12 Aug
2015
12 Aug
'15
6:41 p.m.
On Aug 12, 2015, at 1:39 PM, Nigel Williams <nw at
retrocomputingtasmania.com> wrote:
That sounds right. For one thing, it is clear if you study the hardware manuals that the
system is NOT secure against machine language programmers. Security comes from the fact
that the compilers other than ESPOL will not generate code that compromises security, and
the ESPOL compiler is protected so that ordinary peons do not have access to it.
I found this out when I tried to write a program that reads foreign format tapes, in
particular past tape marks. Algol can?t do that ? either that, or the consultants
couldn?t figure out how. I started looking at other languages, but when I started asking
questions about DCALGOL I got a whole lot of pushback from the system staff. They viewed
questions like that with extreme suspicion.
paul
On 12 Aug 2015, at 11:24 pm, Paul Koning
<paulkoning at comcast.net> wrote:
...
Did Algol come after the hardware? I always thought of the hardware as having been
customized for their Algol, but admittedly I don?t actually know which is chicken and
which is egg.
It is suggested in the oral history at UMN.edu that the B5000 was designed as an ALGOL
machine and Burroughs had the idea that only compilers would generate machine code, so
they made the B5000 compiler friendly, and the system would have an OS to manage
resources, so it was designed around drum/disk being an intrinsic part of the system.