Updated platform specific #if's to report unimplemented code when compiling with FL_PORTING defined and WIN32 and __APPLE__ undefined>

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@10989 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

66 files changed, 396 insertions, 12 deletions

diff --git a/src/Fl.cxx b/src/Fl.cxx
index 357fb55f0..2976baa3c 100644
--- a/src/Fl.cxx
+++ b/src/Fl.cxx
@@ -59,6 +59,13 @@
 #endif // DEBUG || DEBUG_WATCH
 
 #ifdef WIN32
+#elif defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement global variables for your platform here"
+#else // X11
+#endif
+
+#ifdef WIN32
 #  include <ole2.h>
 void fl_free_fonts(void);
 HBRUSH fl_brush_action(int action);
@@ -243,6 +250,10 @@ int Fl::event_inside(const Fl_Widget *o) /*const*/ {
 
 // implementation in Fl_cocoa.mm (was Fl_mac.cxx)
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement timers in your platform specific core file"
+
 #else
 
 //
@@ -543,6 +554,10 @@ double Fl::wait(double time_to_wait) {
   run_checks();
   return fl_mac_flush_and_wait(time_to_wait);
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement waiting for a timer or a message from the system"
+
 #else
 
   if (first_timeout) {
@@ -676,7 +691,11 @@ int Fl::check() {
   \endcode
 */
 int Fl::ready() {
-#if ! defined( WIN32 )  &&  ! defined(__APPLE__)
+#if defined( WIN32 ) || defined(__APPLE__)
+  // not used
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: you may need to handle timers here."
+#else // X11
   if (first_timeout) {
     elapse_timeouts();
     if (first_timeout->time <= 0) return 1;
@@ -780,6 +799,8 @@ void Fl::flush() {
 #elif defined (__APPLE_QUARTZ__)
   if (fl_gc)
     CGContextFlush(fl_gc);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: flush your graohics context here"
 #else
 # error unsupported platform
 #endif
@@ -978,6 +999,9 @@ void Fl::focus(Fl_Widget *o) {
 	  else if (x) // New WMs use the NETWM attribute:
 	    Fl_X::activate_window(x->xid);
 	}
+#elif defined(WIN32)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: handle platform specifics for change of keyboard focus here"
 #endif
 	fl_xfocus = win;
       }
@@ -1119,7 +1143,13 @@ void fl_throw_focus(Fl_Widget *o) {
 #endif // DEBUG
 
   if (o->contains(Fl::pushed())) Fl::pushed_ = 0;
-#if !(defined(WIN32) || defined(__APPLE__))
+#ifdef WIN32
+  // not used
+#elif defined(__APPLE__)
+  // not used
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: platform specific code when deleting a window"
+#else
   if (o->contains(fl_selection_requestor)) fl_selection_requestor = 0;
 #endif
   if (o->contains(Fl::belowmouse())) Fl::belowmouse_ = 0;
@@ -1627,6 +1657,8 @@ void Fl_Window::hide() {
   }
 #elif defined(__APPLE_QUARTZ__)
   ip->destroy();
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: code to destroy a window on screen"
 #else
 # error unsupported platform
 #endif
@@ -1659,6 +1691,8 @@ int Fl_Window::handle(int ev)
         XMapWindow(fl_display, fl_xid(this)); // extra map calls are harmless
 #elif defined(__APPLE_QUARTZ__)
 	i->map();
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: code to show a window on screen"
 #else
 # error unsupported platform
 #endif // __APPLE__
@@ -1681,6 +1715,8 @@ int Fl_Window::handle(int ev)
 	XUnmapWindow(fl_display, fl_xid(this));
 #elif defined(__APPLE_QUARTZ__)
 	i->unmap();
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: code to hide a window from screen"
 #else
 # error platform unsupported
 #endif
@@ -1867,6 +1903,8 @@ void Fl_Widget::damage(uchar fl, int X, int Y, int W, int H) {
         i->region->rects = (CGRect*)realloc(i->region->rects, (++(i->region->count)) * sizeof(CGRect));
         i->region->rects[i->region->count - 1] = arg;
       }
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: code to merge damage regions"
 #else
 # error unsupported platform
 #endif
diff --git a/src/Fl_Bitmap.cxx b/src/Fl_Bitmap.cxx
index da64c878e..42be41a77 100644
--- a/src/Fl_Bitmap.cxx
+++ b/src/Fl_Bitmap.cxx
@@ -150,6 +150,10 @@ void fl_delete_bitmask(Fl_Bitmask bm) {
 }
 
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement fl_create_bitmap"
+
 #else // X11 bitmask functions
 
 
@@ -262,8 +266,10 @@ int Fl_Bitmap::start(int XP, int YP, int WP, int HP, int &cx, int &cy,
   if (H <= 0) return 1;
 #if defined(WIN32)
   if (!id_) id_ = fl_create_bitmap(w(), h(), array);
-#else
+#elif defined(__APPLE__) || defined(USE_X11)
   if (!id_) id_ = fl_create_bitmask(w(), h(), array);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: call the right funtion to create a bitmap"
 #endif
   return 0;
 }
@@ -345,6 +351,10 @@ void Fl_GDI_Printer_Graphics_Driver::draw(Fl_Bitmap *bm, int XP, int YP, int WP,
   DeleteDC(tempdc);
 }  
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement Fl_Xlib_Graphics_Driver::draw()"
+
 #else // Xlib
 void Fl_Xlib_Graphics_Driver::draw(Fl_Bitmap *bm, int XP, int YP, int WP, int HP, int cx, int cy) {
   int X, Y, W, H;
@@ -375,8 +385,10 @@ void Fl_Bitmap::uncache() {
   if (id_) {
 #ifdef __APPLE_QUARTZ__
     fl_delete_bitmask((Fl_Bitmask)id_);
-#else
+#elif defined(WIN32) || defined(USE_X11)
     fl_delete_bitmask((Fl_Offscreen)id_);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: call the right funtion to create a bitmask"
 #endif
     id_ = 0;
   }
diff --git a/src/Fl_Copy_Surface.cxx b/src/Fl_Copy_Surface.cxx
index c14e0ce74..b1fe45725 100644
--- a/src/Fl_Copy_Surface.cxx
+++ b/src/Fl_Copy_Surface.cxx
@@ -97,6 +97,8 @@ Fl_Copy_Surface::Fl_Copy_Surface(int w, int h) :  Fl_Surface_Device(NULL)
     SetTextAlign(gc, TA_BASELINE|TA_LEFT);
     SetBkMode(gc, TRANSPARENT);
   } 
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: initialize memebrs of Fl_Copy_Surface"
 #else // Xlib
   helper = new Fl_Xlib_Surface_();
   driver(helper->driver());
@@ -133,6 +135,8 @@ Fl_Copy_Surface::~Fl_Copy_Surface()
   DeleteDC(gc);
   fl_gc = oldgc;
   delete (Fl_GDI_Surface_*)helper;
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: free resources in destructo of Fl_Copy_Surface"
 #else // Xlib
   fl_pop_clip(); 
   unsigned char *data = fl_read_image(NULL,0,0,width,height,0);
@@ -162,6 +166,8 @@ void Fl_Copy_Surface::set_current()
   fl_gc = gc;
   fl_window = (Window)1;
   Fl_Surface_Device::set_current();
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement Fl_Copy_Surface::set_current"
 #else
   fl_window=xid; 
   _ss = Fl_Surface_Device::surface(); 
diff --git a/src/Fl_Device.cxx b/src/Fl_Device.cxx
index a35227b23..7a487cd26 100644
--- a/src/Fl_Device.cxx
+++ b/src/Fl_Device.cxx
@@ -20,6 +20,12 @@
 #include <FL/Fl_Device.H>
 #include <FL/Fl_Image.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: instantiate and implement various device drivers here"
+#else
+#endif
+
 const char *Fl_Device::class_id = "Fl_Device";
 const char *Fl_Surface_Device::class_id = "Fl_Surface_Device";
 const char *Fl_Display_Device::class_id = "Fl_Display_Device";
@@ -86,6 +92,8 @@ Fl_Display_Device *Fl_Display_Device::display_device() {
                                                                   Fl_Quartz_Graphics_Driver
 #elif defined(WIN32)
                                                                   Fl_GDI_Graphics_Driver
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: instantiate your display driver here"
 #else
                                                                   Fl_Xlib_Graphics_Driver
 #endif
diff --git a/src/Fl_Double_Window.cxx b/src/Fl_Double_Window.cxx
index 83af44b62..397507a95 100644
--- a/src/Fl_Double_Window.cxx
+++ b/src/Fl_Double_Window.cxx
@@ -108,6 +108,8 @@ void fl_copy_offscreen(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx
     ((Fl_GDI_Graphics_Driver*)fl_graphics_driver)->copy_offscreen(x, y, w, h, pixmap, srcx, srcy);
 #elif defined(__APPLE__)
     ((Fl_Quartz_Graphics_Driver*)fl_graphics_driver)->copy_offscreen(x, y, w, h, pixmap, srcx, srcy);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: call our version of fl_copy_offscreen"
 #endif
   }
   else { // when copy is not to the display
@@ -379,6 +381,7 @@ void fl_end_offscreen() {
 
 
 #else
+# pragma message "FL_PORTING: implement offscreen render space generation and management"
 # error unsupported platform
 #endif
 
@@ -416,6 +419,7 @@ void Fl_Double_Window::flush(int eraseoverlay) {
       clear_damage(FL_DAMAGE_ALL);
     }
 #else
+# pragma message "FL_PORTING: call a function to clear any graphics port damage flags"
 # error unsupported platform
 #endif
   }
@@ -467,6 +471,8 @@ void Fl_Double_Window::flush(int eraseoverlay) {
     } else {
       draw();
     }
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: manage double buffered drawing"
 #else // X:
     fl_window = myi->other_xid;
     draw();
diff --git a/src/Fl_File_Browser.cxx b/src/Fl_File_Browser.cxx
index 17ff1afbd..a1a114f76 100644
--- a/src/Fl_File_Browser.cxx
+++ b/src/Fl_File_Browser.cxx
@@ -26,6 +26,12 @@
 //   Fl_File_Browser::filter()          - Set the filename filter.
 //
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the iternals of your file browser here"
+#else
+#endif
+
 //
 // Include necessary header files...
 //
diff --git a/src/Fl_File_Chooser2.cxx b/src/Fl_File_Chooser2.cxx
index 6527a77dd..756aedf73 100644
--- a/src/Fl_File_Chooser2.cxx
+++ b/src/Fl_File_Chooser2.cxx
@@ -357,6 +357,12 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the internal of your filechooser here"
+#else
+#endif
+
 #if defined(WIN32) && ! defined (__CYGWIN__)
 #  include <direct.h>
 #  include <io.h>
diff --git a/src/Fl_File_Icon.cxx b/src/Fl_File_Icon.cxx
index 3d35e10e4..4c8cf2367 100644
--- a/src/Fl_File_Icon.cxx
+++ b/src/Fl_File_Icon.cxx
@@ -51,6 +51,11 @@
 #include <FL/fl_draw.H>
 #include <FL/filename.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement file type interpretation here"
+#else
+#endif
 
 //
 // Define missing POSIX/XPG4 macros as needed...
diff --git a/src/Fl_Font.H b/src/Fl_Font.H
index 7a98650b2..561f249a2 100644
--- a/src/Fl_Font.H
+++ b/src/Fl_Font.H
@@ -26,6 +26,13 @@
 
 #include <config.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement font descriptor details here"
+#else
+#endif
+
+
 #  if USE_XFT
 typedef struct _XftFont XftFont;
 #  elif !defined(WIN32) && !defined(__APPLE__)
@@ -65,6 +72,8 @@ public:
   //const char* encoding;
   int angle;
   FL_EXPORT Fl_Font_Descriptor(const char* xfontname, Fl_Fontsize size, int angle);
+#  elif defined(FL_PORTING)
+#    pragma message "FL_PORTING: define variables and storage types for font handling"
 #  else
   XUtf8FontStruct* font;	// X UTF-8 font information
   FL_EXPORT Fl_Font_Descriptor(const char* xfontname);
@@ -87,15 +96,28 @@ struct Fl_Fontdesc {
   const char *name;
   char fontname[128];	// "Pretty" font name
   Fl_Font_Descriptor *first;	// linked list of sizes of this style
-#  ifndef WIN32
+#ifdef WIN32
+#elif defined(__APPLE__)
   char **xlist;		// matched X font names
   int n;		// size of xlist, negative = don't free xlist!
-#  endif
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: do you need additional storage in Fl_Fontdesc?"
+#else
+  char **xlist;		// matched X font names
+  int n;		// size of xlist, negative = don't free xlist!
+#endif
 };
 
 extern FL_EXPORT Fl_Fontdesc *fl_fonts; // the table
 
-#  ifndef WIN32
+#ifdef WIN32
+#elif defined(__APPLE__)
+// functions for parsing X font names:
+FL_EXPORT const char* fl_font_word(const char *p, int n);
+FL_EXPORT char *fl_find_fontsize(char *name);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: do you need additional functions for font handling?"
+#else
 // functions for parsing X font names:
 FL_EXPORT const char* fl_font_word(const char *p, int n);
 FL_EXPORT char *fl_find_fontsize(char *name);
diff --git a/src/Fl_Gl_Choice.H b/src/Fl_Gl_Choice.H
index 2d5e2fcb9..69d388607 100644
--- a/src/Fl_Gl_Choice.H
+++ b/src/Fl_Gl_Choice.H
@@ -45,6 +45,12 @@
 #ifndef Fl_Gl_Choice_H
 #define Fl_Gl_Choice_H
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to list and select OpenGL drawing contexts"
+#else
+#endif
+
 // Warning: whatever GLContext is defined to must take exactly the same
 // space in a structure as a void*!!!
 #ifdef WIN32
@@ -77,6 +83,8 @@ public:
   PIXELFORMATDESCRIPTOR pfd; // some wgl calls need this thing
 #elif defined(__APPLE_QUARTZ__)
   NSOpenGLPixelFormat* pixelformat;
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define OpenGL pixel format containers"
 #else
   XVisualInfo *vis;	// the visual to use
   Colormap colormap;	// a colormap for that visual
@@ -97,6 +105,10 @@ GLContext fl_create_gl_context(Fl_Window*, const Fl_Gl_Choice*, int layer=0);
 
 GLContext fl_create_gl_context(Fl_Window*, const Fl_Gl_Choice*, int layer=0);
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: define fl_create_gl_context function"
+
 #else
 
 GLContext fl_create_gl_context(XVisualInfo* vis);
diff --git a/src/Fl_Gl_Choice.cxx b/src/Fl_Gl_Choice.cxx
index edb0843f2..1af0b355d 100644
--- a/src/Fl_Gl_Choice.cxx
+++ b/src/Fl_Gl_Choice.cxx
@@ -27,6 +27,12 @@
 #  include "flstring.h"
 #  include <FL/fl_utf8.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to list and select OpenGL drawing contexts"
+#else
+#endif
+
 #  ifdef WIN32
 void fl_save_dc(HWND, HDC);
 #elif defined(__APPLE__)
diff --git a/src/Fl_Gl_Device_Plugin.cxx b/src/Fl_Gl_Device_Plugin.cxx
index 94c355349..a7dfcd0a6 100644
--- a/src/Fl_Gl_Device_Plugin.cxx
+++ b/src/Fl_Gl_Device_Plugin.cxx
@@ -23,6 +23,12 @@
 #include <FL/Fl_RGB_Image.H>
 #include "FL/Fl.H"
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement code to read OpenGL renderings into RGB maps"
+#else
+#endif
+
 #if defined(__APPLE__)
 uchar *convert_BGRA_to_RGB(uchar *baseAddress, int w, int h, int mByteWidth)
 {
diff --git a/src/Fl_Gl_Overlay.cxx b/src/Fl_Gl_Overlay.cxx
index 76d532b89..204a0796e 100644
--- a/src/Fl_Gl_Overlay.cxx
+++ b/src/Fl_Gl_Overlay.cxx
@@ -25,6 +25,12 @@
 #include <FL/Fl_Gl_Window.H>
 #include <stdlib.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement OpenGL hardware overlays if they are availbale in a compatible way. This is rarely needed."
+#else
+#endif
+
 #if !HAVE_GL_OVERLAY
 
 int Fl_Gl_Window::can_do_overlay() {return 0;}
diff --git a/src/Fl_Gl_Window.cxx b/src/Fl_Gl_Window.cxx
index 46e7ebbb7..02d238332 100644
--- a/src/Fl_Gl_Window.cxx
+++ b/src/Fl_Gl_Window.cxx
@@ -32,6 +32,12 @@ extern int fl_gl_load_plugin;
 #include <stdlib.h>
 #include <FL/fl_utf8.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the creation and destruction of OpenGL surfaces"
+#else
+#endif
+
 ////////////////////////////////////////////////////////////////
 
 // The symbol SWAP_TYPE defines what is in the back buffer after doing
diff --git a/src/Fl_Image.cxx b/src/Fl_Image.cxx
index 8891c7fb7..cc28fdb89 100644
--- a/src/Fl_Image.cxx
+++ b/src/Fl_Image.cxx
@@ -25,6 +25,12 @@
 #include <FL/Fl_Printer.H>
 #include "flstring.h"
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement RGB image handling here"
+#else
+#endif
+
 #ifdef WIN32
 void fl_release_dc(HWND, HDC); // from Fl_win32.cxx
 #endif
diff --git a/src/Fl_Image_Surface.cxx b/src/Fl_Image_Surface.cxx
index 347ce3a2a..c7303fb27 100644
--- a/src/Fl_Image_Surface.cxx
+++ b/src/Fl_Image_Surface.cxx
@@ -20,6 +20,11 @@
 #include <FL/Fl_Printer.H>
 #include <FL/Fl.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement image surface handling here"
+#else
+#endif
 
 const char *Fl_Image_Surface::class_id = "Fl_Image_Surface";
 
diff --git a/src/Fl_Input.cxx b/src/Fl_Input.cxx
index a7232117e..ae46e7797 100644
--- a/src/Fl_Input.cxx
+++ b/src/Fl_Input.cxx
@@ -22,6 +22,13 @@
 // In theory you can replace this code with another subclass to change
 // the keybindings.
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: implement text input specifics here"
+  // current custom code is for OS X keybaord specifics only
+#else
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <FL/Fl.H>
diff --git a/src/Fl_Input_.cxx b/src/Fl_Input_.cxx
index f7d739889..9f926d83e 100644
--- a/src/Fl_Input_.cxx
+++ b/src/Fl_Input_.cxx
@@ -27,6 +27,13 @@
 #include <stdlib.h>
 #include <ctype.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: manage character composing here"
+#else
+#endif
+
+
 #define MAXBUF 1024
 #if defined(USE_X11) && !USE_XFT
 const int secret_char = '*'; // asterisk to hide secret input
diff --git a/src/Fl_Native_File_Chooser.cxx b/src/Fl_Native_File_Chooser.cxx
index 7aa1d799b..37fa49dfc 100644
--- a/src/Fl_Native_File_Chooser.cxx
+++ b/src/Fl_Native_File_Chooser.cxx
@@ -19,15 +19,16 @@
 // Use Windows' chooser
 #ifdef WIN32
 #include "Fl_Native_File_Chooser_WIN32.cxx"
-#endif
 
 // Use Apple's chooser
-#ifdef __APPLE__
+#elif defined(__APPLE__)
 #include <FL/Fl_Native_File_Chooser.H>
-#endif
+
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the native file chooser interface"
 
 // All else falls back to FLTK's own chooser
-#if ! defined(__APPLE__) && !defined(WIN32)
+#else
 #include "Fl_Native_File_Chooser_FLTK.cxx"
 #endif
 
diff --git a/src/Fl_Pixmap.cxx b/src/Fl_Pixmap.cxx
index 30d51d5a9..2953727bf 100644
--- a/src/Fl_Pixmap.cxx
+++ b/src/Fl_Pixmap.cxx
@@ -32,6 +32,12 @@
 #include <FL/Fl_Pixmap.H>
 #include <FL/Fl_Printer.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: this file needs a lot of custom code to draw Pixmaps correctly"
+#else
+#endif
+
 #if defined(USE_X11)
 #  if HAVE_X11_XREGION_H
 #    include <X11/Xregion.h>
diff --git a/src/Fl_Preferences.cxx b/src/Fl_Preferences.cxx
index 90b7820fd..47c842f66 100644
--- a/src/Fl_Preferences.cxx
+++ b/src/Fl_Preferences.cxx
@@ -29,6 +29,12 @@
 #include <sys/stat.h>
 #include <time.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement some file storage in a designated place"
+#else
+#endif
+
 #if defined(WIN32) && !defined(__CYGWIN__)
 #  include <windows.h>
 #  include <direct.h>
diff --git a/src/Fl_Printer.cxx b/src/Fl_Printer.cxx
index be081ad7d..e04c3b97e 100644
--- a/src/Fl_Printer.cxx
+++ b/src/Fl_Printer.cxx
@@ -19,6 +19,12 @@
 
 #include <FL/Fl_Printer.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the printer device specifics"
+#else
+#endif
+
 #if defined(WIN32)
 #include "Fl_GDI_Printer.cxx"
 #endif
diff --git a/src/Fl_Text_Display.cxx b/src/Fl_Text_Display.cxx
index d747b1c2c..c5c8b7b61 100644
--- a/src/Fl_Text_Display.cxx
+++ b/src/Fl_Text_Display.cxx
@@ -31,6 +31,12 @@
 #include <FL/Fl_Text_Display.H>
 #include <FL/Fl_Window.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: look out for some code that visualizes character composing"
+#else
+#endif
+
 #undef min
 #undef max
 
diff --git a/src/Fl_Text_Editor.cxx b/src/Fl_Text_Editor.cxx
index 891f162bf..1a8288bfb 100644
--- a/src/Fl_Text_Editor.cxx
+++ b/src/Fl_Text_Editor.cxx
@@ -25,6 +25,11 @@
 #include <FL/Fl_Text_Editor.H>
 #include <FL/fl_ask.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add common shortcut for your platform here"
+#else
+#endif
 
 /* Keyboard Control Matrix
 
diff --git a/src/Fl_Window_iconize.cxx b/src/Fl_Window_iconize.cxx
index 3d9546c85..73dc0edfc 100644
--- a/src/Fl_Window_iconize.cxx
+++ b/src/Fl_Window_iconize.cxx
@@ -29,6 +29,8 @@ void Fl_Window::iconize() {
     ShowWindow(i->xid, SW_SHOWMINNOACTIVE);
 #elif defined(__APPLE__)
     i->collapse();
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to iconify a window"
 #else
     XIconifyWindow(fl_display, i->xid, fl_screen);
 #endif
diff --git a/src/Fl_Window_shape.cxx b/src/Fl_Window_shape.cxx
index c838eab0f..ff36eac13 100644
--- a/src/Fl_Window_shape.cxx
+++ b/src/Fl_Window_shape.cxx
@@ -24,6 +24,12 @@
 #include <FL/Fl_Pixmap.H>
 #include <string.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to implement arbitrarily shaped windows"
+#else
+#endif
+
 #ifdef WIN32
 # include <malloc.h> // needed for VisualC2010
 #elif !defined(__APPLE__)
diff --git a/src/Fl_abort.cxx b/src/Fl_abort.cxx
index c1b121408..fc2e40541 100644
--- a/src/Fl_abort.cxx
+++ b/src/Fl_abort.cxx
@@ -26,6 +26,12 @@
 #include <stdarg.h>
 #include "flstring.h"
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: use native message box below if one is available"
+#else
+#endif
+
 #ifdef WIN32
 #  include <windows.h>
 
diff --git a/src/Fl_arg.cxx b/src/Fl_arg.cxx
index 184f52fc9..1fec33b69 100644
--- a/src/Fl_arg.cxx
+++ b/src/Fl_arg.cxx
@@ -29,6 +29,12 @@
 #include "flstring.h"
 
 #if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement special command line handling"
+#else
+#endif
+
+#if defined(WIN32) || defined(__APPLE__)
 int XParseGeometry(const char*, int*, int*, unsigned int*, unsigned int*);
 #  define NoValue	0x0000
 #  define XValue  	0x0001
diff --git a/src/Fl_compose.cxx b/src/Fl_compose.cxx
index 646be1b71..b10b0b72f 100644
--- a/src/Fl_compose.cxx
+++ b/src/Fl_compose.cxx
@@ -21,6 +21,11 @@
 Utility functions to support text input.
 */
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement keyboard composing in the code below"
+#else
+#endif
 
 #include <FL/Fl.H>
 #include <FL/x.H>
diff --git a/src/Fl_display.cxx b/src/Fl_display.cxx
index fd942d8a3..dc179b0b6 100644
--- a/src/Fl_display.cxx
+++ b/src/Fl_display.cxx
@@ -32,6 +32,8 @@
 void Fl::display(const char *d) {
 #if defined(__APPLE__) || defined(WIN32)
   (void)d;
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: initiate a connection to the display"
 #else
   static char e[1024];
   strcpy(e,"DISPLAY=");
diff --git a/src/Fl_get_key.cxx b/src/Fl_get_key.cxx
index 4e7d6c649..af7117fdf 100644
--- a/src/Fl_get_key.cxx
+++ b/src/Fl_get_key.cxx
@@ -20,6 +20,8 @@
 #  include "Fl_get_key_win32.cxx"
 #elif defined(__APPLE__)
 #  include "Fl_get_key_mac.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement keyboard reading and interpretation in its own file"
 #else
 
 // Return the current state of a key.  This is the X version.  I identify
diff --git a/src/Fl_get_system_colors.cxx b/src/Fl_get_system_colors.cxx
index c0385d53f..2c628f88b 100644
--- a/src/Fl_get_system_colors.cxx
+++ b/src/Fl_get_system_colors.cxx
@@ -200,6 +200,10 @@ void Fl::get_system_colors()
 #endif
 }
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement code to find the current desktop color scheme"
+
 #else						// --- X11 ---
 
 // Read colors that KDE writes to the xrdb database.
diff --git a/src/Fl_grab.cxx b/src/Fl_grab.cxx
index c8f7ac941..9b0446d74 100644
--- a/src/Fl_grab.cxx
+++ b/src/Fl_grab.cxx
@@ -30,6 +30,12 @@
 
 extern void fl_fix_focus(); // in Fl.cxx
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: tell a window to grab all following events"
+#else
+#endif
+
 #ifdef WIN32
 // We have to keep track of whether we have captured the mouse, since
 // MSWindows shows little respect for this... Grep for fl_capture to
diff --git a/src/Fl_lock.cxx b/src/Fl_lock.cxx
index bef9d972d..fc6daf8b9 100644
--- a/src/Fl_lock.cxx
+++ b/src/Fl_lock.cxx
@@ -389,6 +389,10 @@ void lock_ring() {
   pthread_mutex_lock(ring_mutex);
 }
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement simple locking and unlocking for basic multithreading support"
+
 #else
 
 void unlock_ring() {
diff --git a/src/Fl_own_colormap.cxx b/src/Fl_own_colormap.cxx
index 1c57870b3..d9eee2bb2 100644
--- a/src/Fl_own_colormap.cxx
+++ b/src/Fl_own_colormap.cxx
@@ -45,6 +45,11 @@ void Fl::own_colormap() {}
 // MacOS X always provides a TrueColor interface...
 
 void Fl::own_colormap() {}
+
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: implement color map handling if you don;t have an RGB screen"
+
 #else
 // X version
 
diff --git a/src/Fl_visual.cxx b/src/Fl_visual.cxx
index c9df1a19a..75dc2cbc8 100644
--- a/src/Fl_visual.cxx
+++ b/src/Fl_visual.cxx
@@ -73,6 +73,9 @@ int Fl::visual(int flags) {
   return 1;
 }
 
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to handle RGB and color index visuals"
+
 #else
 
 #if USE_XDBE
diff --git a/src/Fl_x.cxx b/src/Fl_x.cxx
index 7bb8761f2..5422735b5 100644
--- a/src/Fl_x.cxx
+++ b/src/Fl_x.cxx
@@ -20,6 +20,8 @@
 //#  include "Fl_win32.cxx"
 #elif defined(__APPLE__)
 //#  include "Fl_mac.cxx"	// now Fl_cocoa.mm
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement the FLTK core in its own file"
 #elif !defined(FL_DOXYGEN)
 
 #  define CONSOLIDATE_MOTION 1
diff --git a/src/filename_ext.cxx b/src/filename_ext.cxx
index dc68b302d..406420e07 100644
--- a/src/filename_ext.cxx
+++ b/src/filename_ext.cxx
@@ -20,6 +20,13 @@
 
 #include <FL/filename.H>
 
+#ifdef WIN32
+#elif defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement directory and filename handling for your platfomr if needed"
+#else // X11
+#endif
+
 /** Gets the extensions of a filename.
    \code
    #include <FL/filename.H>
diff --git a/src/filename_isdir.cxx b/src/filename_isdir.cxx
index 492938ffd..e27c0ee37 100644
--- a/src/filename_isdir.cxx
+++ b/src/filename_isdir.cxx
@@ -25,6 +25,12 @@
 #include <FL/filename.H>
 #include <FL/fl_utf8.h>
 
+#ifdef WIN32
+#elif defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement directory and filename handling for your platfomr if needed"
+#else // X11
+#endif
 
 #if defined(WIN32) || defined(__EMX__) && !defined(__CYGWIN__)
 static inline int isdirsep(char c) {return c=='/' || c=='\\';}
diff --git a/src/filename_list.cxx b/src/filename_list.cxx
index 4b811795f..d65ddcdd3 100644
--- a/src/filename_list.cxx
+++ b/src/filename_list.cxx
@@ -26,6 +26,13 @@
 #include <FL/x.H>
 #endif
 
+#ifdef WIN32
+#elif defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement directory and filename handling for your platfomr if needed"
+#else // X11
+#endif
+
 extern "C" {
 #ifndef HAVE_SCANDIR
   int fl_scandir (const char *dir, dirent ***namelist,
diff --git a/src/fl_arci.cxx b/src/fl_arci.cxx
index 13ce0240d..ac3b839fb 100644
--- a/src/fl_arci.cxx
+++ b/src/fl_arci.cxx
@@ -69,6 +69,7 @@ void Fl_Graphics_Driver::arc(int x,int y,int w,int h,double a1,double a2) {
   CGContextStrokePath(fl_gc);
   CGContextSetShouldAntialias(fl_gc, false);
 #else
+# pragma message "FL_PORTING: implement arc drawing"
 # error unsupported platform
 #endif
 }
@@ -114,6 +115,7 @@ void Fl_Graphics_Driver::pie(int x,int y,int w,int h,double a1,double a2) {
   CGContextFillPath(fl_gc);
   CGContextSetShouldAntialias(fl_gc, false);
 #else
+# pragma message "FL_PORTING: implement pie drawing (mmmh, apple pie)"
 # error unsupported platform
 #endif
 }
diff --git a/src/fl_ask.cxx b/src/fl_ask.cxx
index b24a1762b..ce61a2796 100644
--- a/src/fl_ask.cxx
+++ b/src/fl_ask.cxx
@@ -309,6 +309,8 @@ void fl_beep(int type) {
     default :
       break;
   }
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement beeping or other noise generating functions"
 #else
   switch (type) {
     case FL_BEEP_DEFAULT :
diff --git a/src/fl_call_main.c b/src/fl_call_main.c
index f32122a20..1d4b8c1c0 100644
--- a/src/fl_call_main.c
+++ b/src/fl_call_main.c
@@ -37,6 +37,12 @@
  * Microsoft(r) Windows(r) that allows for it.
  */
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement 'main()' here if your platform provides another app entry point"
+#else
+#endif
+
 #if defined(WIN32) && !defined(FL_DLL) && !defined (__GNUC__)
 
 #  include <windows.h>
diff --git a/src/fl_color.cxx b/src/fl_color.cxx
index 6b03bb159..38e09242e 100644
--- a/src/fl_color.cxx
+++ b/src/fl_color.cxx
@@ -27,6 +27,8 @@
 #  include "fl_color_win32.cxx"
 #elif defined(__APPLE__)
 #  include "fl_color_mac.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement color handling in your own file based on fl_color.cxx"
 #else
 
 // Also code to look at the X visual and figure out the best way to turn
diff --git a/src/fl_dnd.cxx b/src/fl_dnd.cxx
index 4da6c91a2..cee05eab5 100644
--- a/src/fl_dnd.cxx
+++ b/src/fl_dnd.cxx
@@ -20,6 +20,8 @@
 #  include "fl_dnd_win32.cxx"
 #elif defined(__APPLE__)
 //#  include "fl_dnd_mac.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement drag and drop in its own platform file"
 #else
 #  include "fl_dnd_x.cxx"
 #endif
diff --git a/src/fl_draw_image.cxx b/src/fl_draw_image.cxx
index 8c17f010f..7312061c5 100644
--- a/src/fl_draw_image.cxx
+++ b/src/fl_draw_image.cxx
@@ -30,6 +30,8 @@
 #  include "fl_draw_image_win32.cxx"
 #elif defined(__APPLE__)
 #  include "fl_draw_image_mac.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement image drawing in its own file"
 #else
 
 // A list of assumptions made about the X display:
diff --git a/src/fl_draw_pixmap.cxx b/src/fl_draw_pixmap.cxx
index ff5f1985f..a5b29e4b7 100644
--- a/src/fl_draw_pixmap.cxx
+++ b/src/fl_draw_pixmap.cxx
@@ -38,6 +38,12 @@
 #include <stdio.h>
 #include "flstring.h"
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement platform specific about pixmap drawing here"
+#else
+#endif
+
 static int ncolors, chars_per_pixel;
 
 /**
diff --git a/src/fl_font.cxx b/src/fl_font.cxx
index 26960e081..f8feba035 100644
--- a/src/fl_font.cxx
+++ b/src/fl_font.cxx
@@ -51,6 +51,8 @@
 #  include "fl_font_mac.cxx"
 #elif USE_XFT
 #  include "fl_font_xft.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement font handling specific in its own file"
 #else
 #  include "fl_font_x.cxx"
 #endif // WIN32
diff --git a/src/fl_line_style.cxx b/src/fl_line_style.cxx
index 40274d314..14965e4fd 100644
--- a/src/fl_line_style.cxx
+++ b/src/fl_line_style.cxx
@@ -155,6 +155,7 @@ void Fl_Graphics_Driver::line_style(int style, int width, char* dashes) {
   }
   fl_quartz_restore_line_style_();
 #else
+# pragma message "FL_PORTING: implement line styles here"
 # error unsupported platform
 #endif
 }
diff --git a/src/fl_open_uri.cxx b/src/fl_open_uri.cxx
index d25b5b9a9..bfc31355f 100644
--- a/src/fl_open_uri.cxx
+++ b/src/fl_open_uri.cxx
@@ -142,6 +142,9 @@ fl_open_uri(const char *uri, char *msg, int msglen) {
 
   return run_program("/usr/bin/open", argv, msg, msglen) != 0;
 
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: add code to open any file type with an external app"
+
 #else // !WIN32 && !__APPLE__
   // Run any of several well-known commands to open the URI.
   //
diff --git a/src/fl_read_image.cxx b/src/fl_read_image.cxx
index 89ff3e49e..f42fc6804 100644
--- a/src/fl_read_image.cxx
+++ b/src/fl_read_image.cxx
@@ -25,6 +25,12 @@
 #  include <stdio.h>
 #endif // DEBUG
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement code to read RGB data from screen"
+#else
+#endif
+
 #if defined(__APPLE__)
 #  include "fl_read_image_mac.cxx"
 #else
diff --git a/src/fl_rect.cxx b/src/fl_rect.cxx
index ff217db34..29d36abce 100644
--- a/src/fl_rect.cxx
+++ b/src/fl_rect.cxx
@@ -33,6 +33,12 @@
 #include <FL/fl_draw.H>
 #include <FL/x.H>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement al the line drawing functions below"
+#else
+#endif
+
 // fl_line_width_ must contain the absolute value of the current
 // line width to be used for X11 clipping (see below).
 // This is defined in src/fl_line_style.cxx
diff --git a/src/fl_scroll_area.cxx b/src/fl_scroll_area.cxx
index eecf1847a..3203e2c60 100644
--- a/src/fl_scroll_area.cxx
+++ b/src/fl_scroll_area.cxx
@@ -151,6 +151,7 @@ void fl_scroll(int X, int Y, int W, int H, int dx, int dy,
     CFRelease(img);
     }
 #else
+# pragma message "FL_PORTING: implement scrolling of the screen contents"
 # error unsupported platform
 #endif
   if (dx) draw_area(data, clip_x, dest_y, clip_w, src_h);
diff --git a/src/fl_set_fonts.cxx b/src/fl_set_fonts.cxx
index 000d5701a..2673a78fd 100644
--- a/src/fl_set_fonts.cxx
+++ b/src/fl_set_fonts.cxx
@@ -28,6 +28,8 @@
 #  include "fl_set_fonts_mac.cxx"
 #elif USE_XFT
 #  include "fl_set_fonts_xft.cxx"
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement changes in font in its own file"
 #else
 #  include "fl_set_fonts_x.cxx"
 #endif // WIN32
diff --git a/src/fl_shortcut.cxx b/src/fl_shortcut.cxx
index f9defc2f9..dc346c46f 100644
--- a/src/fl_shortcut.cxx
+++ b/src/fl_shortcut.cxx
@@ -42,6 +42,12 @@
 #include <FL/x.H>
 #endif
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement keyboard shortcut handling here"
+#else
+#endif
+
 /**
   Tests the current event, which must be an FL_KEYBOARD or
   FL_SHORTCUT, against a shortcut value (described in Fl_Button).
diff --git a/src/fl_utf.c b/src/fl_utf.c
index 46d13959d..d81ba983d 100644
--- a/src/fl_utf.c
+++ b/src/fl_utf.c
@@ -22,6 +22,12 @@
 #include <string.h>
 #include <stdlib.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: llok out for some unicode functions here. Default should be fine though."
+#else
+#endif
+
 /** \addtogroup fl_unicode
     @{
 */
diff --git a/src/fl_utf8.cxx b/src/fl_utf8.cxx
index d1ce2d80c..e1375d84f 100644
--- a/src/fl_utf8.cxx
+++ b/src/fl_utf8.cxx
@@ -21,6 +21,12 @@
 #include <FL/filename.H>
 #include <stdarg.h>
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: verify code for utf8 handling"
+#else
+#endif
+
 #if defined(WIN32) || defined(__CYGWIN__)
 # include <ctype.h>
 # include <io.h>
diff --git a/src/fl_vertex.cxx b/src/fl_vertex.cxx
index d665ae4e4..c44178eba 100644
--- a/src/fl_vertex.cxx
+++ b/src/fl_vertex.cxx
@@ -28,6 +28,12 @@
 // matt: the Quartz implementation purposely doesn't use the Quartz matrix
 //       operations for reasons of compatibility and maintainability
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement functions below for vector drawing"
+#else
+#endif
+
 #include <config.h>
 #include <FL/fl_draw.H>
 #include <FL/x.H>
diff --git a/src/forms_timer.cxx b/src/forms_timer.cxx
index 39da25403..bf8b526d9 100644
--- a/src/forms_timer.cxx
+++ b/src/forms_timer.cxx
@@ -52,6 +52,8 @@ void fl_gettime(long* sec, long* usec) {
   *sec = (long) tp.time;
   *usec = tp.millitm * 1000;
 # endif
+#elif defined(FL_PORTING) && !defined(__APPLE__)
+#  pragma message "FL_PORTING: implement time, rarely needed, if ever."
 #else
   struct timeval tp;
   struct timezone tzp;
diff --git a/src/gl_draw.cxx b/src/gl_draw.cxx
index 1c31f4174..2d501e741 100644
--- a/src/gl_draw.cxx
+++ b/src/gl_draw.cxx
@@ -19,6 +19,12 @@
 // Functions from <FL/gl.h>
 // See also Fl_Gl_Window and gl_start.cxx
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: implement OpenGL text rendering here"
+#else
+#endif
+
 #include "flstring.h"
 #if HAVE_GL || defined(FL_DOXYGEN)
 
diff --git a/src/gl_start.cxx b/src/gl_start.cxx
index 7e2bee25c..0ea02b1d1 100644
--- a/src/gl_start.cxx
+++ b/src/gl_start.cxx
@@ -28,6 +28,12 @@
 // be erased when the buffers are swapped (when double buffer hardware
 // is being used)
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: if possible, add OpenGL rendering in non-OpenGL contexts"
+#else
+#endif
+
 #include <config.h>
 #if HAVE_GL
 
diff --git a/src/screen_xywh.cxx b/src/screen_xywh.cxx
index f470ec3eb..3cf2be42b 100644
--- a/src/screen_xywh.cxx
+++ b/src/screen_xywh.cxx
@@ -142,6 +142,10 @@ static void screen_init() {
   num_screens = count;
 }
 
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: return various information about the screens in the system"
+
 #else
 
 #if HAVE_XINERAMA
diff --git a/src/xutf8/is_right2left.c b/src/xutf8/is_right2left.c
index 69a612a48..19685ad5c 100644
--- a/src/xutf8/is_right2left.c
+++ b/src/xutf8/is_right2left.c
@@ -14,6 +14,12 @@
  *     http://www.fltk.org/str.php
  */
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: utf8 functionality"
+#else
+#endif
+
 /*
  * This file is required on all platforms for utf8 support
  */
diff --git a/src/xutf8/lcUniConv/cp936ext.h b/src/xutf8/lcUniConv/cp936ext.h
index e41db3f5d..765a15a8b 100644
--- a/src/xutf8/lcUniConv/cp936ext.h
+++ b/src/xutf8/lcUniConv/cp936ext.h
@@ -16,7 +16,15 @@
  *     http://www.fltk.org/str.php
  */
 
-#if !defined(WIN32) && !defined(__APPLE__)
+#if defined(WIN32) || defined(__APPLE__)
+
+  // not needed
+
+#elif defined(FL_PORTING)
+
+#  pragma message "FL_PORTING: include the character encoding file below if needed"
+
+#else
 
 #ifndef CP936
 #ifdef NEED_TOWC
diff --git a/src/xutf8/utf8Utils.c b/src/xutf8/utf8Utils.c
index 54bbccf4c..17d49d34c 100644
--- a/src/xutf8/utf8Utils.c
+++ b/src/xutf8/utf8Utils.c
@@ -14,6 +14,12 @@
  *     http://www.fltk.org/str.php
  */
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: utf8"
+#else
+#endif
+
 /*
  * Unicode to UTF-8 conversion functions.
  */
diff --git a/src/xutf8/utf8Wrap.c b/src/xutf8/utf8Wrap.c
index 7b52c0e5e..32619fe0a 100644
--- a/src/xutf8/utf8Wrap.c
+++ b/src/xutf8/utf8Wrap.c
@@ -14,6 +14,12 @@
  *     http://www.fltk.org/str.php
  */
 
+#if defined(WIN32) || defined(__APPLE__)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: utf8"
+#else
+#endif
+
 /*
  * X11 UTF-8 text drawing functions.
  */