have you copied factorial.c and factorial.h into the directory created by h2xs?

It seems that h2xs is not able to generate the XS declarations for the functions in factorial.c

That's what it produces in my machine: 

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "ppport.h"


MODULE = Book::Factorial        PACKAGE = Book::Factorial

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In reply to Re: own perl module based on c library by salva
in thread own perl module based on c library by gants

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