This page contains material from talks that I have given.

UNIX history

I used to teach various courses on UNIX, from a short intensive one up to a full length module. At the start, I gave about 90 minutes (for historical reasons, often split into two 45 minute chunks) on the history of UNIX. I don't pretend that it's complete (and it has some simplifications and possible inaccuracies), but I think it gives some useful background and can inspire people to find out more.

As it happens, that particular talk has its own page, which you can find at http://unixhistory.tavi.co.uk . It includes the slides and a recording of the lecture. There is also a one hour lecture on using UNIX, which is mainly about the underlying philosophy; this was intended as a precursor to five one-hour interactive sessions.

The UNIX Shell

This is a selection of some lectures I gave about the UNIX shell, and about shell programming. It isn't all that detailed, but it's a good starting point. It reads a bit like a reference document, because I didn't expect anyone to buy a book.

There are four lectures; read them in order. Two things to remember:

• The notes areas for the slides sometimes have something useful in them.
• View the slides as a presentation (i.e. using F5) so that you experience the animation on some of them.

Here are the slides:

1. Using UNIX
2. More about the Shell
3. Even more about the Shell
4. Shell Scripting

Emulation and Other Stories

This is a talk I gave to the BCS Kent Branch in December 2019. It's about the various ways in which one can play with the way that old hardware worked. I put it here because it was not possible to host it on the BCS website in an acceptable format, and in any case it is of more general interest. Once again, it consists of the slides, but no recording this time.

• The complete set of slides can be found here.
• I also added some audio (basically, the content of the talk) and turned it into a video, which you can find here.
• The PiDP website (where you can order a kit) is at: https://obsolescence.wixsite.com/obsolescence.
• Lots of ancient documentation is preserved at: http://www.bitsavers.org.

I gave an abbreviated versin of this talk to Codeharbour in May 2023.

In the talk, I also mentioned that I was looking at doing an emulated panel for the Honeywell DDP-516. There is an anecdote about my experience with the DDP-516 (when I was an undergraduate) here.

There is a story about my research for details of the panel here.

Telephone Systems and Voice over IP

This is a talk I gave to the BCS Kent Branch in December 2018. It's essentially about the development of my home telephone system, from a simple phone line to a fully functional Voice over IP system, with some interesting capabilities. Once again, it consists of the slides, but no recording.

• The complete set of slides can be found here.
• I also added some audio (basically, the content of the talk) and turned it into a video, which you can find here.