$ h2xs -n Book::Factorial -A -O -x -F factorial.h
Defaulting to backwards compatibility with perl 5.10.1
If you intend this module to be compatible with earlier perl versions, please
specify a minimum perl version with the -b option.

Writing Book-Factorial/ppport.h
Scanning typemaps...
 Scanning /usr/local/perl/5.10.1/lib/5.10.1/ExtUtils/typemap
Writing Book-Factorial/lib/Book/Factorial.pm
Writing Book-Factorial/Factorial.xs
Writing Book-Factorial/Makefile.PL
Writing Book-Factorial/README
Writing Book-Factorial/t/Book-Factorial.t
Writing Book-Factorial/Changes
Writing Book-Factorial/MANIFEST

----

$ h2xs -n Book::Factorial -A -O -x factorial.h
Defaulting to backwards compatibility with perl 5.10.1
If you intend this module to be compatible with earlier perl versions, please
specify a minimum perl version with the -b option.

Writing Book-Factorial/ppport.h
Scanning typemaps...
 Scanning /usr/local/perl/5.10.1/lib/5.10.1/ExtUtils/typemap
Scanning factorial.h for functions...        # <--- !!
Scanning factorial.h for typedefs...
Writing Book-Factorial/lib/Book/Factorial.pm
Writing Book-Factorial/Factorial.xs
Writing Book-Factorial/Makefile.PL
Writing Book-Factorial/README
Writing Book-Factorial/t/Book-Factorial.t
Writing Book-Factorial/Changes
Writing Book-Factorial/MANIFEST

##</code><code>##

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

#include "ppport.h"

#include <factorial.h>


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


double
factorial_iterative_c(x)
	int	x

double
factorial_recursive_c(x)
	int	x