On Thu, Oct 8, 2015 at 7:43 AM, <rob@xxxxxxxxx> wrote:
I think the difference [between Qshell and PASE] is that
one follows certain open system standards closely. The
other one is more likely to work with many of the examples
you find on the internet.
You don't say which is which, but I don't agree with either of them.
Well, I don't agree with the implication that only one of them is
standards-based, and I don't agree with the notion that the one which
is "not-standards-based" would somehow be MORE likely to work with
examples from the Internet. Wouldn't standards-based examples be more
common on the Internet?
The IBM "marketing gibberish" is that Qshell is "based on POSIX and
X/Open standards". It's a true statement, but it's also not very
informative. The whole point of those standards was actually to
establish a common ground for the various Unix implementations. So if
you follow the other IBM marketing gibberish, which is that PASE *is*
AIX, and that AIX *is* a Unix, then by definition, PASE *is* a Unix,
and thus should be at least as POSIX- and X/Open-comforming as
anything else that runs on the i. The gibberish in this case is the
"PASE is AIX" part. It's not, really. As Buck expressed it recently,
it's an amorphous subset of AIX. But there is widespread agreement
that (1) it's the closest thing to Unix on the i, and (2) AIX really
and truly is a Unix.
Actually, the real, substantive difference between Qshell and PASE is
more fundamental. They're different beasts entirely. Qshell is a
command shell, intended for interactive use or scripts. It's like the
CL interpreter you usually get at a ===> prompt, except that instead
of "IBM-mainframe-like" commands, you get Unix-like commands.
PASE is actually much, much more than that. It's a whole "runtime
environment". It's designed to allow programs which are compiled for
AIX to run as-is on the i. That is, if I compile a C program on a
genuine AIX machine, I should (in principle) be able to copy the
resulting binary executable object over to the IFS and just run it in
As usual, Scott explained it quite well:
I think you start pase with
Er, sort of. You don't need QP2TERM to "start" PASE, but QP2TERM is
one way to interact with PASE. It opens a command shell that runs in
PASE. In contrast, QSH starts a Qshell session which runs in the
native i ILE environment.
From an interactive point of view, both QSH and QP2TERM provide a
Unix-like command experience. QP2TERM is inherently ASCII-based (as
AIX is inherently ASCII-based) while QSH is EBCDIC-based.