diff --git a/src/buttons.c b/src/buttons.c
index d3fbb729..801dad1f 100644
--- a/src/buttons.c
+++ b/src/buttons.c
@@ -762,6 +762,15 @@ const T_Lookup Lookup_MouseSpeed[] = {
   {NULL,-1},
 };
 
+const T_Lookup Lookup_SwapButtons[] = {
+  {"None",0},
+  {"Shift",MOD_SHIFT},
+  {"Control",MOD_CTRL},
+  {"Alt",MOD_ALT},
+  {"Meta",MOD_META},
+  {NULL,-1},
+};
+
 typedef struct {
   const char* Label;
   byte Type; // 0: label, 1+: setting (size in bytes) 
@@ -920,7 +929,6 @@ void Button_Settings(void)
   T_Setting setting[SETTING_PER_PAGE*SETTING_PAGES] = {
   
   {"           --- GUI  ---",0,NULL,0,0,0,NULL},
-  {"",0,NULL,0,0,0,NULL},
   {"Opening message:",1,&(selected_config.Opening_message),0,1,0,Lookup_YesNo},
   {"Menu ratio adapt:",1,&(selected_config.Ratio),0,1,0,Lookup_MenuRatio},
   {"Draw limits:",1,&(selected_config.Display_image_limits),0,1,0,Lookup_YesNo},
@@ -930,9 +938,9 @@ void Button_Settings(void)
   {"Grid XOR color:",1,&(selected_config.Grid_XOR_color),0,255,3,NULL},
   {"Sync views:",1,&(selected_config.Sync_views),0,1,0,Lookup_YesNo},
   {"",0,NULL,0,0,0,NULL},
+  {"",0,NULL,0,0,0,NULL},
   
   {"           --- Input  ---",0,NULL,0,0,0,NULL},
-  {"",0,NULL,0,0,0,NULL},
   {"Scrollbar speed",0,NULL,0,0,0,NULL},
   {"  on left click:",1,&(selected_config.Delay_left_click_on_slider),1,255,4,NULL},
   {"  on right click:",1,&(selected_config.Delay_right_click_on_slider),1,255,4,NULL},
@@ -942,9 +950,9 @@ void Button_Settings(void)
   {"Mouse speed (fullscreen)",0,NULL,0,0,0,NULL},
   {"  horizontally:",1,&(selected_config.Mouse_sensitivity_index_x),1,4,0,Lookup_MouseSpeed},
   {"  vertically:",1,&(selected_config.Mouse_sensitivity_index_y),1,4,0,Lookup_MouseSpeed},
+  {"Key to swap buttons:",2,&(selected_config.Swap_buttons),0,0,0,Lookup_SwapButtons},
   
   {"          --- Editing  ---",0,NULL,0,0,0,NULL},
-  {"",0,NULL,0,0,0,NULL},
   {"Adjust brush pick:",1,&(selected_config.Adjust_brush_pick),0,1,0,Lookup_YesNo},
   {"Undo pages:",1,&(selected_config.Max_undo_pages),1,99,5,NULL},
   {"Vertices per polygon:",4,&(selected_config.Nb_max_vertices_per_polygon),2,16384,5,NULL},
@@ -954,9 +962,9 @@ void Button_Settings(void)
   {"Auto count colors:",1,&(selected_config.Auto_nb_used),0,1,0,Lookup_YesNo},
   {"Right click colorpick:",1,&(selected_config.Right_click_colorpick),0,1,0,Lookup_YesNo},
   {"",0,NULL,0,0,0,NULL},
+  {"",0,NULL,0,0,0,NULL},
   
   {"      --- File selector  ---",0,NULL,0,0,0,NULL},
-  {"",0,NULL,0,0,0,NULL},
   {"Show in fileselector",0,NULL,0,0,0,NULL},
   {"  Hidden files:",4,&(selected_config.Show_hidden_files),0,1,0,Lookup_YesNo},
   {"  Hidden dirs:",4,&(selected_config.Show_hidden_directories),0,1,0,Lookup_YesNo},
@@ -966,9 +974,9 @@ void Button_Settings(void)
   {"Auto set resolution:",1,&(selected_config.Auto_set_res), 0,1,0,Lookup_YesNo},
   {"  According to:",1,&(selected_config.Set_resolution_according_to), 1,2,0,Lookup_AutoRes},
   {"Backup:",1,&(selected_config.Backup), 0,1,0,Lookup_YesNo},
+  {"",0,NULL,0,0,0,NULL},
   
   {"      --- Format options  ---",0,NULL,0,0,0,NULL},
-  {"",0,NULL,0,0,0,NULL},
   {"Screen size in GIF:",1,&(selected_config.Screen_size_in_GIF),0,1,0,Lookup_YesNo},
   {"Clear palette:",1,&(selected_config.Clear_palette),0,1,0,Lookup_YesNo},
   {"",0,NULL,0,0,0,NULL},
@@ -978,6 +986,7 @@ void Button_Settings(void)
   {"",0,NULL,0,0,0,NULL},
   {"",0,NULL,0,0,0,NULL},
   {"",0,NULL,0,0,0,NULL},
+  {"",0,NULL,0,0,0,NULL},
   
 
   };
diff --git a/src/helpfile.h b/src/helpfile.h
index 11d246a8..7632c039 100644
--- a/src/helpfile.h
+++ b/src/helpfile.h
@@ -2389,6 +2389,14 @@ static const T_Help_table helptable_settings_details[] =
   HELP_TEXT ("GrafX2 to recognize them as a combo.")
   HELP_TEXT ("")
   HELP_TEXT ("")
+  HELP_BOLD ("  Swap buttons")
+  HELP_TEXT ("This setting determines which key inverts")
+  HELP_TEXT ("the mouse buttons when it's held : A left")
+  HELP_TEXT ("click is then interpreted as a right-click.")
+  HELP_TEXT ("It's especially useful for one-button")
+  HELP_TEXT ("controllers, such as touchscreens and")
+  HELP_TEXT ("tablets.")
+  HELP_TEXT ("")
   HELP_TITLE("EDITING")
   HELP_TEXT ("")
   HELP_TEXT ("")
@@ -2432,7 +2440,7 @@ static const T_Help_table helptable_settings_details[] =
   HELP_TEXT ("This mode prevents you from painting with")  
   HELP_TEXT ("Background color.")
   HELP_TEXT ("This option is ignored when the Shade,")
-  HELP_TEXT ("Quick-shade, or Tiling mode is used.")  
+  HELP_TEXT ("Quick-shade, or Tiling mode is used.")    
 };
 
 static const T_Help_table helptable_clear[] =
diff --git a/src/input.c b/src/input.c
index 38f91172..a6e33433 100644
--- a/src/input.c
+++ b/src/input.c
@@ -83,6 +83,7 @@ int  Mouse_moved; ///< Boolean, Set to true if any cursor movement occurs.
 word Input_new_mouse_X;
 word Input_new_mouse_Y;
 byte Input_new_mouse_K;
+byte Button_inverter=0; // State of the key that swaps mouse buttons.
 
 byte Mouse_mode = 0; ///< Mouse mode = 0:normal, 1:emulated with custom sensitivity.
 short Mouse_virtual_x_position;
@@ -338,11 +339,19 @@ int Handle_mouse_click(SDL_MouseButtonEvent event)
     switch(event.button)
     {
         case SDL_BUTTON_LEFT:
-            Input_new_mouse_K |= 1;
+            if (Button_inverter)
+              Input_new_mouse_K |= 2;
+            else
+              Input_new_mouse_K |= 1;
+            break;
             break;
 
         case SDL_BUTTON_RIGHT:
-            Input_new_mouse_K |= 2;
+            if (Button_inverter)
+              Input_new_mouse_K |= 1;
+            else
+              Input_new_mouse_K |= 2;
+            break;
             break;
 
         case SDL_BUTTON_MIDDLE:
@@ -368,11 +377,17 @@ int Handle_mouse_release(SDL_MouseButtonEvent event)
     switch(event.button)
     {
         case SDL_BUTTON_LEFT:
-            Input_new_mouse_K &= ~1;
+            if (Button_inverter)
+              Input_new_mouse_K &= ~2;
+            else
+              Input_new_mouse_K &= ~1;
             break;
 
         case SDL_BUTTON_RIGHT:
-            Input_new_mouse_K &= ~2;
+            if (Button_inverter)
+              Input_new_mouse_K &= ~1;
+            else
+              Input_new_mouse_K &= ~2;
             break;
     }
     
@@ -384,8 +399,45 @@ int Handle_mouse_release(SDL_MouseButtonEvent event)
 int Handle_key_press(SDL_KeyboardEvent event)
 {
     //Appui sur une touche du clavier
+    int modifier;
+  
     Key = Keysym_to_keycode(event.keysym);
     Key_ANSI = Keysym_to_ANSI(event.keysym);
+    switch(event.keysym.sym)
+    {
+      case SDLK_RSHIFT:
+      case SDLK_LSHIFT:
+        modifier=MOD_SHIFT;
+        break;
+
+      case SDLK_RCTRL:
+      case SDLK_LCTRL:
+        modifier=MOD_CTRL;
+        break;
+
+      case SDLK_RALT:
+      case SDLK_LALT:
+      case SDLK_MODE:
+        modifier=MOD_ALT;
+        break;
+
+      case SDLK_RMETA:
+      case SDLK_LMETA:
+        modifier=MOD_META;
+        break;
+
+      default:
+        modifier=0;
+    }
+    if (Config.Swap_buttons && modifier == Config.Swap_buttons && Button_inverter==0)
+    {
+      Button_inverter=1;
+      if (Input_new_mouse_K)
+      {
+        Input_new_mouse_K ^= 3; // Flip bits 0 and 1
+        return Move_cursor_with_constraints();
+      }
+    }
 
     if(Is_shortcut(Key,SPECIAL_MOUSE_UP))
     {
@@ -433,6 +485,15 @@ int Release_control(int key_code, int modifier)
       Snap_axis = 0;
       need_feedback = 1;
     }
+    if (Config.Swap_buttons && modifier == Config.Swap_buttons && Button_inverter==1)
+    {
+      Button_inverter=0;
+      if (Input_new_mouse_K)
+      {      
+        Input_new_mouse_K ^= 3; // Flip bits 0 and 1
+        return Move_cursor_with_constraints();
+      }
+    }
 
     if((key_code && key_code == (Config_Key[SPECIAL_MOUSE_UP][0]&0x0FFF)) || (Config_Key[SPECIAL_MOUSE_UP][0]&modifier) ||
       (key_code && key_code == (Config_Key[SPECIAL_MOUSE_UP][1]&0x0FFF)) || (Config_Key[SPECIAL_MOUSE_UP][1]&modifier))
@@ -538,12 +599,12 @@ int Handle_joystick_press(SDL_JoyButtonEvent event)
     }
     if (event.button == Joybutton_left_click)
     {
-      Input_new_mouse_K=1;
+      Input_new_mouse_K = Button_inverter ? 2 : 1;
       return Move_cursor_with_constraints();
     }
     if (event.button == Joybutton_right_click)
     {
-      Input_new_mouse_K=2;
+      Input_new_mouse_K = Button_inverter ? 1 : 2;
       return Move_cursor_with_constraints();
     }
     switch(event.button)
@@ -768,6 +829,7 @@ int Get_input(int sleep_time)
     Mouse_moved=0;
     Input_new_mouse_X = Mouse_X;
     Input_new_mouse_Y = Mouse_Y;
+    Input_new_mouse_K = Mouse_K;
 
     // Not using SDL_PollEvent() because every call polls the input
     // device. In some cases such as high-sensitivity mouse or cheap
diff --git a/src/readini.c b/src/readini.c
index 6d1997df..c280574d 100644
--- a/src/readini.c
+++ b/src/readini.c
@@ -916,6 +916,29 @@ int Load_INI(T_Config * conf)
     conf->Sync_views=(values[0]!=0);
   }
   
+  conf->Swap_buttons=0;
+  // Optional, key for swap buttons (>=2.3)
+  if (!Load_INI_get_values (file,buffer,"Swap_buttons",1,values))
+  {
+    switch(values[0])
+    {
+      case 1:
+        conf->Swap_buttons=MOD_SHIFT;
+        break;
+      case 2:
+        conf->Swap_buttons=MOD_CTRL;
+        break;
+      case 3:
+        conf->Swap_buttons=MOD_ALT;
+        break;
+      case 4:
+        conf->Swap_buttons=MOD_META;
+        break;
+    }
+  }
+  
+  
+  
   // Insert new values here
 
   fclose(file);
diff --git a/src/saveini.c b/src/saveini.c
index a3d9eb54..1d1ae41d 100644
--- a/src/saveini.c
+++ b/src/saveini.c
@@ -393,8 +393,8 @@ void Save_INI_flush(FILE * old_file,FILE * new_file,char * buffer)
 
 int Save_INI(T_Config * conf)
 {
-  FILE * Ancien_fichier;
-  FILE * Nouveau_fichier;
+  FILE * old_file;
+  FILE * new_file;
   char * buffer;
   int    values[3];
   char   filename[MAX_PATH_CHARACTERS];
@@ -426,236 +426,236 @@ int Save_INI(T_Config * conf)
   // On récupère un fichier INI "propre" à partir de gfx2def.ini
   strcpy(ref_ini_file,Data_directory);
   strcat(ref_ini_file,"gfx2def.ini");
-  Ancien_fichier=fopen(ref_ini_file,"rb");
-  if (Ancien_fichier==0)
+  old_file=fopen(ref_ini_file,"rb");
+  if (old_file==0)
   {
-    fclose(Ancien_fichier);
+    fclose(old_file);
     free(buffer);
     return ERROR_INI_MISSING;
   }
-  Nouveau_fichier=fopen(filename,"wb");
-  if (Nouveau_fichier==0)
+  new_file=fopen(filename,"wb");
+  if (new_file==0)
   {
     free(buffer);
     return ERROR_SAVING_INI;
   }
-  if ((return_code=Save_INI_reach_group(Ancien_fichier,Nouveau_fichier,buffer,"[MOUSE]")))
+  if ((return_code=Save_INI_reach_group(old_file,new_file,buffer,"[MOUSE]")))
     goto Erreur_Retour;
 
   values[0]=conf->Mouse_sensitivity_index_x;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"X_sensitivity",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"X_sensitivity",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Mouse_sensitivity_index_y;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Y_sensitivity",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Y_sensitivity",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=0;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"X_correction_factor",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"X_correction_factor",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=0;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Y_correction_factor",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Y_correction_factor",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Cursor)+1;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Cursor_aspect",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Cursor_aspect",1,values,0)))
     goto Erreur_Retour;
 
-  if ((return_code=Save_INI_reach_group(Ancien_fichier,Nouveau_fichier,buffer,"[MENU]")))
+  if ((return_code=Save_INI_reach_group(old_file,new_file,buffer,"[MENU]")))
     goto Erreur_Retour;
 
   values[0]=conf->Fav_menu_colors[2].R>>2;
   values[1]=conf->Fav_menu_colors[2].G>>2;
   values[2]=conf->Fav_menu_colors[2].B>>2;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Light_color",3,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Light_color",3,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Fav_menu_colors[1].R>>2;
   values[1]=conf->Fav_menu_colors[1].G>>2;
   values[2]=conf->Fav_menu_colors[1].B>>2;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Dark_color",3,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Dark_color",3,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Ratio;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Menu_ratio",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Menu_ratio",1,values,0)))
     goto Erreur_Retour;
 
-  if ((return_code=Save_INI_reach_group(Ancien_fichier,Nouveau_fichier,buffer,"[FILE_SELECTOR]")))
+  if ((return_code=Save_INI_reach_group(old_file,new_file,buffer,"[FILE_SELECTOR]")))
     goto Erreur_Retour;
 
   values[0]=conf->Show_hidden_files?1:0;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Show_hidden_files",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Show_hidden_files",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Show_hidden_directories?1:0;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Show_hidden_directories",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Show_hidden_directories",1,values,1)))
     goto Erreur_Retour;
 
 /*  values[0]=conf->Show_system_directories?1:0;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Show_system_directories",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Show_system_directories",1,values,1)))
     goto Erreur_Retour;
 */
   values[0]=conf->Timer_delay;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Preview_delay",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Preview_delay",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Maximize_preview;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Maximize_preview",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Maximize_preview",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Find_file_fast;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Find_file_fast",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Find_file_fast",1,values,0)))
     goto Erreur_Retour;
 
 
-  if ((return_code=Save_INI_reach_group(Ancien_fichier,Nouveau_fichier,buffer,"[LOADING]")))
+  if ((return_code=Save_INI_reach_group(old_file,new_file,buffer,"[LOADING]")))
     goto Erreur_Retour;
 
   values[0]=conf->Auto_set_res;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Auto_set_resolution",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Auto_set_resolution",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Set_resolution_according_to;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Set_resolution_according_to",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Set_resolution_according_to",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Clear_palette;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Clear_palette",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Clear_palette",1,values,1)))
     goto Erreur_Retour;
 
 
-  if ((return_code=Save_INI_reach_group(Ancien_fichier,Nouveau_fichier,buffer,"[MISCELLANEOUS]")))
+  if ((return_code=Save_INI_reach_group(old_file,new_file,buffer,"[MISCELLANEOUS]")))
     goto Erreur_Retour;
 
   values[0]=conf->Display_image_limits;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Draw_limits",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Draw_limits",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Adjust_brush_pick;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Adjust_brush_pick",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Adjust_brush_pick",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=2-conf->Coords_rel;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Coordinates",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Coordinates",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Backup;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Backup",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Backup",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Max_undo_pages;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Undo_pages",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Undo_pages",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Delay_left_click_on_slider;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Gauges_scrolling_speed_Left",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Gauges_scrolling_speed_Left",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Delay_right_click_on_slider;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Gauges_scrolling_speed_Right",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Gauges_scrolling_speed_Right",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Auto_save;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Auto_save",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Auto_save",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Nb_max_vertices_per_polygon;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Vertices_per_polygon",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Vertices_per_polygon",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=conf->Fast_zoom;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Fast_zoom",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Fast_zoom",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Separate_colors;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Separate_colors",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Separate_colors",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->FX_Feedback;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"FX_feedback",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"FX_feedback",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Safety_colors;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Safety_colors",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Safety_colors",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Opening_message;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Opening_message",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Opening_message",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Clear_with_stencil;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Clear_with_stencil",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Clear_with_stencil",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Auto_discontinuous;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Auto_discontinuous",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Auto_discontinuous",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Screen_size_in_GIF;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Save_screen_size_in_GIF",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Save_screen_size_in_GIF",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Auto_nb_used;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Auto_nb_colors_used",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Auto_nb_colors_used",1,values,1)))
     goto Erreur_Retour;
 
-  if ((return_code=Save_INI_set_strings (Ancien_fichier,Nouveau_fichier,buffer,"Default_video_mode",Mode_label(conf->Default_resolution))))
+  if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Default_video_mode",Mode_label(conf->Default_resolution))))
     goto Erreur_Retour;
 
   values[0]=Video_mode[0].Width;
   values[1]=Video_mode[0].Height;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Default_window_size",2,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Default_window_size",2,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Mouse_merge_movement);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Merge_movement",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Merge_movement",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Palette_cells_X);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Palette_cells_X",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Palette_cells_X",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Palette_cells_Y);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Palette_cells_Y",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Palette_cells_Y",1,values,0)))
     goto Erreur_Retour;
 
   for (index=0;index<NB_BOOKMARKS;index++)
   {
-    if ((return_code=Save_INI_set_strings (Ancien_fichier,Nouveau_fichier,buffer,"Bookmark_label",conf->Bookmark_label[index])))
+    if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Bookmark_label",conf->Bookmark_label[index])))
       goto Erreur_Retour;
-    if ((return_code=Save_INI_set_strings (Ancien_fichier,Nouveau_fichier,buffer,"Bookmark_directory",conf->Bookmark_directory[index])))
+    if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Bookmark_directory",conf->Bookmark_directory[index])))
       goto Erreur_Retour;
   }
   values[0]=(conf->Palette_vertical);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Palette_vertical",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Palette_vertical",1,values,1)))
     goto Erreur_Retour;
 
   values[0]=conf->Window_pos_x;
   values[1]=conf->Window_pos_y;
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Window_position",2,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Window_position",2,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Double_click_speed);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Double_click_speed",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Double_click_speed",1,values,0)))
     goto Erreur_Retour;
     
   values[0]=(conf->Double_key_speed);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Double_key_speed",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Double_key_speed",1,values,0)))
     goto Erreur_Retour;
 
-  if ((return_code=Save_INI_set_strings (Ancien_fichier,Nouveau_fichier,buffer,"Skin_file",conf->Skin_file)))
+  if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Skin_file",conf->Skin_file)))
     goto Erreur_Retour;
     
-  if ((return_code=Save_INI_set_strings (Ancien_fichier,Nouveau_fichier,buffer,"Font_file",conf->Font_file)))
+  if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Font_file",conf->Font_file)))
     goto Erreur_Retour;
 
   values[0]=(conf->Grid_XOR_color);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Grid_XOR_color",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Grid_XOR_color",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=(Pixel_ratio);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Pixel_ratio",1,values,0))) {
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Pixel_ratio",1,values,0))) {
     DEBUG("saving pixel ratio",return_code);
     goto Erreur_Retour;
   }
@@ -670,23 +670,43 @@ int Save_INI(T_Config * conf)
   for (; index<8;index++)
     values[0] |= (1<<index);
     
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Menubars_visible",1,values,0)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Menubars_visible",1,values,0)))
     goto Erreur_Retour;
 
   values[0]=(conf->Right_click_colorpick);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Right_click_colorpick",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Right_click_colorpick",1,values,1)))
     goto Erreur_Retour;
     
   values[0]=(conf->Sync_views);
-  if ((return_code=Save_INI_set_values (Ancien_fichier,Nouveau_fichier,buffer,"Sync_views",1,values,1)))
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Sync_views",1,values,1)))
+    goto Erreur_Retour;
+    
+  switch(conf->Swap_buttons)
+  {
+      case MOD_SHIFT:
+        values[0]=1;
+        break;
+      case MOD_CTRL:
+        values[0]=2;
+        break;
+      case MOD_ALT:
+        values[0]=3;
+        break;
+      case MOD_META:
+        values[0]=4;
+        break;
+      default:
+        values[0]=0;
+  }
+  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Swap_buttons",1,values,0)))
     goto Erreur_Retour;
   
   // Insert new values here
   
-  Save_INI_flush(Ancien_fichier,Nouveau_fichier,buffer);
+  Save_INI_flush(old_file,new_file,buffer);
 
-  fclose(Nouveau_fichier);
-  fclose(Ancien_fichier);
+  fclose(new_file);
+  fclose(old_file);
 
   // On efface le fichier temporaire <=> Ancienne version du .INI
   if (ini_file_exists)
@@ -698,8 +718,8 @@ int Save_INI(T_Config * conf)
 
   Erreur_Retour:
 
-    fclose(Nouveau_fichier);
-    fclose(Ancien_fichier);
+    fclose(new_file);
+    fclose(old_file);
     free(buffer);
     return return_code;
 
diff --git a/src/struct.h b/src/struct.h
index 7b178841..b8221f7e 100644
--- a/src/struct.h
+++ b/src/struct.h
@@ -358,6 +358,7 @@ typedef struct
   byte Right_click_colorpick;            ///< Boolean, true to enable a "tablet" mode, where RMB acts as instant colorpicker
   byte Sync_views;                       ///< Boolean, true when the Main and Spare should share their viewport settings.
   byte Stylus_mode;                      ///< Boolean, true to tweak some tools (eg:Curve) for single-button stylus.
+  word Swap_buttons;                     ///< Sets which key swaps mouse buttons : 0=none, or MOD_SHIFT, MOD_CTRL, MOD_ALT, MOD_META.
 } T_Config;
 
 // Structures utilisées pour les descriptions de pages et de liste de pages.