FXCOLOR is designed for Clipper version 5.01.  It has not been tested
   with other versions and may or may not be compatible.  It requires a VGA
   system and will not install itself unless a VGA is detected.  It is
   designed to work with color systems.  The effects on a non-color system
   has not been tested.

   FXCOLOR must be installed before it can be used.  The command
   fx_Enable() is used to install FXCOLOR.  None of the commands (except
   fx_IsFxOn() and fx_IsVGA() - see docs for those commands) will perform
   any action and will probably return meaningless values if called while
   FXCOLOR is NOT installed.

   FXCOLOR must be uninstalled before exiting your application.  The
   command fx_Disable() is used to uninstall FXCOLOR.  Although FXCOLOR
   includes detection for program termination and will uninstall itself if
   program termination is detected, this should not be relied upon.  You
   should use the fx_Disable() command.

   When FXCOLOR is installed, it hooks the timer interrupt 1Ch and
   interrupt 21h.  These remain active until uninstalled.  If your
   application uses other intercept routines, you should be sure to nest
   those routines.  An example is below:

        fx_Enable()              <- FXCOLOR timer intercept is installed
           OtherTimer( ON )      <- another timer intercept is installed
           ....                  <- other application code
           OtherTimer( OFF )     <- another timer intercept is uninstalled
        fx_Disable()             <- FXCOLOR timer intercept is uninstalled

   Failure to nest intercept routines will undoubtedly cause you great
   suffering.

   FXCOLOR also disables the hardware blinking bit when installed and
   re-enables it when uninstalled.  When the hardware blinking bit is
   disabled, high-intensity background colors are allowed.  The Clipper
   SetBlink() command performs the same function.  You may use the
   SetBlink() command while FXCOLOR is installed to set hardware blinking
   ON or OFF.  Remember though, if any high-intensity background colors are
   currently displayed, they will revert to normal and the foreground text
   will begin blinking.

   With hardware blinking OFF, if you want to display a high-intensity
   background color, you should use an asterisk "*" instead of a plus-sign
   "+" for the background color in the CLIPPER color string:

        "r/bg*"  <- Ok
        "r/bg+"  <- Does not work

   For FXCOLOR parameters however, you must use the plus-sign "+" to denote
   high-intensity colors:

        fx_Blink( "r", "bg+" )  <- Ok
        fx_Blink( "r", "bg*" )  <- Does not work