twType( nRow, nCol, cString, cAttr, Sound )
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     Displays a string starting at specified relative window
     coordinates in a chosen colour, one character at a time, with or
     without accompanying typewriter sound.

       Arguments:

     nRow,nCol   - 'N' Relative Window Coordinates. Default to 1.

     cString     - 'C' The string to be displayed. Must be passed.

     cAttr       - 'C' Clipper colour attribute. Defaults to
                       SETCOLOR().

     Sound       - 'L' .T. for sound, .F. for silent.  Defaults to .T.

       Return:

     Current window handle.

       Example:

     twType( 19, 17, "Scrolling your screen  can", "", .T. )

     Types the string to the screen emulating typewriter sound, in the
     current window colour.

     twType( 19, 17, "Scrolling your screen  can", "b+/w", .F.)

     Types the string silently to the screen, in bright blue/white.