[TUHS] Abstractions

[Wesley Parish]

I've just checked Slackware 14.* and it's still got a few binaries in
/bin, unlike the RedHat* group which has indeed sent them all to
/usr/bin. I don't know about the Debian* group, or if the Mandrake*
group have gone with the RedHat* or not. Let alone all the other
distros.

Wesley Parish

On 2/22/21, Dave Horsfall <dave at horsfall.org> wrote:
> On Sat, 20 Feb 2021, M Douglas McIlroy wrote:
>
>>>  - separation of code and data using read-only and read/write file
>>>  systems
>>
>> I'll bite. How do you install code in a read-only file system? And where
>> does a.out go?
>
> I once worked for a place who reckoned that /bin and /lib etc ought to be
> in an EEPROM; I reckon that he was right (Penguin/OS dumps everything
> under /usr/bin, for example).
>
>> My guess is that /bin is in a file system of its own. Executables from
>> /letc and /lib are probably there too. On the other hand, I guess users'
>> personal code is still read/write.
>
> That's how we ran our RK-05 11/40s since Ed 5...  Good fun writing a DJ-11
> driver from the DH-11 source; even more fun when I wrote a UT-200 driver
> from the manual alone (I'm sure that "ei.c" is Out There Somewhere),
> junking IanJ's driver.
>
> The war stories that I could tell...
>
>> I agree that such an arrangement is prudent. I don't see a way, though,
>> to update bin without disrupting most running programs.
>
> Change is inevitable; the trick is to minimise the disruption.
>
> -- Dave, who carried RK-05s all over the UNSW campus
>