[HECnet] RSTS/E started emitting "?EVTLOG (BLDNIC) -- %Integer error" messages

Thomas DeBellis tommytimesharing at gmail.com
Fri Nov 12 12:48:52 PST 2021


This reminds me of some Tops-20 code that does vaguely analogous on a 
power fail.  It flushes a lot of stuff to files and the page store, 
waits for the disks to settle down and then signals the 11.

On a re-power, it comes back up near to where it was and (supposedly) 
continues.  However, not everything is read back to memory.  I would 
imagine that the code has to date back to TENEX days and core memory, 
where the image would persist.

I have wanted to experiment with it by having KLH-10 catch a SIGPWR and 
appropriately signaling and then saving the memory. The functionality 
could be useful for a KLH10 on a laptop that was put to sleep.

On 11/12/21 1:06 PM, Paul Koning wrote:
>
>> On Nov 12, 2021, at 10:57 AM, Johnny Billquist <bqt at softjar.se> wrote:
>>
>> On 2021-11-12 15:24, Paul Koning wrote:
>>>> On Nov 11, 2021, at 6:22 PM, Johnny Billquist <bqt at softjar.se> wrote:
>>>>
>>>> I must admit that I hadn't considered the possibility of just saving the core. Which of course can accomplish the same thing in a neat way.
>>> That's a bit like how RSX-11/D and IAS boot -- by reloading the image of memory when you issued the SAV command.  Pretty clever: you set things up the way you want them to be, and then you make that state persistent.
>> Same with -11M. But it's only used for the kernel.
>>
>> However, in TOPS-20 as well as some other DEC OSes, this is a common pattern for all programs.
> In the sense that an executable program is basically a memory image?  Yes, RT-11 SAV files are a good example.
>
> But the RSX-11/D and IAS case is a whole-system image, not kernel or a single program.  You boot the OS, load all the applications you want to be active in their various partitions, and type SAV.  When the system boots, that whole memory image is loaded, and made active by delivering power-fail ASTs to each task.  For example, SAV also handles the boot-time setup, for example prompting for the current date and time.  (Or perhaps it doesn't do that in the stock version; I remember adding it to SAV in 1978, as part of Typeset-11 work.)
>
> 	paul
>
>


More information about the Hecnet-list mailing list