diff -rc tcsh-6.14.00/ed.chared.c tcsh-preserve-mark/ed.chared.c
*** tcsh-6.14.00/ed.chared.c	2005-03-03 08:21:08.000000000 -0800
--- tcsh-mark-bugfix/ed.chared.c	2006-01-08 18:03:54.000000000 -0800
***************
*** 206,212 ****
  		*cp = cp[num];
  	LastChar -= num;
  	if (Mark && Mark > Cursor)
! 		Mark -= num;
      }
  #ifdef notdef
      else {
--- 206,212 ----
  		*cp = cp[num];
  	LastChar -= num;
  	if (Mark && Mark > Cursor)
! 		Mark = Cursor;
      }
  #ifdef notdef
      else {
***************
*** 245,252 ****
  		*cp = cp[num];
  	LastChar -= num;
  	Cursor -= num;
! 	if (Mark && Mark > Cursor)
! 		Mark -= num;
      }
  }
  
--- 245,254 ----
  		*cp = cp[num];
  	LastChar -= num;
  	Cursor -= num;
! 	if (Mark > Cursor + num)
! 	    Mark -= num;
! 	else if (Mark > Cursor)
! 	    Mark = Cursor;
      }
  }
  
***************
*** 2589,2596 ****
      USE(c);
      c_push_kill(InputBuf, Cursor); /* copy it */
      c_delbefore((int)(Cursor - InputBuf));
-     if (Mark && Mark > Cursor)
-         Mark -= Cursor-InputBuf;
      return(CC_REFRESH);
  }
  
--- 2591,2596 ----