[rescue] Re: [SunRescue] OT: AS/400 stuff

[Ken Hansen]

POSIX is a library of commands and system calls, independednt of the
underlying OS - the idea (way back in the early 80's!) was that the
government would only buy POSIX compliant computers, then if Unisys was
lower cost than a comprable IBM machine, and both has POSIX support, *and*
your programs only used POSIX commands and system calls, then you could
simply re-compile your code on the Unisys and save big bucks.

One problem - POSIX is *extremely* limited functionality, nobody wrote code
to that interface specification only, since it was so limited. See
http://msdn.microsoft.com/library/techart/msdn_posix.htm

A few highlights:

    The POSIX subsystem itself does not directly support printing

    The POSIX.1 specification does not have a requirement for access to
remote file systems

Those would be nice things to have, no?

As far as Unix98 conformance, that is probably an implementation of MKS
tools...

Ken

----- Original Message -----
From: "Joshua D. Boyd" <jdboyd at cs.millersville.edu>
To: <rescue at sunhelp.org>
Sent: Tuesday, June 05, 2001 8:16 PM
Subject: Re: [SunRescue] OT: AS/400 stuff


> What exactly is the difference between Posix and Unix98?  For instance, I
> know that NT comes with a Posix layer, but there is an add-on for NT that
> offers Unix98 certification.  Is it just a bunch of required extra
> programs?  That's what a glance over the unix systems web site seems to
> indicate.