WSETSHADOW()
 Sets the window shadow colors
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 Syntax

     WSETSHADOW([<cAttribute>]) --> nOldAttribute

 Argument

     <cAttribute>  Designates the color attribute for window shadows.  It
     can be represented  as a numeric string ("nn/nn") or as a color string
     ("cc/cc").  A value of -1 turns off the shadow display.

     ()  When you call the function without parameters, it returns the
     current shadow color setting.

 Returns

     WSETSHADOW() returns the previously set shadow color, or it returns -1
     if no shadow color has been set.

 Description

     WSETSHADOW() sets individual color attributes for shadows of every
     window, which are displayed below and to the right of each window.  The
     WSETSHADOW() setting then applies to all subsequently opened windows.

 Notes

     .  When you use shadows, the window screen area is erased during
        opening.

     .  The proportions of the right and lower shadows are adapted to
        the height of the characters.  For example, the proportion is  2:1
        with 25 rows; and the proportion is  1:1 with 50 rows.

 Example

     In order to experiment with shadows, you should first fill the screen
     with a character like CHR(176):

     SETCLEARB(176)
     CLEAR                    // Fill screen with CHR(176)

     WSETSHADOW("N+")         // Gray shadows
     WOPEN(1, 1, 10, 50)
     WBOX()

     WSETSHADOW(-1)           // Switch shadow display off
     WOPEN(15, 1, 20, 50)
     WBOX()

     INKEY(0)                 // Switch on move mode using
                              // SCROLL-LOCK

     WACLOSE()