CFtp.cpp b/legacy/inetfile/CFtp.cpp
index 29815664c..99a1de6db 100644
--- a/legacy/inetfile/CFtp.cpp
+++ b/legacy/inetfile/CFtp.cpp
@@ -63,7 +63,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 // sorry, I'm lazy, I guess we could copy the defines
 // that we need to transalte winsock->linux into this header...but no need to now
 #include "inetgetfile.h"
@@ -75,14 +75,14 @@
 
 #include "CFtp.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 void *FTPObjThread(void *obj)
 #else
 void FTPObjThread(void *obj)
 #endif
 {
   ((CFtpGet *)obj)->WorkerThread();
-#ifdef __LINUX__
+#if defined(POSIX)
   return NULL;
 #endif
 }
@@ -199,7 +199,7 @@ CFtpGet::CFtpGet(char *URL, char *localfile, char *Username, char *Password) {
     m_State = FTP_STATE_INTERNAL_ERROR;
     return;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   pthread_t thread;
   if (!inet_LoadThreadLib()) {
     m_State = FTP_STATE_INTERNAL_ERROR;
@@ -216,7 +216,7 @@ CFtpGet::CFtpGet(char *URL, char *localfile, char *Username, char *Password) {
 CFtpGet::~CFtpGet() {
   if (m_ListenSock != INVALID_SOCKET) {
     shutdown(m_ListenSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_ListenSock);
 #else
     close(m_ListenSock);
@@ -224,7 +224,7 @@ CFtpGet::~CFtpGet() {
   }
   if (m_DataSock != INVALID_SOCKET) {
     shutdown(m_DataSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_DataSock);
 #else
     close(m_DataSock);
@@ -232,7 +232,7 @@ CFtpGet::~CFtpGet() {
   }
   if (m_ControlSock != INVALID_SOCKET) {
     shutdown(m_ControlSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_ControlSock);
 #else
     close(m_ControlSock);
@@ -317,7 +317,7 @@ uint32_t CFtpGet::GetFile() {
 
   m_DataSock = accept(m_ListenSock, NULL, NULL); //(SOCKADDR *)&sockaddr,&iAddrLength);
                                                  // Close the listen socket
-#ifndef __LINUX__
+#if !defined(POSIX)
   closesocket(m_ListenSock);
 #else
   close(m_ListenSock);
@@ -388,7 +388,7 @@ uint32_t CFtpGet::IssuePort() {
   // Tell the server which port to use for data.
   nReplyCode = SendFTPCommand(szCommandString);
   if (nReplyCode != 200) {
-#ifdef __LINUX__
+#if defined(POSIX)
     // I don't know if this is just Linux or do to a bug I fixed while porting to linux
     // for some reason I kept getting reply 250 here and have to read again to get the
     // "200 PORT Command OK" or whatever
@@ -485,7 +485,7 @@ uint32_t CFtpGet::ReadFTPServerReply() {
 
     if (iBytesRead == SOCKET_ERROR) {
       int iWinsockErr = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
       if (0 == iWinsockErr) {
         continue;
       }
@@ -531,7 +531,7 @@ uint32_t CFtpGet::ReadDataChannel() {
       return 0;
     nBytesRecv = recv(m_DataSock, (char *)&sDataBuffer, sizeof(sDataBuffer), 0);
 
-#ifdef __LINUX__
+#if defined(POSIX)
     if (nBytesRecv == -1) {
       int iWinsockErr = WSAGetLastError();
       if (iWinsockErr == 0) {
diff --git a/legacy/inetfile/Chttpget.cpp b/legacy/inetfile/Chttpget.cpp
index 6b79fd620..5663ecc91 100644
--- a/legacy/inetfile/Chttpget.cpp
+++ b/legacy/inetfile/Chttpget.cpp
@@ -129,7 +129,7 @@
 #define mem_free(a) free(a)
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
 
 inline void Sleep(int millis) {
   struct timeval tv;
@@ -143,7 +143,7 @@ inline void Sleep(int millis) {
 #define NW_AGHBN_LOOKUP 2
 #define NW_AGHBN_READ 3
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 void __cdecl http_gethostbynameworker(void *parm);
 #else
 void *http_gethostbynameworker(void *parm);
@@ -151,7 +151,7 @@ void *http_gethostbynameworker(void *parm);
 
 int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname);
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 void HTTPObjThread(void *obj)
 #else
 void *HTTPObjThread(void *obj)
@@ -161,7 +161,7 @@ void *HTTPObjThread(void *obj)
   ((ChttpGet *)obj)->m_Aborted = true;
   // OutputDebugString("http transfer exiting....\n");
 
-#ifdef __LINUX__
+#if defined(POSIX)
   return NULL;
 #endif
 }
@@ -264,7 +264,7 @@ void ChttpGet::GetFile(char *URL, char *localfile) {
     m_State = HTTP_STATE_INTERNAL_ERROR;
     return;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   pthread_t thread;
   if (!inet_LoadThreadLib()) {
     m_State = HTTP_STATE_INTERNAL_ERROR;
@@ -280,7 +280,7 @@ void ChttpGet::GetFile(char *URL, char *localfile) {
 ChttpGet::~ChttpGet() {
   if (m_DataSock != INVALID_SOCKET) {
     shutdown(m_DataSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_DataSock);
 #else
     close(m_DataSock);
@@ -484,7 +484,7 @@ int ChttpGet::ConnectSocket() {
   int serr = connect(m_DataSock, (SOCKADDR *)&hostaddr, sizeof(SOCKADDR));
   int cerr = WSAGetLastError();
   if (serr) {
-#ifdef __LINUX__
+#if defined(POSIX)
     while ((cerr == WSAEALREADY) || (cerr == WSAEINVAL) || (cerr == WSAEWOULDBLOCK) || (cerr == EINPROGRESS))
 #else
     while ((cerr == WSAEALREADY) || (cerr == WSAEINVAL) || (cerr == WSAEWOULDBLOCK))
@@ -529,7 +529,7 @@ char *ChttpGet::GetHTTPLine() {
 
       if (SOCKET_ERROR == iBytesRead) {
         int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
         if (WSAEWOULDBLOCK == error || 0 == error)
 #else
         if (WSAEWOULDBLOCK == error)
@@ -552,7 +552,7 @@ char *ChttpGet::GetHTTPLine() {
 
         if (SOCKET_ERROR == iBytesRead) {
           int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
           if (WSAEWOULDBLOCK == error || 0 == error)
 #else
           if (WSAEWOULDBLOCK == error)
@@ -612,7 +612,7 @@ uint32_t ChttpGet::ReadDataChannel() {
 
     if (SOCKET_ERROR == nBytesRecv) {
       int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
       if (WSAEWOULDBLOCK == error || 0 == error)
 #else
       if (WSAEWOULDBLOCK == error)
@@ -648,7 +648,7 @@ uint32_t ChttpGet::ReadDataChannel() {
 async_dns_lookup httpaslu;
 async_dns_lookup *http_lastaslu = NULL;
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 void __cdecl http_gethostbynameworker(void *parm);
 #else
 void *http_gethostbynameworker(void *parm);
@@ -672,7 +672,7 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 
 #ifdef WIN32
     _beginthread(http_gethostbynameworker, 0, newaslu);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
     pthread_t thread;
     if (!inet_LoadThreadLib()) {
       return 0;
@@ -704,20 +704,20 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 }
 
 // This is the worker thread which does the lookup.
-#ifndef __LINUX__
+#if !defined(POSIX)
 void __cdecl http_gethostbynameworker(void *parm)
 #else
 void *http_gethostbynameworker(void *parm)
 #endif
 {
-#ifdef __LINUX__
+#if defined(POSIX)
   df_pthread_detach(df_pthread_self());
 #endif
   async_dns_lookup *lookup = (async_dns_lookup *)parm;
   HOSTENT *he = gethostbyname(lookup->host);
   if (he == NULL) {
     lookup->error = true;
-#ifdef __LINUX__
+#if defined(POSIX)
     return NULL;
 #else
     return;
@@ -729,7 +729,7 @@ void *http_gethostbynameworker(void *parm)
   }
   mem_free(lookup);
 
-#ifdef __LINUX__
+#if defined(POSIX)
   return NULL;
 #endif
 }
diff --git a/legacy/inetfile/inetgetfile.cpp b/legacy/inetfile/inetgetfile.cpp
index cb6df14cf..375f1131f 100644
--- a/legacy/inetfile/inetgetfile.cpp
+++ b/legacy/inetfile/inetgetfile.cpp
@@ -90,7 +90,7 @@
 extern char *Proxy_server;
 extern int16_t Proxy_port;
 
-#ifdef __LINUX__
+#if defined(POSIX)
 pthread_create_fp df_pthread_create = NULL;
 pthread_exit_fp df_pthread_exit = NULL;
 pthread_detach_fp df_pthread_detach = NULL;
diff --git a/legacy/renderer/opengl.cpp b/legacy/renderer/opengl.cpp
index ae357f1ae..d8b0990a8 100644
--- a/legacy/renderer/opengl.cpp
+++ b/legacy/renderer/opengl.cpp
@@ -19,7 +19,7 @@
 #if defined(WIN32)
 #include <windows.h>
 #include "ddraw.h"
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 #include "linux_fix.h"
 #include "lnxscreenmode.h"
 #else
@@ -83,7 +83,7 @@ static HWND hOpenGLWnd = NULL;
 static HDC hOpenGLDC = NULL;
 HGLRC ResourceContext;
 static WORD Saved_gamma_values[256 * 3];
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 static Display *OpenGL_Display = NULL;
 static Window OpenGL_Window;
 static XVisualInfo OpenGL_VisualInfo;
@@ -355,7 +355,7 @@ void opengl_SetDefaults() {
   Last_texel_unit_set = -1;
   OpenGL_multitexture_state = false;
 
-#ifdef __LINUX__
+#if defined(POSIX)
   OpenGL_UseLists = (FindArg("-gllists")) ? true : false;
   if (OpenGL_UseLists) {
 #endif
@@ -366,7 +366,7 @@ void opengl_SetDefaults() {
     dglVertexPointer(3, GL_FLOAT, 0, GL_verts);
     dglColorPointer(4, GL_FLOAT, 0, GL_colors);
     dglTexCoordPointer(4, GL_FLOAT, 0, GL_tex_coords);
-#ifdef __LINUX__
+#if defined(POSIX)
   }
 #endif
 
@@ -494,7 +494,7 @@ int opengl_Setup(HDC glhdc) {
 
   return 1;
 }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 bool opengl_GetXConfig(Display *dpy, XVisualInfo *vis, int attrib, int *value) {
   int res;
 
@@ -783,7 +783,7 @@ int opengl_Init(oeApplication *app, renderer_preferred_state *pref_state) {
   // Save gamma values for later
   GetDeviceGammaRamp(hOpenGLDC, (LPVOID)Saved_gamma_values);
 
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   /***********************************************************
    *               LINUX OPENGL
    ***********************************************************
@@ -985,7 +985,7 @@ void opengl_Close(const bool just_resizing) {
   // Change our display back
   if (!WindowGL)
     ChangeDisplaySettings(NULL, 0);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   // Restore our video mode
   LinuxVideoMode.Lock(false);
   LinuxVideoMode.RestoreVideoMode();
@@ -1034,7 +1034,7 @@ void opengl_Close(const bool just_resizing) {
   SetDeviceGammaRamp(hOpenGLDC, (LPVOID)Saved_gamma_values);
   //	I'm freeing the DC here - samir
   ReleaseDC(hOpenGLWnd, hOpenGLDC);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 
 #else
 
@@ -1561,11 +1561,11 @@ void opengl_DrawMultitexturePolygon(int handle, g3Point **p, int nv, int map_typ
   opengl_SetMultitextureBlendMode(true);
 
   // And draw!
-#ifdef __LINUX__
+#if defined(POSIX)
   if (OpenGL_UseLists) {
 #endif
     dglDrawArrays(GL_POLYGON, 0, nv);
-#ifdef __LINUX__
+#if defined(POSIX)
   } else {
     dglBegin(GL_POLYGON);
     for (i = 0; i < nv; i++) {
@@ -1746,7 +1746,7 @@ void opengl_DrawPolygon(int handle, g3Point **p, int nv, int map_type) {
       colorp->a = alpha;
     }
 
-#ifdef __LINUX__
+#if defined(POSIX)
     // MY TEST HACK...MAYBE BAD DRIVERS? OR MAYBE THIS IS
     // HOW IT SHOULD BE DONE (STILL BUGGY)
     // Texture this polygon!
@@ -1778,11 +1778,11 @@ void opengl_DrawPolygon(int handle, g3Point **p, int nv, int map_type) {
   }
 
   // And draw!
-#ifdef __LINUX__
+#if defined(POSIX)
   if (OpenGL_UseLists) {
 #endif
     dglDrawArrays(GL_POLYGON, 0, nv);
-#ifdef __LINUX__
+#if defined(POSIX)
   } else {
     dglBegin(GL_POLYGON);
     for (i = 0; i < nv; i++) {
@@ -1880,7 +1880,7 @@ void opengl_Flip() {
 
 #if defined(WIN32)
   SwapBuffers((HDC)hOpenGLDC);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   glXWaitGL();
   glXSwapBuffers(OpenGL_Display, OpenGL_Window);
 #endif
@@ -2561,7 +2561,7 @@ void opengl_GetStatistics(tRendererStats *stats) {
   stats->texture_uploads = OpenGL_last_uploaded;
 }
 
-#ifdef __LINUX__
+#if defined(POSIX)
 void CreateFullScreenWindow(Display *dpy, Window rootwin, Window window, int DisplayScreen, int DisplayWidth,
                             int DisplayHeight) {
   // see if a motif based window manager is running.  do this by
diff --git a/legacy/renderer/renderer.cpp b/legacy/renderer/renderer.cpp
index 15435e042..8c5ddf2fd 100644
--- a/legacy/renderer/renderer.cpp
+++ b/legacy/renderer/renderer.cpp
@@ -439,7 +439,7 @@
 #endif
 
 // Renderers for Linux version
-#if defined(__LINUX__)
+#if defined(POSIX)
 #define USE_OPENGL
 #define USE_GLIDE
 // #define USE_D3D
diff --git a/lib/CZip.h b/lib/CZip.h
index 477bf2bba..38e9d7876 100644
--- a/lib/CZip.h
+++ b/lib/CZip.h
@@ -21,7 +21,7 @@
 
 #include <cstdio>
 #include <cstdint>
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/lib/bitmap.h b/lib/bitmap.h
index 5a148f740..d2b71dc97 100644
--- a/lib/bitmap.h
+++ b/lib/bitmap.h
@@ -23,7 +23,7 @@
 
 #include "cfile.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h" //needed for stricmp's throughout bitmap lib
 #endif
 
diff --git a/lib/lnxscreenmode.h b/lib/lnxscreenmode.h
index 3f036f4c9..9fac9f3c8 100644
--- a/lib/lnxscreenmode.h
+++ b/lib/lnxscreenmode.h
@@ -52,7 +52,7 @@
 #ifndef __LNXVIDEOMODE_H__
 #define __LNXVIDEOMODE_H__
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 #include <SDL.h>
diff --git a/lib/manage.h b/lib/manage.h
index 52f489b7d..abc99d8ea 100644
--- a/lib/manage.h
+++ b/lib/manage.h
@@ -26,7 +26,7 @@
 #include "bitmap.h"
 #include "manage_external.h"
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h" //for strnicmp,etc.
 #endif
 
diff --git a/lib/module.h b/lib/module.h
index 5e4c2e695..ec554d0ef 100644
--- a/lib/module.h
+++ b/lib/module.h
@@ -105,7 +105,7 @@ struct module {
   HINSTANCE handle; // handle to the DLL
 };
 //=======================================================================
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 //==========================Linux Definitions============================
 
 #define MODPROCADDRESS void *
diff --git a/lib/networking.h b/lib/networking.h
index 1b33bf1c3..a1aac7d49 100644
--- a/lib/networking.h
+++ b/lib/networking.h
@@ -189,7 +189,7 @@ static inline void INADDR_GET_SUN_SUNB(struct in_addr *st, uint8_t *s_b1, uint8_
   *s_b4 = st->S_un.S_un_b.s_b4;
 }
 
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 // Linux includes/defines
 
 #include <sys/types.h>
@@ -490,7 +490,7 @@ struct async_dns_lookup {
   bool abort;      // read only to worker thread. If this is set, don't fill in the struct.
 
   // rcg06212000 added to let us join the thread at completion...
-#ifdef __LINUX__
+#if defined(POSIX)
   SDL_Thread *threadId;
 #endif
 };
@@ -500,7 +500,7 @@ struct async_dns_lookup {
 #else
 #define CDECLCALL
 #endif
-#ifdef __LINUX__
+#if defined(POSIX)
 // rcg06192000 used to return void *.
 int CDECLCALL gethostbynameworker(void *parm);
 #else
diff --git a/lib/pstypes.h b/lib/pstypes.h
index 7458261e6..ba7efb76d 100644
--- a/lib/pstypes.h
+++ b/lib/pstypes.h
@@ -22,7 +22,7 @@
 #include <cstdlib>
 #include <cstdint>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/lib/rtperformance.h b/lib/rtperformance.h
index 595537087..e3fa83916 100644
--- a/lib/rtperformance.h
+++ b/lib/rtperformance.h
@@ -26,8 +26,8 @@
 #define USE_RTP
 #endif
 
-#if defined(__LINUX__)
-// #if defined(__LINUX__)
+#if defined(POSIX)
+// #if defined(POSIX)
 #ifdef USE_RTP
 #undef USE_RTP // no rtp for now
 #endif
@@ -35,7 +35,7 @@
 
 // use INT64 for 64bit integers
 #ifdef USE_RTP
-#if defined(__LINUX__)
+#if defined(POSIX)
 #define INT64 int64_t
 #else
 #define INT64 signed __int64
diff --git a/lib/ui.h b/lib/ui.h
index 93908cd4c..edd3bc1ea 100644
--- a/lib/ui.h
+++ b/lib/ui.h
@@ -267,7 +267,7 @@
 #ifndef UI_H
 #define UI_H
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h" //for stricmp's through code
 #endif
 
@@ -399,7 +399,7 @@ class UIGadget : public UIObject {
   void CheckFocusOnSlaves(int mx, int my);
 
 //	universal variables
-#ifdef __LINUX__ // gcc has a hard time tracing through some of the derived classes that access m_Wnd
+#if defined(POSIX) // gcc has a hard time tracing through some of the derived classes that access m_Wnd
 public:
 #else
 protected:
@@ -421,7 +421,7 @@ class UIGadget : public UIObject {
   void UnlockFocus();              // releases lock on input to gadget.
 
 //	called from outside gadget hierarchy.
-#ifdef __LINUX__ // gcc has a hard time tracing through the dervived classes of newuiButton and thinks it can't access
+#if defined(POSIX) // gcc has a hard time tracing through the dervived classes of newuiButton and thinks it can't access
                  // OnFormat()
 public:
 #else
diff --git a/linux/lnxapp.cpp b/linux/lnxapp.cpp
index f95c1a0be..34c53cd8c 100644
--- a/linux/lnxapp.cpp
+++ b/linux/lnxapp.cpp
@@ -70,7 +70,7 @@
 
 #include <cstdlib>
 #include <cctype>
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <sys/time.h>
 #include <term.h>
 #include <termios.h>
@@ -85,7 +85,7 @@
 #undef buttons
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
 static struct termios Linux_initial_terminal_settings;
 #endif
 
@@ -122,7 +122,7 @@ void LnxAppShutdown() {
   LinuxAppDontCallShutdown = true;
   if (LinuxAppFlags & OEAPP_CONSOLE) {
     con_Destroy();
-#ifdef __LINUX__
+#if defined(POSIX)
     tcsetattr(0, TCSANOW, &Linux_initial_terminal_settings);
 #endif
   }
@@ -134,7 +134,7 @@ oeLnxApplication::oeLnxApplication(unsigned flags) {
   m_AppActive = true;
 
   if (flags & OEAPP_CONSOLE) {
-#ifdef __LINUX__
+#if defined(POSIX)
     tcgetattr(0, &Linux_initial_terminal_settings);
 #endif
     con_Create(m_Flags);
@@ -150,7 +150,7 @@ oeLnxApplication::oeLnxApplication(unsigned flags) {
 
 //	Create object with a premade info
 oeLnxApplication::oeLnxApplication(tLnxAppInfo *appinfo) {
-#ifdef __LINUX__
+#if defined(POSIX)
   tcgetattr(0, &Linux_initial_terminal_settings);
 #endif
   m_Flags = appinfo->flags;
diff --git a/linux/lnxapp.h b/linux/lnxapp.h
index 486aac75d..b22a6f8e6 100644
--- a/linux/lnxapp.h
+++ b/linux/lnxapp.h
@@ -19,7 +19,7 @@
 #ifndef LNXAPP_H
 #define LNXAPP_H
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 
diff --git a/linux/lnxdata.cpp b/linux/lnxdata.cpp
index 48c09388c..aa927a5e7 100644
--- a/linux/lnxdata.cpp
+++ b/linux/lnxdata.cpp
@@ -45,7 +45,7 @@
 #include <stdio.h>
 #include <sys/types.h>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <unistd.h>
 #include <pwd.h>
 #else
@@ -215,7 +215,7 @@ bool oeLnxAppDatabase::write(const char *label, int entry) {
 
 // get the current user's name from the os
 void oeLnxAppDatabase::get_user_name(char *buffer, size_t *size) {
-#ifdef __LINUX__
+#if defined(POSIX)
   struct passwd *pwuid = getpwuid(geteuid());
 
   if ((pwuid != NULL) && (pwuid->pw_name != NULL)) {
diff --git a/manage/manage.cpp b/manage/manage.cpp
index 7d699f965..1050dbd57 100644
--- a/manage/manage.cpp
+++ b/manage/manage.cpp
@@ -441,7 +441,7 @@
 #include <cstring>
 #include <filesystem>
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 #include "descent.h"
diff --git a/mem/mem.cpp b/mem/mem.cpp
index 340548280..9c0a63410 100644
--- a/mem/mem.cpp
+++ b/mem/mem.cpp
@@ -188,7 +188,7 @@
  *
  * $NoKeywords: $
  */
-#ifndef __LINUX__
+#if !defined(POSIX)
 #include <new.h>
 #endif
 #if defined(MACOSX)
@@ -247,7 +247,7 @@ bool Mem_superlow_memory_mode = false;
 // If this is set, the mem library ignores mem_free() calls.  All the memory is then freed at once on exit.
 bool Mem_quick_exit = false;
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 // Linux memory management
 int LnxTotalMemUsed;
 
@@ -308,7 +308,7 @@ bool mem_dumpmallocstofile(char *filename) { return false; }
 
 #pragma mark -
 
-#else // defined(__LINUX__)
+#else // defined(POSIX)
 // Windows memory management
 
 // Uncomment this to detect memory leaks and memory overwrites. Slows down mallocs and frees a little.
@@ -368,7 +368,7 @@ void operator delete(void *ptr)
 int handle_program_memory_depletion(size_t size);
 HANDLE Heap;
 void mem_Init() {
-#if defined(WIN32) || defined(__LINUX__)
+#if defined(WIN32) || defined(POSIX)
   //	allocate failsafe block for memory used by any functions after we run out of memory.
   // (printf for instance needs heap memory, as well as our error library.)
   MEMORYSTATUS ms;
@@ -443,7 +443,7 @@ void mem_Init() {
   }
   return;
 #endif
-#if defined(WIN32) || defined(__LINUX__)
+#if defined(WIN32) || defined(POSIX)
   Mem_failsafe_block = mem_malloc(128);
   if (!Mem_failsafe_block) {
     Error("No available heap memory.");
diff --git a/misc/pserror.h b/misc/pserror.h
index 815974c2d..5ec401db4 100644
--- a/misc/pserror.h
+++ b/misc/pserror.h
@@ -234,7 +234,7 @@ static inline void SetDebugBreakHandlers(void (*stop)(), void (*resume)()) {
     if (_heapchk() != _HEAPOK)                                                                                         \
       Int3();                                                                                                          \
   } while (0)
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 #include "SDL.h"
 // For some reason Linux doesn't like the \ continuation character, so I have to uglify this
 #define DEBUG_BREAK()                                                                                                  \
diff --git a/misc/psglob.cpp b/misc/psglob.cpp
index d73915f51..cae5d53d3 100644
--- a/misc/psglob.cpp
+++ b/misc/psglob.cpp
@@ -39,7 +39,7 @@
 #include <stdlib.h>
 #include <ctype.h>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <ctype.h>
 #endif
 
diff --git a/module/module.cpp b/module/module.cpp
index 2deb46bdb..f6b3ecf6c 100644
--- a/module/module.cpp
+++ b/module/module.cpp
@@ -96,7 +96,7 @@
 #include "pserror.h"
 #include "ddio.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <dlfcn.h>
 
 static bool mod_FindRealFileNameCaseInsenstive(const char *directory, const char *filename, char *new_filename);
@@ -108,7 +108,7 @@ static bool mod_FindRealFileNameCaseInsenstive(const char *directory, const char
 #include <stdio.h>
 #include <stdarg.h>
 #include <string.h>
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include "linux_fix.h"
 #endif
 #if defined(WIN32) // INSTEAD OF MAKING MODULE HAVE DEPENDENCIES, PUT THE 2 DDIO FUNCTIONS I NEED HERE
@@ -158,7 +158,7 @@ static void dd_MakePath(char *newPath, const char *absolutePathHeader, const cha
   }
   va_end(args);
 }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 // Split a pathname into its component parts
 static void dd_SplitPath(const char *srcPath, char *path, char *filename, char *ext) {
   int pathStart = -1;
@@ -282,11 +282,11 @@ void mod_GetRealModuleName(const char *modfilename, char *realmodfilename) {
 #if defined(WIN32)
     strcat(filename, ".dll");
 #elif defined(__LINUX__)
-#if defined(MACOSX)
+    strcat(filename, ".so");
+#elif defined(MACOSX)
     strcat(filename, ".dylib");
 #else
-    strcat(filename, ".so");
-#endif
+    #error Unsupported platform!
 #endif
   else {
 #if defined(WIN32)
@@ -294,17 +294,18 @@ void mod_GetRealModuleName(const char *modfilename, char *realmodfilename) {
       strcat(filename, ".dll");
     else
       strcat(filename, extension);
-#elif defined(__LINUX__) && !defined(MACOSX)
+#elif defined(__LINUX__)
     if (!stricmp(extension, ".dll") || !stricmp(extension, "msl") || !stricmp(extension, "dylib"))
       strcat(filename, ".so");
     else
       strcat(filename, extension);
-#elif defined(__LINUX__) && defined(MACOSX)
+#elif defined(MACOSX)
       if (!stricmp(extension, ".dll") || !stricmp(extension, "msl") || !stricmp(extension, "so"))
         strcat(filename, ".dylib");
       else
         strcat(filename, extension);
-
+#else
+  #error Unsupported platform!
 #endif
   }
   if (*pathname != '\0')
@@ -348,7 +349,7 @@ bool mod_LoadModule(module *handle, const char *imodfilename, int flags) {
     }
     return false;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   int f = 0;
   if (flags & MODF_LAZY)
     f |= RTLD_LAZY;
@@ -398,7 +399,7 @@ bool mod_FreeModule(module *handle) {
   }
 #if defined(WIN32)
   ret = (FreeLibrary(handle->handle) != 0);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   dlclose(handle->handle); // dlclose() returns an int, but no docs say what values!!!
 #endif
   handle->handle = NULL;
@@ -460,7 +461,7 @@ MODPROCADDRESS mod_GetSymbol(module *handle, const char *symstr, uint8_t parmbyt
     }
     return NULL;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   sym = dlsym(handle->handle, symstr);
   if (!sym) {
     ModLastError = MODERR_OTHER;
@@ -476,7 +477,7 @@ int mod_GetLastError(void) {
   // Clear out the errors
 #if defined(WIN32)
   SetLastError(0);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   dlerror();
 #endif
   int ret = ModLastError;
@@ -484,7 +485,7 @@ int mod_GetLastError(void) {
   return ret;
 }
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <assert.h>
 #include <stdarg.h>
 #include <sys/stat.h>
diff --git a/movie/d3movie.cpp b/movie/d3movie.cpp
index c4bb68223..01aa91b6e 100644
--- a/movie/d3movie.cpp
+++ b/movie/d3movie.cpp
@@ -72,7 +72,7 @@ void mve_SetCallback(MovieFrameCallback_fp callBack) {
 // used to tell movie library how to render movies.
 void mve_SetRenderProperties(int16_t x, int16_t y, int16_t w, int16_t h, renderer_type type, bool hicolor) {}
 
-#ifdef __LINUX__
+#if defined(POSIX)
 // locates the case-sensitive movie file name
 std::filesystem::path mve_FindMovieFileRealName(const std::filesystem::path &movie) {
   // split into directory and file...
@@ -104,7 +104,7 @@ int mve_PlayMovie(const std::filesystem::path &pMovieName, oeApplication *pApp)
 #ifndef NO_MOVIES
   // first, find that movie..
   std::filesystem::path real_name;
-#ifdef __LINUX__
+#if defined(POSIX)
   real_name = mve_FindMovieFileRealName(pMovieName);
   if (real_name.empty()) {
     mprintf(0, "MOVIE: No such file %s\n", pMovieName.u8string().c_str());
@@ -356,7 +356,7 @@ intptr_t mve_SequenceStart(const char *mvename, void *fhandle, oeApplication *ap
 #ifndef NO_MOVIES
   // first, find that movie..
   std::filesystem::path real_name;
-#ifdef __LINUX__
+#if defined(POSIX)
   real_name = mve_FindMovieFileRealName(mvename);
   if (real_name.empty()) {
     mprintf(0, "MOVIE: No such file %s\n", mvename);
diff --git a/netcon/includes/CFtp.h b/netcon/includes/CFtp.h
index f29d6f9d6..37dfacbce 100644
--- a/netcon/includes/CFtp.h
+++ b/netcon/includes/CFtp.h
@@ -81,7 +81,7 @@
 typedef UINT_PTR SOCKET;
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
 extern int FTPObjThread(void *obj);
 #else
 extern void FTPObjThread(void *obj);
diff --git a/netcon/includes/con_dll.h b/netcon/includes/con_dll.h
index b6544ad3d..28014709d 100644
--- a/netcon/includes/con_dll.h
+++ b/netcon/includes/con_dll.h
@@ -267,7 +267,7 @@
 #include "ship.h"
 #include "pstypes.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <string.h>
 #include "linux_fix.h"
 #endif
@@ -827,7 +827,7 @@ typedef void(DLLFUNCCALL DLLAVCall_fp)(int eventnum);
 typedef void(DLLFUNCCALL DLLAVClose_fp)();
 typedef void(DLLFUNCCALL DLLAVGetVersion_fp)(int *version);
 typedef void(DLLFUNCCALL DLLRunCheck_fp)(char *d3_path);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 typedef void DLLFUNCCALL(DLLAVInit_fp)(int *ptr);
 typedef void DLLFUNCCALL(DLLAVCall_fp)(int eventnum);
 typedef void DLLFUNCCALL(DLLAVClose_fp)();
diff --git a/netcon/includes/inetgetfile.h b/netcon/includes/inetgetfile.h
index b466589fd..af4f14747 100644
--- a/netcon/includes/inetgetfile.h
+++ b/netcon/includes/inetgetfile.h
@@ -86,7 +86,7 @@
 
 // At the end of this file is an example of usage
 
-#if defined(__LINUX__)
+#if defined(POSIX)
 #include <ctype.h>
 #include <errno.h>
 #include <netinet/in.h>
@@ -100,7 +100,7 @@
 #include "linux_fix.h"
 
 // Linux includes/defines
-#if !MACOSX
+#if defined(__LINUX__)
 #include <linux/types.h>
 // #include <linux/if.h>
 #endif
diff --git a/netcon/inetfile/CFtp.cpp b/netcon/inetfile/CFtp.cpp
index 0745ae72d..5ab9471f0 100644
--- a/netcon/inetfile/CFtp.cpp
+++ b/netcon/inetfile/CFtp.cpp
@@ -74,7 +74,7 @@ typedef int socklen_t;
 #include <stdio.h>
 #include <stdlib.h>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 // sorry, I'm lazy, I guess we could copy the defines
 // that we need to transalte winsock->linux into this header...but no need to now
 #include "SDL_thread.h"
@@ -84,14 +84,14 @@ typedef int socklen_t;
 #include "CFtp.h"
 
 // MTS: only used in this file?
-#ifdef __LINUX__
+#if defined(POSIX)
 int FTPObjThread(void *obj)
 #else
 void FTPObjThread(void *obj)
 #endif
 {
   ((CFtpGet *)obj)->WorkerThread();
-#ifdef __LINUX__
+#if defined(POSIX)
   return 0;
 #endif
 }
@@ -208,7 +208,7 @@ CFtpGet::CFtpGet(char *URL, char *localfile, char *Username, char *Password) {
     m_State = FTP_STATE_INTERNAL_ERROR;
     return;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   //	pthread_t thread;
 
   SDL_Thread *thread;
@@ -231,7 +231,7 @@ CFtpGet::CFtpGet(char *URL, char *localfile, char *Username, char *Password) {
 CFtpGet::~CFtpGet() {
   if (m_ListenSock != INVALID_SOCKET) {
     shutdown(m_ListenSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_ListenSock);
 #else
     close(m_ListenSock);
@@ -239,7 +239,7 @@ CFtpGet::~CFtpGet() {
   }
   if (m_DataSock != INVALID_SOCKET) {
     shutdown(m_DataSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_DataSock);
 #else
     close(m_DataSock);
@@ -247,7 +247,7 @@ CFtpGet::~CFtpGet() {
   }
   if (m_ControlSock != INVALID_SOCKET) {
     shutdown(m_ControlSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_ControlSock);
 #else
     close(m_ControlSock);
@@ -332,7 +332,7 @@ uint32_t CFtpGet::GetFile() {
 
   m_DataSock = accept(m_ListenSock, NULL, NULL); //(SOCKADDR *)&sockaddr,&iAddrLength);
                                                  // Close the listen socket
-#ifndef __LINUX__
+#if !defined(POSIX)
   closesocket(m_ListenSock);
 #else
   close(m_ListenSock);
@@ -403,7 +403,7 @@ uint32_t CFtpGet::IssuePort() {
   // Tell the server which port to use for data.
   nReplyCode = SendFTPCommand(szCommandString);
   if (nReplyCode != 200) {
-#ifdef __LINUX__
+#if defined(POSIX)
     // I don't know if this is just Linux or do to a bug I fixed while porting to linux
     // for some reason I kept getting reply 250 here and have to read again to get the
     // "200 PORT Command OK" or whatever
@@ -500,7 +500,7 @@ uint32_t CFtpGet::ReadFTPServerReply() {
 
     if (iBytesRead == SOCKET_ERROR) {
       int iWinsockErr = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
       if (0 == iWinsockErr) {
         continue;
       }
@@ -546,7 +546,7 @@ uint32_t CFtpGet::ReadDataChannel() {
       return 0;
     nBytesRecv = recv(m_DataSock, (char *)&sDataBuffer, sizeof(sDataBuffer), 0);
 
-#ifdef __LINUX__
+#if defined(POSIX)
     if (nBytesRecv == -1) {
       int iWinsockErr = WSAGetLastError();
       if (iWinsockErr == 0) {
diff --git a/netcon/inetfile/Chttpget.cpp b/netcon/inetfile/Chttpget.cpp
index fa7f770bb..d8fb00505 100644
--- a/netcon/inetfile/Chttpget.cpp
+++ b/netcon/inetfile/Chttpget.cpp
@@ -138,7 +138,7 @@
 #define mem_free(a) free(a)
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
 
 #include "SDL_thread.h"
 
@@ -154,7 +154,7 @@ inline void Sleep(int millis) {
 #define NW_AGHBN_LOOKUP 2
 #define NW_AGHBN_READ 3
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 static void HTTPObjThread(void *obj);
 static void __cdecl http_gethostbynameworker(void *parm);
 #else
@@ -164,7 +164,7 @@ static int http_gethostbynameworker(void *parm);
 
 static int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname);
 
-#ifndef __LINUX__
+#if !defined(POSIX)
 void HTTPObjThread(void *obj)
 #else
 int HTTPObjThread(void *obj)
@@ -174,7 +174,7 @@ int HTTPObjThread(void *obj)
   ((ChttpGet *)obj)->m_Aborted = true;
   // OutputDebugString("http transfer exiting....\n");
 
-#ifdef __LINUX__
+#if defined(POSIX)
   return 0;
 #endif
 }
@@ -282,7 +282,7 @@ void ChttpGet::GetFile(char *URL, char *localfile) {
     m_State = HTTP_STATE_INTERNAL_ERROR;
     return;
   }
-#elif defined(__LINUX__)
+#elif defined(POSIX)
   //	pthread_t thread;
   SDL_Thread *thread;
 
@@ -303,7 +303,7 @@ void ChttpGet::GetFile(char *URL, char *localfile) {
 ChttpGet::~ChttpGet() {
   if (m_DataSock != INVALID_SOCKET) {
     shutdown(m_DataSock, 2);
-#ifndef __LINUX__
+#if !defined(POSIX)
     closesocket(m_DataSock);
 #else
     close(m_DataSock);
@@ -507,7 +507,7 @@ int ChttpGet::ConnectSocket() {
   int serr = connect(m_DataSock, (SOCKADDR *)&hostaddr, sizeof(SOCKADDR));
   int cerr = WSAGetLastError();
   if (serr) {
-#ifdef __LINUX__
+#if defined(POSIX)
     while ((cerr == WSAEALREADY) || (cerr == WSAEINVAL) || (cerr == WSAEWOULDBLOCK) || (cerr == EINPROGRESS))
 #else
     while ((cerr == WSAEALREADY) || (cerr == WSAEINVAL) || (cerr == WSAEWOULDBLOCK))
@@ -552,7 +552,7 @@ char *ChttpGet::GetHTTPLine() {
 
       if (SOCKET_ERROR == iBytesRead) {
         int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
         if (WSAEWOULDBLOCK == error || 0 == error)
 #else
         if (WSAEWOULDBLOCK == error)
@@ -575,7 +575,7 @@ char *ChttpGet::GetHTTPLine() {
 
         if (SOCKET_ERROR == iBytesRead) {
           int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
           if (WSAEWOULDBLOCK == error || 0 == error)
 #else
           if (WSAEWOULDBLOCK == error)
@@ -635,7 +635,7 @@ uint32_t ChttpGet::ReadDataChannel() {
 
     if (SOCKET_ERROR == nBytesRecv) {
       int error = WSAGetLastError();
-#ifdef __LINUX__
+#if defined(POSIX)
       if (WSAEWOULDBLOCK == error || 0 == error)
 #else
       if (WSAEWOULDBLOCK == error)
@@ -689,7 +689,7 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 
 #ifdef WIN32
     _beginthread(http_gethostbynameworker, 0, newaslu);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
     //		pthread_t thread;
     if (!inet_LoadThreadLib()) {
       return 0;
@@ -703,7 +703,7 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
     if (http_lastaslu)
       http_lastaslu->abort = true;
 
-#ifdef __LINUX__
+#if defined(POSIX)
     SDL_WaitThread(http_lastaslu->threadId, NULL);
 #endif
 
@@ -713,7 +713,7 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       return -1;
     if (httpaslu.done) {
       // free(http_lastaslu);
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(http_lastaslu->threadId, NULL);
 #endif
 
@@ -721,7 +721,7 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       memcpy(ip, &httpaslu.ip, sizeof(uint32_t));
       return 1;
     } else if (httpaslu.error) {
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(http_lastaslu->threadId, NULL);
 #endif
 
@@ -735,20 +735,20 @@ int http_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 }
 
 // This is the worker thread which does the lookup.
-#ifndef __LINUX__
+#if !defined(POSIX)
 void __cdecl http_gethostbynameworker(void *parm)
 #else
 int http_gethostbynameworker(void *parm)
 #endif
 {
-#ifdef __LINUX__
+#if defined(POSIX)
   // df_pthread_detach(df_pthread_self());
 #endif
   async_dns_lookup *lookup = (async_dns_lookup *)parm;
   HOSTENT *he = gethostbyname(lookup->host);
   if (he == NULL) {
     lookup->error = true;
-#ifdef __LINUX__
+#if defined(POSIX)
     return 0;
 #else
     return;
@@ -760,7 +760,7 @@ int http_gethostbynameworker(void *parm)
   }
   mem_free(lookup);
 
-#ifdef __LINUX__
+#if defined(POSIX)
   return 0;
 #endif
 }
diff --git a/netcon/inetfile/inetgetfile.cpp b/netcon/inetfile/inetgetfile.cpp
index 7a3036436..3c5401bbe 100644
--- a/netcon/inetfile/inetgetfile.cpp
+++ b/netcon/inetfile/inetgetfile.cpp
@@ -84,7 +84,7 @@
 extern char *Proxy_server;
 extern int16_t Proxy_port;
 
-#ifdef __LINUX__
+#if defined(POSIX)
 /*  ryan sez: use SDL.
 pthread_create_fp df_pthread_create = NULL;
 pthread_exit_fp df_pthread_exit = NULL;
diff --git a/netcon/mtclient/chat_api.cpp b/netcon/mtclient/chat_api.cpp
index 6f2c4888a..6026db514 100644
--- a/netcon/mtclient/chat_api.cpp
+++ b/netcon/mtclient/chat_api.cpp
@@ -23,7 +23,7 @@
 #include <cstdio>
 #include <cstring>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <sys/time.h>
 #include <unistd.h>
 #endif
@@ -202,7 +202,7 @@ int ConnectToChatServer(const char *serveraddr, int16_t chat_port, char *nicknam
 
     if (SOCKET_ERROR == connect(Chatsock, (SOCKADDR *)&Chataddr, sizeof(SOCKADDR_IN))) {
       int ret = WSAGetLastError();
-#ifndef __LINUX__
+#if !defined(POSIX)
       if (WSAEWOULDBLOCK == WSAGetLastError())
 #else
       if (EINPROGRESS == ret || 0 == ret)
@@ -456,7 +456,7 @@ const char *ChatGetString() {
     bytesread = recv(Chatsock, ch, 1, 0);
     if (bytesread == SOCKET_ERROR) {
       uint32_t lerror = WSAGetLastError();
-#ifndef __LINUX__
+#if !defined(POSIX)
       if (WSAEWOULDBLOCK != lerror)
 #else
       if (WSAEWOULDBLOCK != lerror && 0 != lerror)
diff --git a/netgames/includes/DMFC.h b/netgames/includes/DMFC.h
index 868ba7922..c3bd604cd 100644
--- a/netgames/includes/DMFC.h
+++ b/netgames/includes/DMFC.h
@@ -294,7 +294,7 @@
 #include "gamedll_header.h"
 #include "DMFCKeyCodes.h"
 
-#if ((defined __LINUX__) && (!defined __i386__))
+#if ((defined POSIX) && (!defined __i386__))
 #include <signal.h>
 #endif
 
@@ -338,7 +338,7 @@
     if (DLLDebugBreak_callback_resume)                                                                                 \
       DLLDebugBreak_callback_resume();                                                                                 \
   } while (0)
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 // For some reason Linux doesn't like the \ continuation character, so I have to uglify this
 #define DLLmprintf(...) DLLDebug_ConsolePrintf(__VA_ARGS__)
 #ifdef DEBUG_BREAK
diff --git a/networking/networking.cpp b/networking/networking.cpp
index 63cdb938b..4c1386ef2 100644
--- a/networking/networking.cpp
+++ b/networking/networking.cpp
@@ -294,8 +294,8 @@ typedef int socklen_t;
 #endif
 #include <stdlib.h>
 #include <string.h>
-#ifdef __LINUX__
-#if !MACOSX
+#if defined(POSIX)
+#if defined(__LINUX__)
 #include <netinet/in.h>
 #endif
 #include <arpa/inet.h>
@@ -519,7 +519,7 @@ struct reliable_socket {
 
 static reliable_socket reliable_sockets[MAXRELIABLESOCKETS];
 //*******************************
-#ifdef __LINUX__
+#if defined(POSIX)
 #include <fcntl.h>
 #endif
 
@@ -2069,7 +2069,7 @@ static async_dns_lookup *lastaslu = NULL;
 #define CDECLCALL
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
 int CDECLCALL gethostbynameworker(void *parm);
 #include "SDL.h"
 #include "SDL_thread.h"
@@ -2123,7 +2123,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       lastaslu->abort = true;
 
       // rcg06212000 join the thread.
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(lastaslu->threadId, NULL);
       free(lastaslu);
 #endif
@@ -2131,7 +2131,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 
     // rcg06262000 don't need all the rigamarole since we join the thread.
 
-#if (!defined(__LINUX__))
+#if (!defined(POSIX))
     async_dns_lookup *newaslu;
     newaslu = (async_dns_lookup *)mem_malloc(sizeof(async_dns_lookup));
     memset(&newaslu->ip, 0, sizeof(uint32_t));
@@ -2153,7 +2153,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 
 #ifdef WIN32
     _beginthread(gethostbynameworker, 0, newaslu);
-#elif defined(__LINUX__)
+#elif defined(POSIX)
     // rcg06192000 use SDL threads.
     /*
             nw_LoadThreadLibrary();
@@ -2196,7 +2196,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       lastaslu->abort = true;
 
       // rcg06212000 join the thread.
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(lastaslu->threadId, NULL);
 #endif
     } // if
@@ -2206,7 +2206,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       return -1;
     if (aslu.done) {
       // rcg06212000 join the thread.
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(aslu.threadId, NULL);
 #endif
 
@@ -2215,7 +2215,7 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
       return 1;
     } else if (aslu.error) {
       // rcg06212000 join the thread.
-#ifdef __LINUX__
+#if defined(POSIX)
       SDL_WaitThread(aslu.threadId, NULL);
 #else
       mem_free(lastaslu);
@@ -2230,14 +2230,14 @@ int nw_Asyncgethostbyname(uint32_t *ip, int command, char *hostname) {
 }
 
 // This is the worker thread which does the lookup.
-#ifdef __LINUX__
+#if defined(POSIX)
 int CDECLCALL gethostbynameworker(void *parm)
 #else
 void CDECLCALL gethostbynameworker(void *parm)
 #endif
 {
   // rcg06192000 nope.
-  //	#ifdef __LINUX__
+  //	#if defined(POSIX)
   //	dpthread_detach(dpthread_self());
   //	#endif
 
@@ -2249,7 +2249,7 @@ void CDECLCALL gethostbynameworker(void *parm)
 
   if (he == NULL) {
     lookup->error = true;
-#ifdef __LINUX__
+#if defined(POSIX)
     return 0;
 #else
     return;
@@ -2267,11 +2267,11 @@ void CDECLCALL gethostbynameworker(void *parm)
   }
 
 // rcg06252000 don't free this, 'cause we need the threadId.
-#ifndef __LINUX__
+#if !defined(POSIX)
   mem_free(lookup);
 #endif
 
-#ifdef __LINUX__
+#if defined(POSIX)
   return 0;
 #endif
 }
diff --git a/renderer/HardwareOpenGL.cpp b/renderer/HardwareOpenGL.cpp
index 8e85bc894..faabca44b 100644
--- a/renderer/HardwareOpenGL.cpp
+++ b/renderer/HardwareOpenGL.cpp
@@ -446,7 +446,7 @@ int opengl_Setup(oeApplication *app, int *width, int *height) {
     OpenGLDLLHandle = LoadOpenGLDLL(gl_library);
     if (!(OpenGLDLLHandle)) {
       // rcg07072000 last ditch effort...
-#ifdef __LINUX__
+#if defined(POSIX)
       strcpy(gl_library, "libGL.so.1");
 #else
       strcpy(gl_library, "opengl32.dll");
diff --git a/renderer/dyna_gl.h b/renderer/dyna_gl.h
index 2e7aa32b3..7df688b15 100644
--- a/renderer/dyna_gl.h
+++ b/renderer/dyna_gl.h
@@ -31,7 +31,7 @@
 
 #if defined(WIN32)
 #define GLFUNCCALL __stdcall
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 #include <unistd.h>
 #define GLFUNCCALL
 #endif
@@ -488,7 +488,7 @@ module *LoadOpenGLDLL(const char *dllname) {
   dwglGetProcAddress = (wglGetProcAddress_fp)mod_GetSymbol(&OpenGLDLLInst, "wglGetProcAddress", 255);
   if (!dwglGetProcAddress)
     goto dll_error;
-#elif defined(__LINUX__)
+#elif defined(POSIX)
 
   // bk000614 - have to fix globals
   extern glAlphaFunc_fp dglAlphaFunc;
diff --git a/scripts/osiris_import.h b/scripts/osiris_import.h
index 50f2740c7..745e65839 100644
--- a/scripts/osiris_import.h
+++ b/scripts/osiris_import.h
@@ -24,7 +24,7 @@
 
 #include "osiris_common.h"
 
-#ifdef __LINUX__
+#if defined(POSIX)
 #include "linux_lib.h"
 #endif
 
diff --git a/sndlib/soundload.cpp b/sndlib/soundload.cpp
index 87ce27598..7407e07c3 100644
--- a/sndlib/soundload.cpp
+++ b/sndlib/soundload.cpp
@@ -241,7 +241,7 @@
 #include "room.h"
 #include "doorway.h"
 
-#if defined(WIN32) || defined(__LINUX__)
+#if defined(WIN32) || defined(POSIX)
 #include "../manage/soundpage.h"
 #include "../Descent3/sounds.h"
 #endif
diff --git a/ui/UIButton.cpp b/ui/UIButton.cpp
index 48692280b..4b4c9fbf0 100644
--- a/ui/UIButton.cpp
+++ b/ui/UIButton.cpp
@@ -125,7 +125,7 @@
 
 #include <string.h>
 
-#ifdef __LINUX__
+#if defined(POSIX)
 int UIButton::m_ButtonFont;
 #endif