Christian Lheureux <[log in to unmask]> wrote:

>  > The fact that MPE/iX is aware of Image also
>>  helps.  HP-UX has
>>  no idea what a database is.
>
>Neither has MPE. XM is an MPE feature that ensures MPE data integrity. The
>fact that it includes TurboImage is a coincidence. And, may I say, a very
>fortunate one.


I got a private message with this comment:

       I was always under the impression that MPE (even MPE-V)
       treated Image files and intrinsics as special.


Here are some comments from my bits-and-bytes perspective:

MPE (even MPE-V) has a very rich file system (which, if people
involved with other OSs took the time to study, would benefit
by copying MPE's ideas into their pet OSs :-)

IMAGE just happens to take full advantage of such a wonderful
file system.

The fact that all IMAGE files are *privileged* files certainly
provides a good basis for perceiving that MPE treats IMAGE files
as "special", because privileged files are, by definition,
"special".  But privileged files are just one "category" or
"type" or "class" of MPE files.  The MPE file system has many
other powerful features.

Come to think of it, there is nothing truly "special" about
privileged files (ANY file can be made privileged by simply
changing its file code to a negative number -- but this requires
PM capability and, so, is not a trivial matter for the casual
hacker :-)

The beauty of the "privileged file" concept is that only privileged
processes can "open and access" such files and it is up to
the system manager to decide WHICH processes (and which accounts
and which groups and which users) have PM ("privileged mode")
capability and which do not.

I don't want to bore everyone by waxing poetic about MPE's file
system.  Hopefully, this little discussion on ONE aspect (the
"privileged" category) will give you a taste.

So, both Christian and John are correct.  MPE (and HP-UX and
Linux and MS Windows and Mac OS) may or may not have any idea(s)
regarding databases.  MPE just happens to provide a much richer
file infrastructure that good database designers (take Fred White
as an example) can exploit to its fullest advantage.

Now, on to a tough challenge:  How did the topic "HP Press Release
about hp3000" change into "MPE's rich file system"?  I wish that
*all* marketing topics would evolve into technical topics :-)

   _______________
  |               |
  |               |
  |            r  |  Alfredo                     [log in to unmask]
  |          e    |                           http://www.adager.com
  |        g      |  F. Alfredo Rego
  |      a        |  Manager, R & D Labs
  |    d          |  Adager Corporation
  |  A            |  Sun Valley, Idaho 83353-3000            U.S.A.
  |               |
  |_______________|

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