Can anyone comment on IBM Xenix v2.0?

[Bill Vermillion]

In article <FZ+AP5 at xds13.ferranti.com> peter at ficc.ferranti.com (Peter da Silva) writes:
>In article <1991Apr26.001231.4238 at bilver.uucp> bill at bilver.uucp (Bill Vermillion) writes:

>> The only other thing that ever go me as bad was working on an old Z8000
.....
>> Believe the machine was an Onyx if memory serves.
   
>> This one would sign extend all the odd (or perhaps it was even) characters
>> from a 7bit to 16 bits with the high bit set.   So every other character in
>> the set was a negative number

>But that's what it was supposed to do. If you're working with signed characters
>(default on many machines, including the Z8000 and 80x86!) and converting
>them to integers then it's suposed to sign extend.

On that one the code that worked on the 80386 did NOT work on the Z8000.

I also had the c_iflag set with ISTRIP to stip all incoming chars to 7
bits.   The compiler on the Z8000 wouldn't, but the one on the 80386 would.
    
I had other people look at it too, and it was only when we started
monitoring the bit stream we found it.

>
>Program the following sequence in your wetware:
>
>	i = (((int) c) & 0xFF);
>
>It's a lot of work to write portable (as opposed to ported) code, but it's
>worth it. For one thing all sorts of "bugs" in the O/S tend to vanish.

True.  I will remember that.   That line is about what I ended up with.
The problem arose when the "serial device" program was being written on the
80386 machine, and then the code wouldn't run when ported to the other.

The way I read the manual, ISTRIP should have returned a 7bit that should
not have 8th bit set.  But when 8th bit was set, so would bits 9 thru 16.
If c_iflag has ISTRIP set, and it passed the 8th bit wouldn't you consider
that a compiler bug.?

-- 
Bill Vermillion - UUCP: uunet!tarpit!bilver!bill
                      : bill at bilver.UUCP