IO-Lite: 1998/1999
     - uses immutable/read-only blocks of data
     - assembles user data out of these blocks
       via "buffer aggregates" which are
       mainly ordered lists of <pointer,len> pairs
       to the read-only buffers.
     - uses an own user-land API dealing
       with buffer aggregates instead of
       continous buffers
     - required kernel support (wants to
       do page-remapping and copy-on-write)
       for really optimized I/O
     => not directly useable for user-land I/O lib
        wegen den Kernel-basierten Optis, aber die Idee der buffer aggregates
        kann interessant sein.