Hive files are the undocumented binary files that Windows uses to store the Windows Registry on disk. Hivex is a library that can read and write to these files. "hivexsh" is a shell you can use to interactively navigate a hive binary file. "hivexregedit" lets you export and merge to the textual regedit format. "hivexml" can be used to convert a hive file to a more useful XML format. In order to get access to the hive files themselves, you can copy them from a Windows machine. They are usually found in %systemroot%\system32\config. For virtual machines we recommend using libguestfs or guestfish to copy out these files. libguestfs also provides a useful high-level tool called "virt-win-reg" which can be used to query specific registry keys in an existing Windows VM. For OCaml bindings, see "ocaml-hivex-devel". For Perl bindings, see "perl-hivex". For Python bindings, see "python-hivex". For Ruby bindings, see "ruby-hivex".