VMS Help CC, Run-time functions, [w]addch  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Curses Screen Management function and macro that add the character
  ch to the window at the current position of the cursor.  The addch
  macro operates on the stdscr window.

  Syntax:

       #include <curses.h>

       int addch(char ch);
       int waddch(WINDOW *win, char ch);