egAttr()

         Gets/Sets the RGB values of an attribute for all palettes

    Syntax:

         egAttr( cColor, [cNewRGB] ) -> cOldRGB

         cColor  : The colour to change or return expressed in CA-Clipper
                   sintaxis:

                   "N"  "B"  "G"  "BG"  "R"  "RB"  "GR"  "W",
                   "N+" "B+" "G+" "BG+" "R+" "RB+" "GR+" "W+"

         cNewRGB : A 48 bytes string defining the new values of red, green
                   and blue for the colour. For example:

                          Palette 0                  Palette 15
                       Red Green Blue   ... ...  Red Green Blue

                   being each colour a byte size.

    Description:

         Lets change the basic colour definition for all the palettes.

    Return:

         Returns a 48 byte string with the actual definition of red, green
         and blue of a colour for all the palettes.

    Ejemplos:

         cColor := Replicate ( Chr( 63 ) + Chr( 0 ) + Chr( 0 ), 16 )
         egAttr( "N", cColor )   // change black to red