So, I came across this tape: http://bitsavers.trailing-edge.com/bits/DEC/pdp11/dectape/ TU_DECtapes/unix6.dta I was curious what was on it, so I read the description at: http://bitsavers.trailing-edge.com/bits/DEC/pdp11/dectape/TU_DECtapes.txt UNIX1 PURDUE UNIX TAPES UNIX2 UNIX4 UNIX6 HARBA1 HARVARD BASIC TAPE 1 HARBA2 HARVARD BASIC TAPE 2 MEGTEK MEGATEK UNIX DRIVER RAMTEK RAMTEK UNIX DRIVER Cool, sounds interesting, so I downloaded the unix6.dta file and fired up simh - after some fiddling, I figured out that I could get a boot prompt (is that actually from the tape?) if I: set cpu 11/40 set en tc att tc0 unix6.dta boot tc0 = At that point, I was stuck - the usual tmrk, htrk, and the logical corollary tcrk didn't do anything except return me to the boot prompt. I was thinking this was a sixth edition install tape of some sort, but if it is, I'm not able to figure it out. I thought I would load the tape into v7 and look at its content using tm or tp, but then I realized that I didn't have a device set up for TU56 and even if I did, I didn't know how to do a dir on a tape - yeah, I know, I will go read the manual(s) in chagrin. In the meantime, my question for y'all is similar to my other recent questions, and it goes like this: When you received an unmarked tape back in the day, how did you go about figuring out what was on it? What was your process (open the box, know by looking at it that it was an x rather than a y, load it into the tape reader and read some bytes off it and know that it was a z, use unix to read the tape using tm, tp, tar, dd, cpio or what, and so on)? What advice would you give a future archivist to help them quickly classify bit copies of tapes :). Thanks, Will -- GPG Fingerprint: 68F4 B3BD 1730 555A 4462 7D45 3EAA 5B6D A982 BAAF

A quick look, and I think it's an stp (super TP) tape -- stp is from the Harvard distribution.   This would make sense, because that was the standard back before tar. As Ron pointed out, tp (which Ken designed for DECTapes originally) puts the index at the head of the tape (tar and later cpis threaded the index inline).   But it means its a fixed size and there were some other issues (tp may have originally been in assembler IIRC).   On DECtape, tp worked pretty well/was pretty cool because you could update a block, less so on 9-track which when you re-wrote block N, you lost all blocks afterwards.  Also, I don't remember why now [probably the limits off the directory], but it was typically in those days to take all the files in a directory, turn them into a foo.a (ar format) archive.  So the stp image was a bunch of files: dir1/mumble.a  dir2/grumble.a dir3/bumble.a ... You then needed to unarchive the files within each directory.   Also, remember ar(1) when through some changes in format between 4-7th editions as the compiler and linker matured.  So watch out on that front too... Anyway, v6 tp probably will read it, but if you poke around the TUHS and bitkeeper archives for the original Harvard distribution, stp.c should exist.

I'll look around. v6 tp was able to read the tape: set tc en att tc0 unix6.dat c # chdir /usr/6 # tp t0 speakez/sbrk.s dcheck.c ... the directories don't get created on extract, but that's typical on v6.

If you LISTREVERSE’ed a Lisp program, it would look like PostScript with parens! I have been wondering about that for years. Here’s the manual! LISTREVERSE is documented on page 9-3. Maybe if I printed out the "READERS COMMENTS" form at the back of the manual, wrote my question in big upper case block letters, then ticked the "If you require a written reply, please check here” checkbox, then “Fold Here” and “Do Not Tear - Fold Here and Staple” as instructed, I could mail in the free first class pre-addressed, business reply mail, no postage stamp necessary if mailed inside the United States envelope, and they’d write me back a nice letter telling me what the fuck they were thinking. http://bitsavers.informatik.uni-stuttgart.de/www.computer.museum.uq.edu.au/… -Don

On 19 Nov 2017, at 01:35, Steve Nickolas <usotsuki(a)buric.co> wrote: On Sat, 18 Nov 2017, Arthur Krewat wrote: Can't speak for DEC's dialect. Apple's dialect supported LIST start,end and Microsoft's dialects supported LIST start-end (with some supporting the comma variant as well). Never heard of a backward LIST before. o.O -uso.

List start,end Is standard Dartmouth basic from Kemeny & Kurtz - (aka K&K) which was the equivalent of K&R in those days. [i think I have my Dad’s copy from they early 1960’s - which is what he taught me with in 1967]. And Yes DEC basic supported it Sent from my PDP-7 Running UNIX V0 expect things to be almost but not quite.