FT_CLS()
 Clear screen
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 Syntax

      FT_CLS( <nTRow>, <nLCol>, <nBRow>, <nRCol>, <nColor> ) -> NIL

 Arguments

     <nTRow>, <nLCol>, <nBRow> and  <nRCol> are the screen coordinates
     to clear.

     <nColor> is an integer representing the color attribute.
     The formula is:

       nFore + ( nBack * 16 )

     The default is black.

 Returns

     NIL

 Description

     This is a high speed function to clear the screen at the given
     coordinates with the given color attribute.  This does not change
     Clipper's color settings.  It uses direct video writes for speed.

 Examples

     FT_CLS( 0, 0, MaxRow(), MaxCol(), 165 )

     This example will clear the entire screen with the colors
     bright white on magenta.

 Source: VIDEO1.C

 Author: Robert A. DiFalco