> From: Random832
> Not quite. On a stock V6 kernel, system call 30 (smdate/utime) maps to
> nullsys rather than nosys.
Oh, right. (Hadn't checked the number, assumed they used a new one for utime.)
Noel
> From: Random832
> Non-existent syscalls map to nosys, which sets u_error to 100 ... which
> causes the process to be sent a signal SIGSYS.
Oh, right, I'd forgotten that.
So, getting back to v6tar, I'll bet that if you try and use it to _read_ a TAR
file file under V6 (i.e. write files into the V6 filesystem), it will bomb out
(because of the call to utime).
Noel
> From: Mark Longridge
> Not too sure about reversing getpid.o, but maybe possible with db?
Well, me, I'd just use 'od' - but then again, I have ucode for disassembling
PDP-11 octal! :-) (OK, OK, so a lot of the less common instructions I have
to look up! :-)
But, seriously, yeah, 'db' is probably the way to go.
FWIW, it's possible to get 'adb' running under V6 without much (any?) work,
too. Although maybe it needs the 'phototypesetter' C compiler? I'd have to
check...
There's also a 'cdb' running around (I found a copy on the 'Shoppa disks'),
which is basically 'db' but augmented with a few useful commands - maybe stack
backtrace, I don't recall the details, the documentation in on my V6, and I
don't feel like spinning it up just to look for that.
Noel
So, speaking of system calls that are missing in earlier versions of Unix,
that tickled a memory:
> From: Will Senn
> ... a special version of tar must be prepared to run on V6.
> The document goes on to describe a reasonable method to make v6tar on
> v7 and copy the binary over to the v6 system.
When I got tar running on my V6, I didn't know about this, and I took
a V7 tar and got it running myself, see here:
http://mercury.lcs.mit.edu/~jnc/tech/ImprovingV6.html#tar
One thing I found out while doing that is that tar uses the 'utime' system
call on V7 to set the file date, but i) V6 doesn't have utime() (although it
has smdate(), albeit commented out in the standard distro), and ii) on now
looking in src/cmd/tar and src/libc/v6 in the V7 distro, I don't see a
replacement version of utime().
As near as I can make out, 'v6tar' must be using the standard V7 version of
utime(), which I assume turns into a call to nosys() on V6 (returns an error);
tar doesn't check the return value, so the call fails (silently). So v6tar
won't correctly set the file date when moving a file _to_ V6.
Noel
> From: Mark Longridge <cubexyz(a)gmail.com>
> if one looks at /lib/libc.a via 'ar t getpid.o' you can see the object
> file getpid.o
Library, schlibrary! The important question is 'is it in the kernel source'?
(Although now that I think about it, if the library routine tries to use a
non-existent system call, it should return an error. It would be interested
to disassemble the library routine, and see what it thinks it is doing.)
Noel
On 2015-12-12 06:31, Peter Jeremy<peter(a)rulingia.com> wrote:
> Also, I've seen suggestions that there's a 2.11BSD patch later than
> 447 but I can't find anything "official" andwww.2bsd.com is either
> down or inaccessible from all the systems I have access to. Does
> anyone know if 448 or later were released? And given the issues with
> www.2bsd.com would someone be willing to mirror it (assuming we can
> got a copy of it)?
Yes, I did 448. Various bits and pieces that were fixed there, but
unfortunately I haven't managed to reach Steve to get it officially
sanctioned.
I've passed it out a few times, but there is no canonical place for it.
You can find it at ftp://ftp.update.uu.se/pub/pdp11/2.11bsd/
Feel free to pass that information around.
Things fixed in there:
. Added a timeout to boot prompt for automatic boot
. Made console 8-bit clean
. Changed gethnamadr to fall back to /etc/hosts if dns fails.
. Fixed kernel build process to get version and date properly into kernel.
. Fixed raboot to work on non-DEC mscp controllers
. Fixed tmac macro to work correctly after 2009.
. Fixed a couple of documentation errors.
Essentially small issues that bothered me as I was running on an 11/84
with a CMD controller a few years ago. A system on which I also booted
other OSes, which is why the 8-bit clean issue also bothered me.
(Also was really surprised at the ugly Y2K fix someone had done with
tmac, which failed again in 2010).
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt(a)softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
Ken Iverson was born in 1920; he is (in)famous for inventing APL. And if
you haven't used APL\360 on a dumb Kleinschmidt[*] terminal, you didn't
miss anything.
[*]
And that's the first time I've seen a spell-checker suggest that it be
replaced with "Consummated".
--
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."
Some time ago, someone posted an early Unix image that I recall
running. I know it was pre-groups but don't recall anything else and
I can't find either the images or mailing list references either
locally or on tuhs.org. Does anyone recall the details.
Also, I've seen suggestions that there's a 2.11BSD patch later than
447 but I can't find anything "official" and www.2bsd.com is either
down or inaccessible from all the systems I have access to. Does
anyone know if 448 or later were released? And given the issues with
www.2bsd.com would someone be willing to mirror it (assuming we can
got a copy of it)?
--
Peter Jeremy
> I got it.
Ta muchly! All seems OK now, after TUHS moved to a new ISP (linode,
which, ahem, is known for hosting spammers).
--
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."
1 2 3... Is this mic on? Tap tap...
Seriously, my anti-spam defences were having an issue with this list for a
while, so let's see whether it comes back.
--
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."
