Implement -autoCopyPV

This option causes automatic copying of the last position of a PV walk
to the clipboard.

args.h

@@ -651,6 +651,7 @@ ArgDescriptor argDescriptors[] = {
   { "findMirrorImage", ArgBoolean, (void *) &appData.findMirror, FALSE, FALSE },
   { "viewer", ArgTrue, (void *) &appData.viewer, FALSE, FALSE },
   { "viewerOptions", ArgString, (void *) &appData.viewerOptions, TRUE, (ArgIniType) "-ncp -engineOutputUp false -saveSettingsOnExit false" },
+  { "autoCopyPV", ArgBoolean, (void *) &appData.autoCopyPV, TRUE, FALSE },
 
 #if ZIPPY
   { "zippyTalk", ArgBoolean, (void *) &appData.zippyTalk, FALSE, (ArgIniType) ZIPPY_TALK },

backend.c

@@ -5451,6 +5451,7 @@ UnLoadPV ()
 {
   int oldFMM = forwardMostMove; // N.B.: this was currentMove before PV was loaded!
   if(endPV < 0) return;
+  if(appData.autoCopyPV) CopyFENToClipboard();
   endPV = -1;
   if(gameMode == AnalyzeMode && currentMove > forwardMostMove) {
 	Boolean saveAnimate = appData.animate;

common.h

@@ -664,6 +664,7 @@ typedef struct {
     int evalThreshold;  /* [HGM] evalGraph */
     Boolean dropMenu;   /* [HGM] pv        */
     Boolean markers;    /* [HGM] markers   */
+    Boolean autoCopyPV;
     Boolean pieceMenu;
     Boolean sweepSelect;
     Boolean whitePOV;

frontend.h

@@ -208,6 +208,7 @@ void HistorySet P((char movelist[][2*MOVE_LEN], int first, int last, int current
 void FreezeUI P((void));
 void ThawUI P((void));
 void ChangeDragPiece P((ChessSquare piece));
+void CopyFENToClipboard P((void));
 extern char *programName;
 extern int commentUp;
 extern char *firstChessProgramNames;

xboard.c

@@ -5617,6 +5617,12 @@ CopyPositionProc (Widget w, XEvent *event, String *prms, Cardinal *nprms)
 		   NULL/* transfer_done_proc */);
 }
 
+void
+CopyFENToClipboard ()
+{ // wrapper to make call from back-end possible
+  CopyPositionProc(NULL, NULL, NULL, NULL);
+}
+
 /* function called when the data to Paste is ready */
 static void
 PastePositionCB (Widget w, XtPointer client_data, Atom *selection,

xboard.texi

@@ -3126,6 +3126,13 @@ loaded game.  Default: true.
 If this option is set to true, the Paste Position and Paste Game
 options paste from the currently selected text.  If false, they paste
 from the clipboard.  Default: false.
+@item -autoCopyPV true|false
+@cindex autoCopyPV, option
+When this option is set, the position displayed on the board when
+you terminate a PV walk 
+(initiated by a right-click on board or engine-output window)
+will be automatically put on the clipboard as FEN.
+Default: false.
 @item -dropMenu true|false
 @cindex dropMenu, option
 This option allows you to emulate old behavior,