Please read the addendum to the manual below.

When compiling your source code you will want to include FoxGui.h and
FoxGuiPragma.h because they contain the prototypes for FoxGui functions.
It is suggested that you put FoxGui.h and FoxGuiPragma.h into the same
directory and assign FoxInclude: to that directory using a command like

assign FoxInclude: mydir

where mydir is the directory where you put the include files.

Have fun!

   Simon Fox (FoxySoft 08/07/2001).