how to general a db creation script from an exiting db?

alter database backup controlfile to trace; the info from the controlfile seems not enough, any other way to generate scripts like:

create database
...

create rollback segment
...

alter rollback segment r0 online;
...

create tablespace temp datafile
...

create tablespace tools datafile
...

create tablespace users datafile
... Received on Wed Aug 28 2002 - 12:16:39 CEST