access of global variables from modules

[Mr. Peter Ivanyi]

Hello again,

I have another problem with modules.
If I have a module can the module access "global" variables.
I have an application, which defines some global variables. 
The application also loads some modules and I would like to access
the global variables from the module. 
How can I do it ? (I think I can put the global variables into a module
and another module can depend on it, but isn't there another way ?)

For example I have this module (gen.scm):
----------------------
(define-module (gen gen))
(export gen-hello)

(define (gen-hello)
  (set! *G* 3)
  (display "Hello World !")
  (newline)
)
-------------------------

then I receive this

-------------------------
address@hidden $ guile
guile> (define *G* 1)
guile> (use-modules (gen gen))
guile> (gen-hello)
./gen/gen.scm:7:1: In expression (set! *G* 3):
./gen/gen.scm:7:1: Unbound variable: *G*
ABORT: (unbound-variable)

Type "(backtrace)" to get more information or "(debug)" to enter the debugger.
guile> 
-------------------------

instead of setting *G* to 3 and then print "Hello World !".

Thanks, for your help in advance.

                                        Peter Ivanyi