--- a/WinWorkstation.st	Fri Mar 25 06:41:01 2016 +0000
+++ b/WinWorkstation.st	Mon Mar 28 00:38:27 2016 +0100
@@ -8079,6 +8079,58 @@
     self removeKnownView:aView withId:aWindowId
 !
 
+dcLockForGC:gcId
+    "Locks and return a device context for given GC.
+     Returned DeviceContext is associated with given GC and it's
+     guaranteed not to be destroyed (by ReleaseDC()) until
+     #dcUnlockForGC: is called. 
+
+     NOTE: The DC __is__ destroyed, however, when the whole
+     GC is destroyed."
+
+     | error |
+%{
+    if (__isExternalAddress(gcId)) {
+        struct gcData *gc = _GCDATA(gcId);
+        HDC hDC;
+        if (! gc->_hDC) {
+            hDC = _getDC(gc);            
+            gc->_hDC = hDC;
+        } else {
+            hDC = gc->_hDC;
+        }
+        gc->doNotCacheOrRelease = 1;
+        RETURN ( __MKEXTERNALADDRESS ( hDC ) );
+    }
+    error = @symbol(BadArg1);
+    err:;
+%}.
+    ^ self primitiveFailed: error
+!     
+
+dcUnlockForGC:gcId
+    "Unlocks and __destroy__ a device context for given GC previously
+     locked by #dcLockForGC:. If the GC was not locked,
+     calling this method is no-op."
+
+     | error |
+%{
+    if (__isExternalAddress(gcId)) {
+        struct gcData *gc = _GCDATA(gcId);                
+        if (gc->hWnd) {
+            gc->doNotCacheOrRelease = 0;
+            if (gc->_hDC) {                        
+                _releaseDC(gc);
+            }                    
+        }
+        RETURN ( nil );
+    }
+    error = @symbol(BadArg1);
+    err:;
+%}.
+    ^ self primitiveFailed: error
+!     
+
 gcFor:aDrawableId
 
 %{  /* NOCONTEXT */
@@ -8179,19 +8231,6 @@
 %}
 !
 
-hdcForGC: gcId
-    "Private. Return a HDC (as ExternalAddress) associated with
-     given GC"
-%{
-    if (__isExternalAddressLike(gcId)) {
-    	HDC dc = _getDC ( _GCDATA(gcId) );
-    	_GCDATA(gcId)->doNotCacheOrRelease = 1;
-        RETURN ( __MKEXTERNALADDRESS ( dc ) );
-    }	
-%}.
-    self primitiveFailed.
-!
-
 primCreateBitmapFromArray:anArray width:w height:h
 %{