[TUHS] Early Unix Spider network

Paul Ruizendaal pnr at planet.nl
Fri May 26 05:31:03 AEST 2017


>> It is a paper copy, but I can make a scan for you.
> 
> That makes it sounds like it might not be possible to put it online?
> What's the exact title, so I can look and see if it's already online?
> I'm pretty sure I've got a hardcopy of some Spider thing, but it would
> probably take me a while to find it... ;-)

The report I have is:
"SPIDER-a data communication experiment", Tech Report 23 , Bell Lab, 1974.
I did not find it online, but it may be out there somewhere.

I think it can be public now, but doing some checks.

> OK, the only one I have is 'nfs'. Here's the source, and man page:
> 
>  http://ana-3.lcs.mit.edu/~jnc/tech/unix/s2/nfs.a
>  http://ana-3.lcs.mit.edu/~jnc/tech/unix/man6/nfs.6

Many thanks! There is some puzzling stuff in there that I'd like to
figure out, but that is easier to discuss once the report is online.

Also, it turns out that the TIU driver was in Warren's repo all along:
http://minnie.tuhs.org/cgi-bin/utree.pl?file=V4/nsys/dmr/tdir/tiu.c
http://minnie.tuhs.org/cgi-bin/utree.pl?file=V4/man/man4/tiu.4
It's fun to read that the V4 man page says "The precise nature of the
UNIX interface has not been defined yet." and Noel's version says:
"The precise nature of the UNIX interface is defined elsewhere." (yet
the dates are the same!).

Some things are surprising (to me, at least):

First of all, opening a connection to the File Store is a single open on
data channel 1:
http://chiselapp.com/user/pnr/repository/Spider/artifact/854a591c0e7a3a54?ln=26
I would expected the code to first have sent a connection request to the
switch on control channel 1. Perhaps the File Store was an integral part
of the switch/router (a Tempo minicomputer 
ftp://bitsavers.informatik.uni-stuttgart.de/pdf/tempoComputers/TEMPO-1_ad_Nov69.pdf)
with channel 1 functionality hardwired.

Next, the code has a hackish form of non-blocking I/O:
http://chiselapp.com/user/pnr/repository/Spider/artifact/55ee75831bd98d6c?ln=35,37
I'm puzzled about the alarm() sys call. That did not exist in 1973 -- or did it
only exist in Bell Labs private builds?

The code calls snstat(), for instance here:
http://chiselapp.com/user/pnr/repository/Spider/artifact/55ee75831bd98d6c?ln=38
That seems to be a sys call to here:
http://chiselapp.com/user/pnr/repository/Spider/artifact/2c7d65073a7cb0a5?ln=474,524
Could that be the tiu sys call (#45) in the sysent.c table for V4-V6?











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