Index: win/tclWinFCmd.c
===================================================================
RCS file: /cvsroot/tcl/tcl/win/tclWinFCmd.c,v
retrieving revision 1.14
diff -u -r1.14 tclWinFCmd.c
--- win/tclWinFCmd.c	2001/09/28 11:10:56	1.14
+++ win/tclWinFCmd.c	2001/10/19 22:55:46
@@ -446,6 +446,20 @@
 	Tcl_SetErrno(ENOENT);
         return TCL_ERROR;
     }
+
+    /*
+     * Similarly, if 'nativeSrc' is NULL or empty, the following code
+     * locks up the process on WinNT; bail out.
+     */
+
+    if ( nativeSrc == NULL || nativeSrc[0] == '\0' ) {
+	Tcl_SetErrno( ENOENT );
+	return TCL_ERROR;
+    }
+
+    /*
+     * OK, now try the copy.
+     */
     
     __try {
 	if ((*tclWinProcs->copyFileProc)(nativeSrc, nativeDst, 0) != FALSE) {
