From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave@horsfall.org (Dave Horsfall) Date: Mon, 28 Mar 2016 06:59:43 +1100 (EST) Subject: [TUHS] PDP-11/70 SPL (was: Early non-Unix filesystems?) In-Reply-To: <56F7B06F.6040005@update.uu.se> References: <56F7B06F.6040005@update.uu.se> Message-ID: On Sun, 27 Mar 2016, Johnny Billquist wrote: > I do not have any experience either way. I have never checked this. I'm > just saying that it don't make sense in my head, and the processor > handbook do not describe such a property of SPL. But now that I know, > I'm going to try and find out. I'll say it again: it's *definitely* how SPL worked (at least, on the 11/70 that I hung; too many witnesses...). Somewhere Out There (tm) is a little self-relocating program that completely filled user memory with SPL (including overwriting itself; the last act it did was to overwrite itself, and was sheer genius). I saw it in a ;login: newsletter, so it *might* be in AUUGN... When the PC wrapped around, it was SPLs all the way down :-) > It would also be interesting if anyone can come up with a good reason > why SPL should work that way. Likely a firmware bug? -- Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."