Reply to post: Re: Ah the good old days

Beware the trainee with time on his hands and an Acorn manual on his desk

Peter Gathercole Silver badge

Re: Ah the good old days

* represeented an OS or sideways ROM command, not just Econet.

Basically, when the CLI parser saw a line starting with a *, it offered it to each sideways ROM in the system in the order of priority (I think it went from 15 down to 0), and if none of the sideways ROMs claimed the command, the OS checked against itself, and then looked at the currently active filesystem to see whether there was a command that matched in the current directory.

Econet was implemented as just another sideways ROM, and also provided a filesystem type.

Acorn did a really excellent job of designing the BBC Micro operating system, something it started in the System 2 and Atom days, and continued on into Arthur and RiscOS on the Archimedes and RiscPC.

The only real problem with the BBC and Econet is that it was completely impossible to secure the network.

There was the concept of a privileged workstation that had higher capabilities than the rest of the network. It was identified as having a station number of 0 (the station number was set either by soldering links on a location on the keyboard or fitting an 8 switch DIL switch in the same location (we used to call them DIP switches, can't remember why). This was read into a memory location when the BEEB was turned on, but unfortunately, the BEEB having no protected hardware, allowed the station number to be overwritten by whoever was on the system. This gave anybody the capability of becoming station 0.

There was a similar byte that could be overwritten with the current user ID, which identified you to the network, allowing you to masquerade as anybody on the network!

So Econet was good in principal, but unfortunately not so good in practice.

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