Updating: preparing book/ATS2TUTORIAL.
Updating: minor addition.
Updating: minor addition.
Updating: very minor.
Updating: adding some testing code.
Updating: adding libc/fcntl.
Updating: adding some testing code.
Updating: improving ATS2TUTORIAL.
Updating: improving prelude/arrayptr.
Updating: improving prelude/arrayptr.
Updating: improving ATS2TUTORIAL.
Updating: improving prelude/integer.
Updating: improving prelude/integer
Updating: minor addition.
Updating: adding some testing code.
merge