PDP 11/23 running UNIX version 6 at VCF Midwest! @DrDavesDiversions

Dr. Daves Diversions | PDP 11/23 running UNIX version 6 at VCF Midwest! @DrDavesDiversions | Uploaded September 2021 | Updated October 2024, 3 hours ago.
In this video I share my personal pick for "best" demo at VCF Midwest: Gavin's PDP 11/23 running UNIX Version 6! We write and run a simple BASIC program in Ken Thompson's bas(1), finding some quirks with this (currently) entirely floppy-based system, possible having to do with a glitch in disk I/O. (We discovered bas(1) uses a temporary file as backing store.)

Filmed at the Vintage Computer Festival Midwest: VCF Midwest 16, September 11, 2021
vcfmw.org

Here's the source code to the simple program we wrote; you can also run it on modern machines if you install a Research UNIX version using SimH (pdp-11 simulator).

5 goto 30
10 for col = 1 arg(1)
12 prompt " "
14 next
20 print "Welcome to VCF Midwest!"
25 return
30 for x = 0 55
40 10(x)
50 next
60 for x = _56 _1
70 10(_x)
80 next

Related:

bas man page (v7 UNIX)
unix.com/man-page/v7/1/bas

"No BS: the First UNIX BASIC!"
youtube.com/watch?v=LZUMNZTUJos

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