diff --git a/scconfig/src/gui/find_lesstif2.c b/scconfig/src/gui/find_lesstif2.c
index dfbc227e..af98442d 100644
--- a/scconfig/src/gui/find_lesstif2.c
+++ b/scconfig/src/gui/find_lesstif2.c
@@ -1,6 +1,6 @@
 /*
     scconfig - gui lib detection - lesstif
-    Copyright (C) 2015  Tibor Palinkas
+    Copyright (C) 2015,2021  Tibor Palinkas
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
@@ -67,3 +67,36 @@ int find_lesstif2(const char *name, int logdepth, int fatal, const char *call, c
 	return try_fail(logdepth, node);
 
 }
+
+int find_lesstif2_exthi(const char *name, int logdepth, int fatal, const char *call, const char *arg)
+{
+	const char *test_c =
+		NL "#include <Xm/MainW.h>"
+		NL "int main(int argc, char *argv[])"
+		NL "{"
+		NL "	return XmEXTERNAL_HIGHLIGHT;"
+		NL "}"
+		NL;
+
+	const char *node = "libs/gui/lesstif2/exthi";
+//	char **cflags,  *cflags_arr[]  = {"", "-I/opt/X11/include", NULL};
+//	char **ldflags, *ldflags_arr[] = {"-lXm -lX11", "-lXm -lXt", "-L/opt/X11/lib -lXm -lXt  -lX11", NULL}; /* note: -lXt must be after -lXm else lesstif fails to init with runtime error */
+	const char *cflags, *ldflags;
+	(void) call;  /* not used */
+	(void) arg;  /* not used */
+
+	if (require("cc/cc", logdepth, fatal) || require("libs/gui/lesstif2", logdepth, fatal))
+		return 1;
+
+	report("Checking for lesstif2 XmEXTERNAL_HIGHLIGHT... ");
+	logprintf(logdepth, "find_lesstif_exthi:\n");
+	logdepth++;
+
+	cflags = get("libs/gui/lesstif2/cflags");
+	ldflags = get("libs/gui/lesstif2/ldflags");
+
+	if (try_icl_norun(logdepth, node, test_c, NULL, cflags, ldflags) != 0)
+		return 0;
+
+	return try_fail(logdepth, node);
+}
diff --git a/scconfig/src/gui/find_lesstif2.h b/scconfig/src/gui/find_lesstif2.h
index 88f8db1f..cfcec99c 100644
--- a/scconfig/src/gui/find_lesstif2.h
+++ b/scconfig/src/gui/find_lesstif2.h
@@ -1,2 +1,2 @@
 int find_lesstif2(const char *name, int logdepth, int fatal);
-
+int find_lesstif2_exthi(const char *name, int logdepth, int fatal, const char *call, const char *arg);
diff --git a/scconfig/src/gui/gui.c b/scconfig/src/gui/gui.c
index 565d0010..385cb175 100644
--- a/scconfig/src/gui/gui.c
+++ b/scconfig/src/gui/gui.c
@@ -26,6 +26,7 @@ void deps_gui_init()
 	dep_add("libs/gui/gtk2/key_prefix",     find_gtk2_key_prefix);
 	dep_add("libs/gui/gtk2/modversion",     find_gtk2_modversion);
 	dep_add("libs/gui/gtk3/*",              find_gtk3);
+	dep_add("libs/gui/lesstif2/exthi/*",    find_lesstif2_exthi);
 	dep_add("libs/gui/lesstif2/*",          find_lesstif2);
 	dep_add("libs/gui/libstroke/*",         find_libstroke);
 	dep_add("libs/gui/gd/gdImagePng/*",     find_gdimagepng);
diff --git a/src/actions.c b/src/actions.c
index 859b6513..6a6ba6ac 100644
--- a/src/actions.c
+++ b/src/actions.c
@@ -112,7 +112,7 @@ void set_snap(double newsnap) /*  20161212 set new snap factor and just notify n
     static double default_snap = -1.0;
 
     if(default_snap == -1.0) {
-      default_snap = atof(tclgetvar("snap"));
+      default_snap = atof(tclgetvar("cadsnap"));
       if(default_snap==0.0) default_snap = CADSNAP;
     }
     cadsnap = newsnap ? newsnap : default_snap;
@@ -122,7 +122,7 @@ void set_snap(double newsnap) /*  20161212 set new snap factor and just notify n
     } else {
       tcleval(".statusbar.3 configure -background OrangeRed");
     }
-    tclsetvar("snap", str);
+    tclsetvar("cadsnap", str);
 }
 
 void set_grid(double newgrid)
@@ -131,7 +131,7 @@ void set_grid(double newgrid)
     static double default_grid = -1.0;
 
     if(default_grid == -1.0) {
-      default_grid = atof(tclgetvar("grid"));
+      default_grid = atof(tclgetvar("cadgrid"));
       if(default_grid==0.0) default_grid = CADGRID;
     }
     cadgrid = newgrid ? newgrid : default_grid;
@@ -142,7 +142,7 @@ void set_grid(double newgrid)
     } else {
       tcleval(".statusbar.5 configure -background OrangeRed");
     }
-    tclsetvar("grid", str);
+    tclsetvar("cadgrid", str);
 }
 
 int set_netlist_dir(int force, char *dir)
@@ -246,7 +246,7 @@ void toggle_fullscreen()
   } else {
     window_state(display , parent_of_topwindow,normal);
   }
-  pending_fullzoom=1;
+  xctx->pending_fullzoom=1;
 }
 
 #ifdef __unix__
@@ -578,15 +578,15 @@ void enable_layers(void)
 {
   int i;
   char tmp[50];
-  n_active_layers = 0;
+  xctx->n_active_layers = 0;
   for(i = 0; i< cadlayers; i++) {
     my_snprintf(tmp, S(tmp), "enable_layer(%d)",i);
     if(tclgetvar(tmp)[0] == '0') enable_layer[i] = 0;
     else {
       enable_layer[i] = 1;
       if(i>=7) {
-        active_layer[n_active_layers] = i;
-        n_active_layers++;
+        xctx->active_layer[xctx->n_active_layers] = i;
+        xctx->n_active_layers++;
       }
     }
   }
@@ -861,7 +861,7 @@ int place_symbol(int pos, const char *symbol_name, double x, double y, short rot
   dbg(1, "place_symbol() :all inst_ptr members set\n");  /*  03-02-2000 */
   if(first_call) hash_all_names(n);
   if(inst_props) {
-    new_prop_string(n, inst_props,!first_call, dis_uniq_names); /*  20171214 first_call */
+    new_prop_string(n, inst_props,!first_call, disable_unique_names); /*  20171214 first_call */
   }
   else {
     set_inst_prop(n); /* no props, get from sym template, also calls new_prop_string() */
@@ -1615,7 +1615,7 @@ void new_wire(int what, double mx_snap, double my_snap)
   if( (what & PLACE) ) {
     if( (xctx->ui_state & STARTWIRE) && (xctx->nl_x1!=xctx->nl_x2 || xctx->nl_y1!=xctx->nl_y2) ) {
       push_undo();
-      if(manhattan_lines==1) {
+      if(xctx->manhattan_lines==1) {
         if(xctx->nl_xx2!=xctx->nl_xx1) {
           xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
           xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1632,7 +1632,7 @@ void new_wire(int what, double mx_snap, double my_snap)
           hash_wire(XINSERT, xctx->wires-1, 1);
           drawline(WIRELAYER,NOW, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2, 0);
         }
-      } else if(manhattan_lines==2) {
+      } else if(xctx->manhattan_lines==2) {
         if(xctx->nl_yy2!=xctx->nl_yy1) {
           xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
           xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1683,7 +1683,7 @@ void new_wire(int what, double mx_snap, double my_snap)
       xctx->nl_yy1=xctx->nl_y1;
       xctx->nl_xx2=xctx->mousex_snap;
       xctx->nl_yy2=xctx->mousey_snap;
-      if(manhattan_lines==1) {
+      if(xctx->manhattan_lines==1) {
         xctx->nl_x2 = mx_snap; xctx->nl_y2 = my_snap;
         xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
         xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1693,7 +1693,7 @@ void new_wire(int what, double mx_snap, double my_snap)
         xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
         ORDER(xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
         drawtempline(gc[WIRELAYER], NOW, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
-      } else if(manhattan_lines==2) {
+      } else if(xctx->manhattan_lines==2) {
         xctx->nl_x2 = mx_snap; xctx->nl_y2 = my_snap;
         xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
         xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1717,7 +1717,7 @@ void new_wire(int what, double mx_snap, double my_snap)
     xctx->ui_state &= ~STARTWIRE;
   }
   if( (what & RUBBER)  ) {
-    if(manhattan_lines==1) {
+    if(xctx->manhattan_lines==1) {
       xctx->nl_xx1=xctx->nl_x1;xctx->nl_yy1=xctx->nl_y1;
       xctx->nl_xx2=xctx->nl_x2;xctx->nl_yy2=xctx->nl_y2;
       ORDER(xctx->nl_xx1,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy1);
@@ -1738,7 +1738,7 @@ void new_wire(int what, double mx_snap, double my_snap)
         ORDER(xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
         drawtempline(gc[WIRELAYER], NOW, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
       }
-    } else if(manhattan_lines==2) {
+    } else if(xctx->manhattan_lines==2) {
       xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
       xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
       ORDER(xctx->nl_xx1,xctx->nl_yy1,xctx->nl_xx1,xctx->nl_yy2);
@@ -1878,7 +1878,7 @@ void new_line(int what)
     if( (xctx->nl_x1!=xctx->nl_x2 || xctx->nl_y1!=xctx->nl_y2) && (xctx->ui_state & STARTLINE) )
     {
       push_undo();
-      if(manhattan_lines==1) {
+      if(xctx->manhattan_lines==1) {
         if(xctx->nl_xx2!=xctx->nl_xx1) {
           xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
           xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1893,7 +1893,7 @@ void new_line(int what)
           storeobject(-1, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2,LINE,xctx->rectcolor,0,NULL);
           drawline(xctx->rectcolor,NOW, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2, 0);
         }
-      } else if(manhattan_lines==2) {
+      } else if(xctx->manhattan_lines==2) {
         if(xctx->nl_yy2!=xctx->nl_yy1) {
           xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
           xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
@@ -1926,7 +1926,7 @@ void new_line(int what)
 
   if(what & RUBBER)
   {
-    if(manhattan_lines==1) {
+    if(xctx->manhattan_lines==1) {
       xctx->nl_xx1=xctx->nl_x1;xctx->nl_yy1=xctx->nl_y1;
       xctx->nl_xx2=xctx->nl_x2;xctx->nl_yy2=xctx->nl_y2;
       ORDER(xctx->nl_xx1,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy1);
@@ -1947,7 +1947,7 @@ void new_line(int what)
         ORDER(xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
         drawtempline(gc[xctx->rectcolor], NOW, xctx->nl_xx2,xctx->nl_yy1,xctx->nl_xx2,xctx->nl_yy2);
       }
-    } else if(manhattan_lines==2) {
+    } else if(xctx->manhattan_lines==2) {
       xctx->nl_xx1 = xctx->nl_x1; xctx->nl_yy1 = xctx->nl_y1;
       xctx->nl_xx2 = xctx->nl_x2; xctx->nl_yy2 = xctx->nl_y2;
       ORDER(xctx->nl_xx1,xctx->nl_yy1,xctx->nl_xx1,xctx->nl_yy2);
diff --git a/src/callback.c b/src/callback.c
index eceb18c3..8bae3e08 100644
--- a/src/callback.c
+++ b/src/callback.c
@@ -304,14 +304,14 @@ int callback(int event, int mx, int my, KeySym key,
    if(key==' ') {
      if(xctx->ui_state & STARTWIRE) { /*  & instead of == 20190409 */
        new_wire(RUBBER|CLEAR, xctx->mousex_snap, xctx->mousey_snap);
-       manhattan_lines++;
-       manhattan_lines %=3;
+       xctx->manhattan_lines++;
+       xctx->manhattan_lines %=3;
        new_wire(RUBBER, xctx->mousex_snap, xctx->mousey_snap);
 
      } else if(xctx->ui_state==STARTLINE) {
        new_line(RUBBER|CLEAR);
-       manhattan_lines++;
-       manhattan_lines %=3;
+       xctx->manhattan_lines++;
+       xctx->manhattan_lines %=3;
        new_line(RUBBER);
      } else {
        if(xctx->semaphore<2) {
@@ -480,17 +480,17 @@ int callback(int event, int mx, int my, KeySym key,
    if(key == '='  && (state &ControlMask))              /* toggle fill rectangles */
    {
     int x;
-    fill++;
-    if(fill==3) fill=0;
+    xctx->fill_pattern++;
+    if(xctx->fill_pattern==3) xctx->fill_pattern=0;
 
-    if(fill==1) {
+    if(xctx->fill_pattern==1) {
      tcleval("alert_ { Stippled pattern fill} {}");
      for(x=0;x<cadlayers;x++) {
        if(fill_type[x]==1) XSetFillStyle(display,gcstipple[x],FillSolid);
        else XSetFillStyle(display,gcstipple[x],FillStippled);
      }
     }
-    else if(fill==2) {
+    else if(xctx->fill_pattern==2) {
      tcleval("alert_ { solid pattern fill} {}");
      for(x=0;x<cadlayers;x++)
       XSetFillStyle(display,gcstipple[x],FillSolid);
@@ -568,7 +568,7 @@ int callback(int event, int mx, int my, KeySym key,
     tcleval("set constrained_move 0" );
     constrained_move=0;
     xctx->last_command=0;
-    manhattan_lines = 0;
+    xctx->manhattan_lines = 0;
     dbg(1, "callback(): Escape: ui_state=%ld\n", xctx->ui_state);
     if(xctx->ui_state & STARTMOVE)
     {
@@ -646,7 +646,7 @@ int callback(int event, int mx, int my, KeySym key,
     char n[30];
     xctx->rectcolor = key - '0'+4;
     my_snprintf(n, S(n), "%d", xctx->rectcolor);
-    Tcl_VarEval(interp, "xschem set xctx->rectcolor ", n, "; reconfigure_layers_button", NULL);
+    Tcl_VarEval(interp, "xschem set rectcolor ", n, NULL);
     dbg(1, "callback(): new color: %d\n",color_index[xctx->rectcolor]);
     break;
    }
@@ -958,7 +958,7 @@ int callback(int event, int mx, int my, KeySym key,
                                                         /* with 'propag=' prop set on pins */
    {
     if(xctx->semaphore >= 2) break;
-    enable_drill=1;
+    xctx->enable_drill=1;
     hilight_net(0);
     redraw_hilights(0);
     /* draw_hilight_net(1); */
@@ -967,7 +967,7 @@ int callback(int event, int mx, int my, KeySym key,
    if(key=='k' && state==0)                             /* hilight net */
    {
     if(xctx->semaphore >= 2) break;
-    enable_drill=0;
+    xctx->enable_drill=0;
     hilight_net(0);
     redraw_hilights(0);
     /* draw_hilight_net(1); */
@@ -978,7 +978,7 @@ int callback(int event, int mx, int my, KeySym key,
     xRect boundbox;
     int big =  xctx->wires> 2000 || xctx->instances > 2000 ;
     if(xctx->semaphore >= 2) break;
-    enable_drill=0;
+    xctx->enable_drill=0;
     if(!big) calc_drawing_bbox(&boundbox, 2);
     clear_all_hilights();
     /* undraw_hilight_net(1); */
@@ -1000,7 +1000,7 @@ int callback(int event, int mx, int my, KeySym key,
      if(xctx->semaphore >= 2) break;
      tcleval("info exists sim");
      if(tclresult()[0] == '1') exists = 1;
-     enable_drill = 0;
+     xctx->enable_drill = 0;
      if(exists) {
        tool = atol(tclgetvar("sim(spicewave,default)"));
        my_snprintf(str, S(str), "sim(spicewave,%d,name)", tool);
diff --git a/src/draw.c b/src/draw.c
index f28ae008..4b2872d8 100644
--- a/src/draw.c
+++ b/src/draw.c
@@ -1130,7 +1130,7 @@ void drawarc(int c, int what, double x, double y, double r, double a, double b,
      XDrawArc(display, xctx->save_pixmap, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
    }
 
-   if(fill && fill_type[c]){
+   if(xctx->fill_pattern && fill_type[c]){
      if(arc_fill) {
        if(draw_window)
          XFillArc(display, xctx->window, gcstipple[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
@@ -1160,7 +1160,7 @@ void filledrect(int c, int what, double rectx1,double recty1,double rectx2,doubl
  double x1,y1,x2,y2;
 
  if(!has_x) return;
- if(!fill || !fill_type[c]) return;
+ if(!xctx->fill_pattern || !fill_type[c]) return;
  if(what & NOW)
  {
   x1=X_TO_SCREEN(rectx1);
@@ -1314,7 +1314,7 @@ void drawpolygon(int c, int what, double *x, double *y, int points, int poly_fil
   if(draw_window) XDrawLines(display, xctx->window, gc[c], p, points, CoordModeOrigin);
   if(draw_pixmap)
     XDrawLines(display, xctx->save_pixmap, gc[c], p, points, CoordModeOrigin);
-  if(fill && fill_type[c]){
+  if(xctx->fill_pattern && fill_type[c]){
     if(poly_fill && (x[0] == x[points-1]) && (y[0] == y[points-1])) {
       if(draw_window) XFillPolygon(display, xctx->window, gcstipple[c], p, points, Polygontype, CoordModeOrigin);
       if(draw_pixmap)
diff --git a/src/editprop.c b/src/editprop.c
index 43d9a609..89b7be8b 100644
--- a/src/editprop.c
+++ b/src/editprop.c
@@ -388,7 +388,7 @@ void set_inst_prop(int i)
   my_strdup2(70, &xctx->inst[i].instname, get_tok_value(ptr, "name",0));
   if(xctx->inst[i].instname[0]) {
     my_strdup(101, &tmp, xctx->inst[i].prop_ptr);
-    new_prop_string(i, tmp, 0, dis_uniq_names);
+    new_prop_string(i, tmp, 0, disable_unique_names);
     my_free(724, &tmp);
   }
 }
@@ -1031,7 +1031,7 @@ void update_symbol(const char *result, int x)
                      /* set name of current inst */
       if(!pushed) { push_undo(); pushed=1;}
       if(!k) hash_all_names(i);
-      new_prop_string(i, ptr, k, dis_uniq_names); /* set new prop_ptr */
+      new_prop_string(i, ptr, k, disable_unique_names); /* set new prop_ptr */
     }
     my_strdup2(90, &xctx->inst[i].instname, get_tok_value(xctx->inst[i].prop_ptr, "name",0));
 
diff --git a/src/globals.c b/src/globals.c
index 8f35ef31..99ee3a02 100644
--- a/src/globals.c
+++ b/src/globals.c
@@ -131,9 +131,9 @@ double cadsnap = CADSNAP;
 int draw_grid=1;
 int big_grid_points=0;
 int rainbow_colors=0;
-int dis_uniq_names=0; /* if set allow instances with duplicate names */
+int disable_unique_names=0; /* if set allow instances with duplicate names */
 int persistent_command=0; /* remember last command 20181022 */
-int autotrim_wires=0;
+int autotrim_wires = 0;
 int color_ps=-1;
 int transparent_svg=-1;
 int only_probes=0;
@@ -164,7 +164,6 @@ int en_hilight_conn_inst = 0;
 int help=0; /* help option set to global scope, printing help is deferred */
             /* when configuration ~/.schem has been read 20140406 */
 int no_draw=0;
-int manhattan_lines=0;
 FILE *errfp;
 char *filename=NULL; /* filename given on cmdline */
 char user_conf_dir[PATH_MAX];
@@ -185,7 +184,6 @@ int debug_var=-10;  /* will be set to 0 in xinit.c */
 int tcp_port = 0;
 int do_print=0;
 int no_readline=0;
-int fill=1; /* filled rectangles */
 int draw_pixmap=1; /* use pixmap for double buffer */
 int draw_window=0;
 int text_svg=1; /* use <text> svg element for text instead of xschem's internal vector font */
@@ -197,9 +195,7 @@ int draw_dots=1;
 int draw_single_layer=-1;
 int yyparse_error = 0;
 int *enable_layer;
-int n_active_layers=0;
-int *active_layer;
-int depth;
+int screendepth;
 int *fill_type; /* for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
 char **color_array;
 char *xschem_executable=NULL;
@@ -209,13 +205,9 @@ int do_netlist=0;  /* set by process_options if user wants netllist from cmdline
 int do_simulation=0;
 int do_waves=0;
 int netlist_count=0; /* netlist counter incremented at any cell being netlisted */
-char hiersep[20]=".";
 char bus_char[3] = {0, 0, 0};
-int pending_fullzoom=0;
 int constrained_move = 0;
 double color_dim=0.0;
-int no_undo=0;
-int enable_drill=0; /* pass net hilights through components with 'propag=' property set on pins */
 int batch_mode = 0; /* no tcl console if set; batch mode */
 int show_erc=1;
 
diff --git a/src/hilight.c b/src/hilight.c
index e8ca84aa..1511b2ae 100644
--- a/src/hilight.c
+++ b/src/hilight.c
@@ -97,22 +97,22 @@ void free_hilight_hash(void) /* remove the whole hash table  */
 }
 
 /* by default: 
- * active_layer[0] = 7
- * active_layer[1] = 8
- * active_layer[2] = 10  if 9 is disabled it is skipped
+ * xctx->active_layer[0] = 7
+ * xctx->active_layer[1] = 8
+ * xctx->active_layer[2] = 10  if 9 is disabled it is skipped
  * ...
  * if a layer is disabled (not viewable) it is skipped
- * n_active_layers is the total number of layers for hilights.
- * standard xschem conf: cadlayers=22, n_active_layers=15 if no disabled layers.
+ * xctx->n_active_layers is the total number of layers for hilights.
+ * standard xschem conf: cadlayers=22, xctx->n_active_layers=15 if no disabled layers.
  */
 int get_color(int value)
 {
   int x;
 
   if(value < 0) return (-value) % cadlayers ;
-  if(n_active_layers) {
-    x = value%(n_active_layers);
-    return active_layer[x];
+  if(xctx->n_active_layers) {
+    x = value%(xctx->n_active_layers);
+    return xctx->active_layer[x];
   } else {
     return cadlayers > 5 ? 5 : cadlayers -1; /* desperate attempt to return a decent color */
   }
@@ -121,7 +121,7 @@ int get_color(int value)
 
 void incr_hilight_color(void)
 {
-  xctx->hilight_color = (xctx->hilight_color + 1) % (n_active_layers * cadlayers);
+  xctx->hilight_color = (xctx->hilight_color + 1) % (xctx->n_active_layers * cadlayers);
 }
 
 /* print all highlight signals which are not ports (in/out/inout). */
@@ -148,7 +148,7 @@ void create_plot_cmd(void)
   my_strncpy(rawfile, tclresult(), S(rawfile));
   tcleval("info exists sim");
   if(tclresult()[0] == '1') exists = 1;
-  enable_drill = 0;
+  xctx->enable_drill = 0;
   if(exists) {
     viewer = atol(tclgetvar("sim(spicewave,default)"));
     my_snprintf(tcl_str, S(tcl_str), "sim(spicewave,%d,name)", viewer);
@@ -296,14 +296,12 @@ struct hilight_hashentry *hilight_lookup(const char *token, int value, int what)
   struct hilight_hashentry *entry, *saveptr, **preventry;
   char *ptr;
   int s ;
-  int depth=0;
  
   if(token==NULL) return NULL;
   hashcode=hi_hash(token);
   index=hashcode % HASHSIZE;
   entry=xctx->hilight_table[index];
   preventry=&xctx->hilight_table[index];
-  depth=0;
   while(1) {
     if( !entry ) { /* empty slot */
       int lent = (strlen(token) + 8) & ~(size_t) 0x7; /* align to 8 byte boundaries */
@@ -341,7 +339,6 @@ struct hilight_hashentry *hilight_lookup(const char *token, int value, int what)
     }
     preventry=&entry->next; /* descend into the list. */
     entry = entry->next;
-    depth++;
   }
 }
 
@@ -1082,7 +1079,7 @@ void propagate_hilights(int set, int clear, int mode)
     }
   }
   xctx->hilight_nets = there_are_hilights();
-  if(xctx->hilight_nets && enable_drill && set) drill_hilight(mode);
+  if(xctx->hilight_nets && xctx->enable_drill && set) drill_hilight(mode);
 }
 
 /* use negative values to bypass the normal hilight color enumeration */
diff --git a/src/in_memory_undo.c b/src/in_memory_undo.c
index 9cf85cee..2e06e7ce 100644
--- a/src/in_memory_undo.c
+++ b/src/in_memory_undo.c
@@ -198,7 +198,7 @@ void push_undo(void)
 {
   int slot, i, c;
 
-  if(no_undo)return;
+  if(xctx->no_undo)return;
   if(!initialized) {
     initialized=1;
     init_undo();
@@ -316,7 +316,7 @@ void pop_undo(int redo)
 {
   int slot, i, c;
 
-  if(no_undo)return;
+  if(xctx->no_undo)return;
   if(redo) {
     if(xctx->cur_undo_ptr < xctx->head_undo_ptr) {
       xctx->cur_undo_ptr++;
diff --git a/src/move.c b/src/move.c
index d561e368..d14bb947 100644
--- a/src/move.c
+++ b/src/move.c
@@ -932,7 +932,7 @@ void copy_objects(int what)
         /* the newpropcnt argument is zero for the 1st call and used in  */
         /* new_prop_string() for cleaning some internal caches. */
         if(!newpropcnt) hash_all_names(xctx->instances);
-        new_prop_string(xctx->instances, xctx->inst[n].prop_ptr,newpropcnt++, dis_uniq_names);
+        new_prop_string(xctx->instances, xctx->inst[n].prop_ptr,newpropcnt++, disable_unique_names);
         my_strdup2(235, &xctx->inst[xctx->instances].instname,
                     get_tok_value(xctx->inst[xctx->instances].prop_ptr, "name", 0));
         xctx->instances++;
diff --git a/src/netlist.c b/src/netlist.c
index bdee1d61..98e409a3 100644
--- a/src/netlist.c
+++ b/src/netlist.c
@@ -407,7 +407,7 @@ void netlist_options(int i)
 
   str = get_tok_value(xctx->inst[i].prop_ptr, "hiersep", 0);
   if(str[0]) {
-    my_snprintf(hiersep, S(hiersep), "%s", str);
+    my_snprintf(xctx->hiersep, S(xctx->hiersep), "%s", str);
   }
 }
 
diff --git a/src/paste.c b/src/paste.c
index 5dadee61..f231b7a0 100644
--- a/src/paste.c
+++ b/src/paste.c
@@ -263,7 +263,7 @@ void merge_inst(int k,FILE *fd)
     ptr[i].node=NULL;
     load_ascii_string(&prop_ptr,fd);
     if(!k) hash_all_names(i);
-    new_prop_string(i, prop_ptr, k, dis_uniq_names);
+    new_prop_string(i, prop_ptr, k, disable_unique_names);
     /* the final tmp argument is zero for the 1st call and used in */
     /* new_prop_string() for cleaning some internal caches. */
     my_strdup2(306, &xctx->inst[i].instname, get_tok_value(xctx->inst[i].prop_ptr, "name", 0));
@@ -313,7 +313,7 @@ void merge_file(int selection_load, const char ext[])
     {
       my_snprintf(name, S(name), "%s/.clipboard.sch", user_conf_dir);
     }
-    if( (fd=fopen(name,"r"))!= NULL) {
+    if( (fd=fopen(name, fopen_read_mode))!= NULL) {
      xctx->prep_hi_structs=0;
      xctx->prep_net_structs=0;
      xctx->prep_hash_inst=0;
diff --git a/src/psprint.c b/src/psprint.c
index 7771e035..9a72aaf1 100644
--- a/src/psprint.c
+++ b/src/psprint.c
@@ -118,7 +118,7 @@ static void set_ps_colors(unsigned int pixel)
 
 static void ps_xdrawarc(int layer, int fillarc, double x, double y, double r, double a, double b)
 {
- if(fill && fillarc)
+ if(xctx->fill_pattern && fillarc)
    fprintf(fd, "%g %g %g %g %g A %g %g LT C F S\n", x, y, r, -a, -a-b, x, y);
  else
    fprintf(fd, "%g %g %g %g %g A S\n", x, y, r, -a, -a-b);
@@ -140,7 +140,7 @@ static void ps_xfillrectange(int layer, double x1, double y1, double x2,
                   double y2)
 {
  fprintf(fd, "%g %g %g %g R\n", x1,y1,x2-x1,y2-y1);
- if( (fill_type[layer] == 1) && fill) {
+ if( (fill_type[layer] == 1) && xctx->fill_pattern) {
    fprintf(fd, "%g %g %g %g RF\n", x1,y1,x2-x1,y2-y1);
    /* fprintf(fd,"fill\n"); */
  }
@@ -174,7 +174,7 @@ static void ps_drawpolygon(int c, int what, double *x, double *y, int points, in
     if(i==0) fprintf(fd, "NP\n%g %g MT\n", xx, yy);
     else fprintf(fd, "%g %g LT\n", xx, yy);
   }
-  if(fill && fill_type[c] && poly_fill) {
+  if(xctx->fill_pattern && fill_type[c] && poly_fill) {
     fprintf(fd, "C F S\n");
   } else {
     fprintf(fd, "S\n");
diff --git a/src/save.c b/src/save.c
index 1c471858..65c3abef 100644
--- a/src/save.c
+++ b/src/save.c
@@ -1143,7 +1143,7 @@ void push_undo(void)
     FILE *fd;
     char diff_name[PATH_MAX+100]; /* overflow safe 20161122 */
 
-    if(no_undo)return;
+    if(xctx->no_undo)return;
     dbg(1, "push_undo(): cur_undo_ptr=%d tail_undo_ptr=%d head_undo_ptr=%d\n",
        xctx->cur_undo_ptr, xctx->tail_undo_ptr, xctx->head_undo_ptr);
 
@@ -1153,7 +1153,7 @@ void push_undo(void)
     fd = popen(diff_name,"w");
     if(!fd) {
       fprintf(errfp, "push_undo(): failed to open write pipe %s\n", diff_name);
-      no_undo=1;
+      xctx->no_undo=1;
       return;
     }
     #elif HAS_PIPE==1
@@ -1190,7 +1190,7 @@ void push_undo(void)
     fd = fopen(diff_name,"w");
     if(!fd) {
       fprintf(errfp, "push_undo(): failed to open undo file %s\n", diff_name);
-      no_undo=1;
+      xctx->no_undo=1;
       return;
     }
     #endif
@@ -1218,7 +1218,7 @@ void pop_undo(int redo)
   FILE *diff_fd;
   #endif
 
-  if(no_undo)return;
+  if(xctx->no_undo)return;
   if(redo) {
     if(xctx->cur_undo_ptr < xctx->head_undo_ptr) {
       dbg(1, "pop_undo(): redo; cur_undo_ptr=%d tail_undo_ptr=%d head_undo_ptr=%d\n",
@@ -1247,7 +1247,7 @@ void pop_undo(int redo)
   fd=popen(diff_name, "r");
   if(!fd) {
     fprintf(errfp, "pop_undo(): failed to open read pipe %s\n", diff_name);
-    no_undo=1;
+    xctx->no_undo=1;
     return;
   }
   #elif HAS_PIPE==1
@@ -1281,7 +1281,7 @@ void pop_undo(int redo)
   fd=fopen(diff_name, "r");
   if(!fd) {
     fprintf(errfp, "pop_undo(): failed to open read pipe %s\n", diff_name);
-    no_undo=1;
+    xctx->no_undo=1;
     return;
   }
   #endif
diff --git a/src/scheduler.c b/src/scheduler.c
index fb091d94..2ba02309 100644
--- a/src/scheduler.c
+++ b/src/scheduler.c
@@ -316,7 +316,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       cmd_found = 1;
       if(argc==3) {
          debug_var=atoi(argv[2]);
-         tclsetvar("tcl_debug",argv[2]);
+         tclsetvar("debug_var",argv[2]);
       }
       Tcl_ResetResult(interp);
     }
@@ -702,7 +702,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
              change_to_unix_fn(s);
              int slen = strlen(s);
              if(s[slen - 1] == '/') s[slen - 1] = '\0';
-             strcpy(win_temp_dir, s);
+             my_strncpy(win_temp_dir, s, S(win_temp_dir));
              dbg(2, "scheduler(): win_temp_dir is %s\n", win_temp_dir);
              Tcl_SetResult(interp, s, TCL_VOLATILE);
            }
@@ -1064,8 +1064,8 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
     else if(!strcmp(argv[1],"hilight"))
     {
       cmd_found = 1;
-      enable_drill = 0;
-      if(argc >=3 && !strcmp(argv[2], "drill")) enable_drill = 1;
+      xctx->enable_drill = 0;
+      if(argc >=3 && !strcmp(argv[2], "drill")) xctx->enable_drill = 1;
       hilight_net(0);
       /* draw_hilight_net(1); */
       redraw_hilights(0);
@@ -1946,7 +1946,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
    
           my_strdup(371, &ptr,subst_token(xctx->inst[inst].prop_ptr, "name", name) );
           hash_all_names(inst);
-          new_prop_string(inst, ptr,0, dis_uniq_names); /* set new prop_ptr */
+          new_prop_string(inst, ptr,0, disable_unique_names); /* set new prop_ptr */
           my_strdup2(517, &newname, get_tok_value(xctx->inst[inst].prop_ptr, "name",0));
           my_strdup2(372, &xctx->inst[inst].instname, newname);
    
@@ -2142,7 +2142,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       cmd_found = 1;
       tcleval("info exists sim");
       if(tclresult()[0] == '1') exists = 1;
-      enable_drill = 0;
+      xctx->enable_drill = 0;
       if(exists) {
         viewer = atol(tclgetvar("sim(spicewave,default)"));
         my_snprintf(tcl_str, S(tcl_str), "sim(spicewave,%d,name)", viewer);
@@ -2179,7 +2179,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       #endif
       if(!strcmp(argv[2],"no_undo")) {
         int s = atoi(argv[3]);
-        no_undo=s;
+        xctx->no_undo=s;
       }
       else if(!strcmp(argv[2],"no_draw")) {
         int s = atoi(argv[3]);
@@ -2252,9 +2252,9 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       }
       else if(!strcmp(argv[2],"disable_unique_names")) {
         if(!strcmp(argv[3],"1")) {
-          dis_uniq_names=1;
+          disable_unique_names=1;
         } else {
-          dis_uniq_names=0;
+          disable_unique_names=0;
         }
       }
       else if(!strcmp(argv[2],"incr_hilight")) {
@@ -2399,9 +2399,9 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
         xctx->prep_hi_structs=0;
         if(!strcmp(argv[3], "name")) hash_all_names(inst);
         if(argc >= 5) {
-          new_prop_string(inst, subst_token(xctx->inst[inst].prop_ptr, argv[3], argv[4]),fast, dis_uniq_names);
+          new_prop_string(inst, subst_token(xctx->inst[inst].prop_ptr, argv[3], argv[4]),fast, disable_unique_names);
         } else {/* assume argc == 4 , delete attribute */
-          new_prop_string(inst, subst_token(xctx->inst[inst].prop_ptr, argv[3], NULL),fast, dis_uniq_names);
+          new_prop_string(inst, subst_token(xctx->inst[inst].prop_ptr, argv[3], NULL),fast, disable_unique_names);
         }
         my_strdup2(367, &xctx->inst[inst].instname, get_tok_value(xctx->inst[inst].prop_ptr, "name",0));
 
@@ -2520,7 +2520,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       xRect boundbox;
       int big =  xctx->wires> 2000 || xctx->instances > 2000 ;
       cmd_found = 1;
-      enable_drill=0;
+      xctx->enable_drill=0;
       if(!big) calc_drawing_bbox(&boundbox, 2);
       clear_all_hilights();
       /* undraw_hilight_net(1); */
diff --git a/src/spice_netlist.c b/src/spice_netlist.c
index 2f7f75f4..48b47078 100644
--- a/src/spice_netlist.c
+++ b/src/spice_netlist.c
@@ -129,7 +129,7 @@ void global_spice_netlist(int global)  /* netlister driver */
  top_subckt = 0;
  spiceprefix=1;
  bus_char[0] = bus_char[1] = '\0';
- hiersep[0]='.'; hiersep[1]='\0';
+ xctx->hiersep[0]='.'; xctx->hiersep[1]='\0';
  str_tmp = tclgetvar("bus_replacement_char");
  if(str_tmp && str_tmp[0] && str_tmp[1]) {
    bus_char[0] = str_tmp[0];
diff --git a/src/tedax_netlist.c b/src/tedax_netlist.c
index 6f4251f1..5f6d1450 100644
--- a/src/tedax_netlist.c
+++ b/src/tedax_netlist.c
@@ -40,7 +40,7 @@ void global_tedax_netlist(int global)  /* netlister driver */
  statusmsg("",2);  /* clear infowindow */
  record_global_node(2, NULL, NULL); /* delete list of global nodes */
  bus_char[0] = bus_char[1] = '\0';
- hiersep[0]='.'; hiersep[1]='\0';
+ xctx->hiersep[0]='.'; xctx->hiersep[1]='\0';
  str_tmp = tclgetvar("bus_replacement_char");
  if(str_tmp && str_tmp[0] && str_tmp[1]) {
    bus_char[0] = str_tmp[0];
@@ -130,7 +130,7 @@ void global_tedax_netlist(int global)  /* netlister driver */
 
  /* print globals nodes found in netlist 28032003 */
  record_global_node(0,fd,NULL);
- fprintf(fd, "__HIERSEP__ %s\n", hiersep);
+ fprintf(fd, "__HIERSEP__ %s\n", xctx->hiersep);
 
  dbg(1, "global_tedax_netlist(): starting awk on netlist!\n");
 
diff --git a/src/token.c b/src/token.c
index d868ef25..38d8fef3 100644
--- a/src/token.c
+++ b/src/token.c
@@ -194,7 +194,7 @@ void check_unique_names(int rename)
   if(xctx->hilight_nets) {
     xRect boundbox;
     if(!big) calc_drawing_bbox(&boundbox, 2);
-    enable_drill=0;
+    xctx->enable_drill=0;
     clear_all_hilights();
     /* undraw_hilight_net(1); */
     if(!big) {
@@ -500,7 +500,7 @@ const char *get_tok_value(const char *s,const char *tok, int with_quotes)
       if(!escape) quote=!quote;
     }
     if(state==TOK_TOKEN) {
-      if(!cmp) { /* previous token matched search and was without value, return get_tok_size */
+      if(!cmp) { /* previous token matched search and was without value, return xctx->get_tok_size */
         result[0] = '\0';
         return result;
       }
@@ -659,7 +659,7 @@ char *get_pin_attr_from_inst(int inst, int pin, const char *attr)
    return pin_attr_value; /* caller is responsible for freeing up storage for pin_attr_value */
 }
 
-void new_prop_string(int i, const char *old_prop, int fast, int dis_uniq_names)
+void new_prop_string(int i, const char *old_prop, int fast, int disable_unique_names)
 {
 /* given a old_prop property string, return a new */
 /* property string in xctx->inst[i].prop_ptr such that the element name is */
@@ -697,7 +697,7 @@ void new_prop_string(int i, const char *old_prop, int fast, int dis_uniq_names)
  }
  prefix=old_name[0];
  /* don't change old_prop if name does not conflict. */
- if(dis_uniq_names || (entry = inst_hash_lookup(table, old_name, i, XLOOKUP, old_name_len))==NULL ||
+ if(disable_unique_names || (entry = inst_hash_lookup(table, old_name, i, XLOOKUP, old_name_len))==NULL ||
      entry->value == i)
  {
   inst_hash_lookup(table, old_name, i, XINSERT, old_name_len);
@@ -2786,7 +2786,7 @@ const char *translate(int inst, const char* s)
  result[0]='\0';
 
  dbg(1, "translate(): substituting props in <%s>, instance <%s>\n",
-        s?s:"NULL",xctx->inst[inst].instname?xctx->inst[inst].instname:"NULL");
+        s ? s : "NULL" , xctx->inst[inst].instname ? xctx->inst[inst].instname : "NULL");
 
  while(1)
  {
diff --git a/src/xinit.c b/src/xinit.c
index cc244ec8..e45e5ab1 100644
--- a/src/xinit.c
+++ b/src/xinit.c
@@ -364,6 +364,7 @@ void free_xschem_data()
   for(i=0;i<CADMAXHIER;i++) my_free(1139, &xctx->sch_path[i]);
   my_free(1099, &xctx->gridpoint);
   my_free(1214, &xctx->biggridpoint);
+  my_free(1121, &xctx->active_layer);
   my_free(269, &xctx);
 }
 
@@ -446,6 +447,7 @@ void alloc_xschem_data()
   xctx->rx1 = xctx->rx2 = xctx->ry1 = xctx->ry2 = 0.0;
   xctx->move_rot = 0;
   xctx->move_flip = 0;
+  xctx->manhattan_lines = 0;
   xctx->x1 = xctx->y_1 = xctx->x2 = xctx->y_2 = xctx->deltax = xctx->deltay = 0.0;
   xctx->movelastsel = 0;
   xctx->rotatelocal=0;
@@ -521,6 +523,13 @@ void alloc_xschem_data()
   xctx->sel_array=my_calloc(619, xctx->maxsel, sizeof(Selected));
   xctx->biggridpoint=(XSegment*)my_calloc(1213, CADMAXGRIDPOINTS,sizeof(XSegment));
   xctx->gridpoint=(XPoint*)my_calloc(608, CADMAXGRIDPOINTS,sizeof(XPoint));
+  xctx->n_active_layers = 0;
+  xctx->active_layer=my_calloc(563, cadlayers, sizeof(int));
+  xctx->enable_drill = 0;
+  xctx->pending_fullzoom = 0;
+  my_strncpy(xctx->hiersep, ".", S(xctx->hiersep));
+  xctx->no_undo = 0;
+  xctx->fill_pattern = 1;
 }
 
 void alloc_data()
@@ -533,7 +542,6 @@ void alloc_data()
  gc=my_calloc(638, cadlayers, sizeof(GC));
  gcstipple=my_calloc(639, cadlayers, sizeof(GC));
  fill_type=my_calloc(640, cadlayers, sizeof(int));
- active_layer=my_calloc(563, cadlayers, sizeof(int));
  pixdata=my_calloc(641, cadlayers, sizeof(char*));
  for(i=0;i<cadlayers;i++)
  {
@@ -591,7 +599,6 @@ void xwin_exit(void)
    my_free(1102, &pixdata[i]);
  }
  my_free(1120, &fill_type);
- my_free(1121, &active_layer);
  my_free(1122, &pixdata);
  my_free(1123, &enable_layer);
  my_free(1135, &gc);
@@ -1035,9 +1042,9 @@ void resetwin(int create_pixmap, int clear_pixmap, int force, int w, int h)
         }
         if(create_pixmap) {
           #ifdef __unix__
-          xctx->save_pixmap = XCreatePixmap(display, xctx->window, xctx->xschem_w, xctx->xschem_h, depth);
+          xctx->save_pixmap = XCreatePixmap(display, xctx->window, xctx->xschem_w, xctx->xschem_h, screendepth);
           #else
-          xctx->save_pixmap = Tk_GetPixmap(display, xctx->window, xctx->xschem_w, xctx->xschem_h, depth);
+          xctx->save_pixmap = Tk_GetPixmap(display, xctx->window, xctx->xschem_w, xctx->xschem_h, screendepth);
           #endif
           xctx->gctiled = XCreateGC(display,xctx->window,0L, NULL);
           XSetTile(display,xctx->gctiled, xctx->save_pixmap);
@@ -1048,9 +1055,9 @@ void resetwin(int create_pixmap, int clear_pixmap, int force, int w, int h)
         }
       }
     }
-    if(pending_fullzoom) {
+    if(xctx->pending_fullzoom) {
       zoom_full(0, 0, 1, 0.97);
-      pending_fullzoom=0;
+      xctx->pending_fullzoom=0;
     }
     dbg(1, "resetwin(): Window reset\n");
   } /* end if(has_x) */
@@ -1380,8 +1387,8 @@ int Tcl_AppInit(Tcl_Interp *inter)
  init_pixdata();
  init_color_array(0.0);
  my_snprintf(tmp, S(tmp), "%d",debug_var);
- tclsetvar("tcl_debug",tmp );
- tclsetvar("menu_tcl_debug",debug_var ? "1" : "0" );
+ tclsetvar("debug_var",tmp );
+ tclsetvar("menu_debug_var",debug_var ? "1" : "0" );
  if(flat_netlist) tclsetvar("flat_netlist","1");
 
  xctx->xschem_w = CADWIDTH;
@@ -1472,8 +1479,8 @@ int Tcl_AppInit(Tcl_Interp *inter)
 
     screen_number = Tk_ScreenNumber(mainwindow);
     colormap = Tk_Colormap(mainwindow);
-    depth = Tk_Depth(mainwindow);
-    dbg(1, "Tcl_AppInit(): screen depth: %d\n",depth);
+    screendepth = Tk_Depth(mainwindow);
+    dbg(1, "Tcl_AppInit(): screen depth: %d\n",screendepth);
     visual = Tk_Visual(mainwindow);
 
     /*
@@ -1615,7 +1622,7 @@ int Tcl_AppInit(Tcl_Interp *inter)
  zoom_full(0, 0, 1, 0.97);   /* Necessary to tell xschem the
                   * initial area to display
                   */
- pending_fullzoom=1;
+ xctx->pending_fullzoom=1;
  if(do_netlist) {
    if(debug_var>=1) {
      if(flat_netlist)
diff --git a/src/xschem.h b/src/xschem.h
index 7497ffae..94bff077 100644
--- a/src/xschem.h
+++ b/src/xschem.h
@@ -245,7 +245,7 @@ extern char win_temp_dir[PATH_MAX];
 #define ABORT  512 /*  used in move/copy_objects for aborting without unselecting */
 #define THICK 1024 /*  used to draw thick lines (buses) */
 #define ROTATELOCAL 2048 /*  rotate each selected object around its own anchor point 20171208 */
-#define CLEAR 4096 /* used in new_wire to clear previous rubber when switching manhattan_lines */
+#define CLEAR 4096 /* used in new_wire to clear previous rubber when switching xctx->manhattan_lines */
 /* #define DRAW 8192 */  /* was used in bbox() to draw things by using XCopyArea after setting clip rectangle */
 #define HILIGHT 8192  /* used when calling draw_*symbol_outline() for hilighting instead of normal draw */
 #define FONTWIDTH 20
@@ -605,6 +605,7 @@ typedef struct {
   double rx1, rx2, ry1, ry2;
   short move_rot;
   short move_flip;
+  int manhattan_lines;
   double x1, y_1, x2, y_2, deltax, deltay;
   int movelastsel;
   short rotatelocal;
@@ -625,6 +626,13 @@ typedef struct {
   XSegment *biggridpoint;
   XPoint *gridpoint;
   char plotfile[PATH_MAX];
+  int *active_layer;
+  int n_active_layers;
+  int enable_drill;
+  int pending_fullzoom;
+  char hiersep[20];
+  int no_undo;
+  int fill_pattern; /*  fill rectangles */
 } Xschem_ctx;
 
 struct Lcc { /* used for symbols containing schematics as instances (LCC, Local Custom Cell) */
@@ -702,18 +710,55 @@ struct instentry {
 
 /* GLOBAL VARIABLES */
 extern Xschem_ctx *xctx;
+/*********** Variables backed in xschem.tcl ***********/
+extern int cadlayers; 
+extern int has_x; 
+extern int rainbow_colors; 
+extern int persistent_command; 
+extern int autotrim_wires; 
+extern int disable_unique_names; 
+extern int change_lw; /* allow change line width*/
+extern int incr_hilight; 
+extern int auto_hilight; 
+extern int big_grid_points; 
+extern int draw_grid; 
+extern double cadgrid; 
+extern double cadsnap; 
+extern int draw_window; 
+extern unsigned short enable_stretch; 
+extern int split_files; 
+extern char *netlist_dir; 
+extern int sym_txt; 
+extern int fullscreen; 
+extern int en_hilight_conn_inst; 
+extern int transparent_svg; 
+extern int color_ps; 
+extern int only_probes; 
+extern int unzoom_nodrift; 
+extern int spiceprefix; 
+extern int netlist_show; 
+extern double nocairo_vert_correct;
+extern double nocairo_font_xscale;
+extern double nocairo_font_yscale;
+extern char svg_font_name[80];
+extern int top_subckt;
+extern int constrained_move;
+extern int netlist_type;
+extern int dark_colorscheme;
+extern int flat_netlist;
+extern int hide_symbols; /* draw only a bounding box for component instances and @symname, @name texts */
+extern int show_pin_net_names;
+extern int *enable_layer;
+extern double cairo_font_scale; /*  default: 1.0, allows to adjust font size */
+extern char cairo_font_name[80];
+extern double cairo_font_line_spacing; /*  allows to change line spacing: default: 1.0 */
+extern double cairo_vert_correct;
+extern int debug_var;
+/*********** End of variables backed in xschem.tcl ***********/
 extern int help;
 extern char *cad_icon[];
-extern int manhattan_lines;
-extern int cadlayers;
-extern int *active_layer;
-extern int *enable_layer;
-extern int n_active_layers;
 extern int do_print;
-extern int has_x;
 extern int no_draw;
-extern int sym_txt;
-extern int rainbow_colors;
 extern FILE *errfp;
 extern int no_readline;
 extern char *filename;
@@ -724,36 +769,18 @@ extern int load_initfile;
 extern char rcfile[PATH_MAX];
 extern char *tcl_command;
 extern char tcl_script[PATH_MAX];
-extern int persistent_command;
-extern int autotrim_wires;
-extern int dis_uniq_names;
-
 extern int tcp_port;
-extern int debug_var;
 extern char **color_array;
 extern unsigned int color_index[];
-extern int change_lw; /*  allow change line width */
-extern int thin_text;
-extern int incr_hilight;
-extern int auto_hilight;
-extern int fill; /*  fill rectangles */
-extern int draw_grid;
-extern int big_grid_points;
 extern int text_svg;
 extern int text_ps;
-extern double cadgrid;
 extern double cadhalfdotsize;
-extern int draw_pixmap; /*  pixmap used as 2nd buffer */
-extern int draw_window;
+extern int draw_pixmap; /* pixmap used as 2nd buffer */
 extern XEvent xev;
 extern KeySym key;
-extern unsigned short enable_stretch;
 extern unsigned int button;
 extern unsigned int state; /*  status of shift,ctrl etc.. */
-extern int currentsch;
 extern char *xschem_version_string;
-extern int split_files;
-extern char *netlist_dir;
 extern char initial_netlist_name[PATH_MAX];
 extern char bus_char[];
 extern int max_undo;
@@ -761,49 +788,19 @@ extern int draw_dots;
 extern int draw_single_layer;
 extern int yyparse_error;
 extern char *xschem_executable;
-extern int depth;
+extern int screendepth;
 extern int *fill_type; /* 20171117 for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
 extern Tcl_Interp *interp;
-extern double cadsnap;
 extern double *character[256];
-extern int constrained_move;
-extern int netlist_show;
-extern int flat_netlist;
-extern int netlist_type;
 extern int do_netlist;
 extern int do_simulation;
 extern int do_waves;
 extern int netlist_count;
-extern int top_subckt;
-extern int spiceprefix;
-extern char hiersep[20];
 extern int quit;
 extern int show_erc;
-extern int color_ps;
-extern int transparent_svg;
-extern int only_probes;
-extern int pending_fullzoom;
-extern int fullscreen;
-extern int unzoom_nodrift;
-extern int dark_colorscheme;
 extern double color_dim;
-extern int no_undo;
-extern int enable_drill;
-extern size_t get_tok_size;
 extern int batch_mode; /* no TCL console */
-extern int hide_symbols; /* draw only a bounding box for component instances and @symname, @name texts */
-extern int show_pin_net_names;
-extern int en_hilight_conn_inst;
-extern char svg_font_name[80];
-/* CAIRO specific global variables */
-extern char cairo_font_name[80];
-extern double cairo_font_scale; /*  default: 1.0, allows to adjust font size */
-extern double nocairo_font_xscale;
-extern double nocairo_font_yscale;
-extern double cairo_font_line_spacing; /*  allows to change line spacing: default: 1.0 */
-extern double cairo_vert_correct;
-extern double nocairo_vert_correct;
-extern const char fopen_read_mode[];
+extern const char fopen_read_mode[]; /* "r" on unix, "rb" on windows */
 
 /* X11 specific globals */
 extern Colormap colormap;
@@ -1099,7 +1096,7 @@ extern void *my_calloc(int id, size_t nmemb, size_t size);
 extern void my_free(int id, void *ptr);
 extern size_t my_strcat(int id, char **, const char *);
 extern const char *subst_token(const char *s, const char *tok, const char *new_val);
-extern void new_prop_string(int i, const char *old_prop,int fast, int dis_uniq_names);
+extern void new_prop_string(int i, const char *old_prop,int fast, int disable_unique_names);
 extern void hash_name(char *token, int remove);
 extern void hash_all_names(int n);
 extern void symbol_bbox(int i, double *x1,double *y1, double *x2, double *y2);
diff --git a/src/xschem.tcl b/src/xschem.tcl
index ca269b30..09d4029a 100644
--- a/src/xschem.tcl
+++ b/src/xschem.tcl
@@ -131,10 +131,10 @@ proc execute {status args} {
 
 proc netlist {source_file show netlist_file} {
  global XSCHEM_SHAREDIR flat_netlist hspice_netlist netlist_dir
- global verilog_2001 netlist_type tcl_debug
+ global verilog_2001 netlist_type debug_var
  
  simuldir
- if {$tcl_debug <= -1} { puts "netlist: source_file=$source_file, netlist_type=$netlist_type" }
+ if {$debug_var <= -1} { puts "netlist: source_file=$source_file, netlist_type=$netlist_type" }
  if {$netlist_type eq {spice}} {
    if { $hspice_netlist == 1 } {
      set simulator {-hspice}
@@ -216,7 +216,7 @@ proc convert_to_pdf {filename dest} {
 
 # 20161121
 proc convert_to_png {filename dest} {
-  global to_png tcl_debug
+  global to_png debug_var
   # puts "---> $to_png $filename $dest"
   set cmd "exec $to_png \$filename png:\$dest"
     if {$::OS == "Windows"} {
@@ -1010,7 +1010,7 @@ proc waves {} {
 # ============================================================
 
 proc utile_translate {schname} { 
-  global netlist_dir netlist_type tcl_debug XSCHEM_SHAREDIR
+  global netlist_dir netlist_type debug_var XSCHEM_SHAREDIR
   global utile_gui_path utile_cmd_path
 
   simuldir 
@@ -1020,7 +1020,7 @@ proc utile_translate {schname} {
 }
 
 proc utile_gui {schname} { 
-  global netlist_dir netlist_type tcl_debug XSCHEM_SHAREDIR
+  global netlist_dir netlist_type debug_var XSCHEM_SHAREDIR
   global utile_gui_path utile_cmd_path
 
   simuldir 
@@ -1030,7 +1030,7 @@ proc utile_gui {schname} {
 }
 
 proc utile_edit {schname} { 
-  global netlist_dir netlist_type tcl_debug editor XSCHEM_SHAREDIR
+  global netlist_dir netlist_type debug_var editor XSCHEM_SHAREDIR
   global utile_gui_path utile_cmd_path
 
   simuldir
@@ -1040,7 +1040,7 @@ proc utile_edit {schname} {
 }
 
 proc get_shell { curpath } {
- global netlist_dir netlist_type tcl_debug
+ global netlist_dir netlist_type debug_var
  global  terminal
 
  simuldir
@@ -1048,7 +1048,7 @@ proc get_shell { curpath } {
 }
 
 proc edit_netlist {schname } {
- global netlist_dir netlist_type tcl_debug
+ global netlist_dir netlist_type debug_var
  global editor terminal
 
  simuldir
@@ -2111,7 +2111,7 @@ proc property_search {} {
     button .dialog.but.ok -text OK -command {
           set search_value [.dialog.val.e get]
           set custom_token [.dialog.custom.e get]
-          if {$tcl_debug<=-1} { puts stderr "|$custom_token|" }
+          if {$debug_var<=-1} { puts stderr "|$custom_token|" }
           set token $custom_token
           if { $search_exact==1 } {
             set search_found [xschem searchmenu exact $search_select $token $search_value]
@@ -2163,12 +2163,12 @@ proc property_search {} {
 #
 proc tclpropeval {s instname symname} {
   # puts "tclpropeval: $s $instname $symname"
-  global env tcl_debug
-  if {$tcl_debug <=-1} {puts "tclpropeval: $s"}
+  global env debug_var
+  if {$debug_var <=-1} {puts "tclpropeval: $s"}
   regsub {^@tcleval\(} $s {} s
   regsub {\)([ \t\n]*)$} $s {\1} s
   if { [catch {eval $s} res] } {
-    if { $tcl_debug<=-1 } { puts "tclpropeval warning: $res"}
+    if { $debug_var<=-1 } { puts "tclpropeval warning: $res"}
     set res ?\n
   }
   return $res
@@ -2176,21 +2176,21 @@ proc tclpropeval {s instname symname} {
 
 # this hook is called in translate() if whole string is contained in a tcleval(...) construct
 proc tclpropeval2 {s} {
-  global tcl_debug env netlist_type path
+  global debug_var env netlist_type path
   # puts "tclpropeval2: s=|$s|"
-  if {$tcl_debug <=-1} {puts "tclpropeval2: $s"}
+  if {$debug_var <=-1} {puts "tclpropeval2: $s"}
   set path [string range [xschem get sch_path] 1 end]
   if { $netlist_type eq {spice} } {
     regsub {^([^xX])} $path {x\1} path
     while { [regsub {\.([^xX])} $path {.x\1} path] } {}
   }
-  if { $tcl_debug<=-1 } { puts "---> path=$path" }
+  if { $debug_var<=-1 } { puts "---> path=$path" }
   regsub {^tcleval\(} $s {} s
   regsub {\)([ \n\t]*)$} $s {\1} s
   # puts "tclpropeval2: s=|$s|"
   # puts "tclpropeval2: subst $s=|[subst $s]|"
   if { [catch {uplevel #0 "subst \{$s\}"} res] } {
-    if { $tcl_debug<=-1 } { puts "tclpropeval2 warning: $res"}
+    if { $debug_var<=-1 } { puts "tclpropeval2 warning: $res"}
     set res ?\n
   }
   # puts "tclpropeval2: res=|$res|"
@@ -2292,7 +2292,7 @@ proc ask_save { {ask {save file?}} } {
 
 
 proc edit_vi_prop {txtlabel} {
-  global XSCHEM_TMP_DIR retval symbol prev_symbol rcode tcl_debug netlist_type editor
+  global XSCHEM_TMP_DIR retval symbol prev_symbol rcode debug_var netlist_type editor
   global user_wants_copy_cell
  
   set user_wants_copy_cell 0
@@ -2303,14 +2303,14 @@ proc edit_vi_prop {txtlabel} {
   write_data $retval $XSCHEM_TMP_DIR/$filename
   # since $editor can be an executable with options (gvim -f) I *need* to use eval
   eval execute_wait 0 $editor $XSCHEM_TMP_DIR/$filename ;# 20161119
-  if {$tcl_debug<=-1} {puts "edit_vi_prop{}:\n--------\nretval=$retval\n---------\n"}
-  if {$tcl_debug<=-1} {puts "edit_vi_prop{}:\n--------\nsymbol=$symbol\n---------\n"}
+  if {$debug_var<=-1} {puts "edit_vi_prop{}:\n--------\nretval=$retval\n---------\n"}
+  if {$debug_var<=-1} {puts "edit_vi_prop{}:\n--------\nsymbol=$symbol\n---------\n"}
   set tmp [read_data $XSCHEM_TMP_DIR/$filename]
   file delete $XSCHEM_TMP_DIR/$filename
-  if {$tcl_debug<=-1} {puts "edit_vi_prop{}:\n--------\n$tmp\n---------\n"}
+  if {$debug_var<=-1} {puts "edit_vi_prop{}:\n--------\n$tmp\n---------\n"}
   if [string compare $tmp $retval] {
          set retval $tmp
-         if {$tcl_debug<=-1} {puts "modified"}
+         if {$debug_var<=-1} {puts "modified"}
          set rcode ok
          return  $rcode
   } else {
@@ -2320,7 +2320,7 @@ proc edit_vi_prop {txtlabel} {
 }
 
 proc edit_vi_netlist_prop {txtlabel} {
-  global XSCHEM_TMP_DIR retval rcode tcl_debug netlist_type editor
+  global XSCHEM_TMP_DIR retval rcode debug_var netlist_type editor
   global user_wants_copy_cell
  
   set user_wants_copy_cell 0
@@ -2333,15 +2333,15 @@ proc edit_vi_netlist_prop {txtlabel} {
   if { [regexp vim $editor] } { set ftype "\{-c :set filetype=$netlist_type\}" } else { set ftype {} }
   # since $editor can be an executable with options (gvim -f) I *need* to use eval
   eval execute_wait 0 $editor  $ftype $XSCHEM_TMP_DIR/$filename
-  if {$tcl_debug <= -1}  {puts "edit_vi_prop{}:\n--------\n$retval\n---------\n"}
+  if {$debug_var <= -1}  {puts "edit_vi_prop{}:\n--------\n$retval\n---------\n"}
   set tmp [read_data $XSCHEM_TMP_DIR/$filename]
   file delete $XSCHEM_TMP_DIR/$filename
-  if {$tcl_debug <= -1}  {puts "edit_vi_prop{}:\n--------\n$tmp\n---------\n"}
+  if {$debug_var <= -1}  {puts "edit_vi_prop{}:\n--------\n$tmp\n---------\n"}
   if [string compare $tmp $retval] {
          set retval $tmp
          regsub -all {(["\\])} $retval {\\\1} retval ;#"  editor is confused by the previous quote
          set retval \"${retval}\" 
-         if {$tcl_debug <= -1}  {puts "modified"}
+         if {$debug_var <= -1}  {puts "modified"}
          set rcode ok
          return  $rcode
   } else {
@@ -2386,12 +2386,12 @@ proc change_color {} {
 
 proc edit_prop {txtlabel} {
   global edit_prop_size infowindow_text selected_tok edit_symbol_prop_new_sel edit_prop_pos
-  global prev_symbol retval symbol rcode no_change_attrs preserve_unchanged_attrs copy_cell tcl_debug
+  global prev_symbol retval symbol rcode no_change_attrs preserve_unchanged_attrs copy_cell debug_var
   global user_wants_copy_cell editprop_sympath retval_orig old_selected_tok
   set user_wants_copy_cell 0
   set rcode {}
   set retval_orig $retval
-  if {$tcl_debug <= -1}  {puts " edit_prop{}: retval=$retval"}
+  if {$debug_var <= -1}  {puts " edit_prop{}: retval=$retval"}
   if { [winfo exists .dialog] } return
   toplevel .dialog  -class Dialog 
   wm title .dialog {Edit Properties}
@@ -2609,11 +2609,11 @@ proc write_data {data f} {
 
 proc text_line {txtlabel clear {preserve_disabled disabled} } {
   global text_line_default_geometry preserve_unchanged_attrs
-  global retval rcode tcl_debug selected_tok retval_orig old_selected_tok
+  global retval rcode debug_var selected_tok retval_orig old_selected_tok
   set retval_orig $retval
   if $clear==1 then {set retval ""}
-  if {$tcl_debug <= -1}  {puts " text_line{}: clear=$clear"}
-  if {$tcl_debug <= -1}  {puts " text_line{}: retval=$retval"}
+  if {$debug_var <= -1}  {puts " text_line{}: clear=$clear"}
+  if {$debug_var <= -1}  {puts " text_line{}: retval=$retval"}
   set rcode {}
   if { [winfo exists .dialog] } return
   toplevel .dialog  -class Dialog
@@ -3410,8 +3410,8 @@ proc build_windows {} {
     pack .menubar -anchor n -side top -fill x  -before .drw
     toolbar_show
     pack .statusbar -after .drw -anchor sw  -fill x 
-    bind .statusbar.5 <Leave> { xschem set cadgrid $grid; focus .drw}
-    bind .statusbar.3 <Leave> { xschem set cadsnap $snap; focus .drw}
+    bind .statusbar.5 <Leave> { xschem set cadgrid $cadgrid; focus .drw}
+    bind .statusbar.3 <Leave> { xschem set cadsnap $cadsnap; focus .drw}
     set_bindings {.drw}
   }
 }
@@ -3558,9 +3558,9 @@ if {$::OS == "Windows"} {
 # used in C code
 set_ne xschem_libs {}
 set_ne noprint_libs {}
-set_ne tcl_debug 0
+set_ne debug_var 0
 # used to activate debug from menu
-set_ne menu_tcl_debug 0
+set_ne menu_debug_var 0
 set textwindow_wcounter 1
 set viewdata_wcounter 1
 set retval ""
@@ -3609,8 +3609,8 @@ set_ne enable_stretch 0
 set_ne constrained_move 0
 set_ne draw_grid 1
 set_ne big_grid_points 0
-set_ne snap 10
-set_ne grid 20
+set_ne cadsnap 10
+set_ne cadgrid 20
 set_ne persistent_command 0
 set_ne autotrim_wires 0
 set_ne disable_unique_names 0
@@ -3897,9 +3897,9 @@ if { ( $::OS== "Windows" || [string length [lindex [array get env DISPLAY] 1] ]
      -command {
         if { $transparent_svg==1 } {xschem set transparent_svg 1} else { xschem set transparent_svg 0}
      }
-  .menubar.option.menu add checkbutton -label "Debug mode" -variable menu_tcl_debug \
+  .menubar.option.menu add checkbutton -label "Debug mode" -variable menu_debug_var \
      -command {
-        if { $menu_tcl_debug==1 } {xschem debug 1} else { xschem debug 0}
+        if { $menu_debug_var==1 } {xschem debug 1} else { xschem debug 0}
      }
   .menubar.option.menu add checkbutton -label "Enable stretch" -variable enable_stretch \
      -accelerator Y \
@@ -4083,7 +4083,7 @@ if { ( $::OS== "Windows" || [string length [lindex [array get env DISPLAY] 1] ]
        }
   .menubar.zoom.menu add command -label "Set grid spacing" \
        -command {
-         input_line "Enter grid spacing (float):" "xschem set cadgrid" $grid
+         input_line "Enter grid spacing (float):" "xschem set cadgrid" $cadgrid
        }
   .menubar.zoom.menu add checkbutton -label "View only Probes" -variable only_probes \
          -accelerator {5} \
@@ -4302,10 +4302,10 @@ if { ( $::OS== "Windows" || [string length [lindex [array get env DISPLAY] 1] ]
   frame .statusbar  
   label .statusbar.1   -text "STATUS BAR 1"  
   label .statusbar.2   -text "SNAP:"
-  entry .statusbar.3 -textvariable snap -relief sunken -bg white \
+  entry .statusbar.3 -textvariable cadsnap -relief sunken -bg white \
          -width 10 -foreground black -takefocus 0
   label .statusbar.4   -text "GRID:"
-  entry .statusbar.5 -textvariable grid -relief sunken -bg white \
+  entry .statusbar.5 -textvariable cadgrid -relief sunken -bg white \
          -width 10 -foreground black -takefocus 0
   label .statusbar.6   -text "NETLIST MODE:"
   entry .statusbar.7 -textvariable netlist_type -relief sunken -bg white \