Glossary - H

Glossary of Multics acronyms and terms. Entries by Tom Van Vleck ([THVV]) unless noted.

hardcore

[BSG] (1) That portion of the Multics that is loaded from the boot tape and runs in ring 0; the supervisor, the operating system kernel. The common phrase "hardcore supervisor" (hcs) is essentially redundant.

[THVV] (2) The system programmers that built the hardcore, especially used in reference to social activities. Story: "Low Bottle Pressure".

hardcore partition

Partition, on the RPV, used for the pages of the segments that constitute the pageable portion of the supervisor, not actually part of the user-visible file system. See deciduous.

hardware monitor

See yellow submarine.

HASP

Houston Automatic Spooling Program. An IBM Type II program that managed input and output queues and RJE for big 360s. Multics had some software to talk to HASP, pretending to be an IBM 2780 (reader/punch device), over a bisync line.

hcs_

Gate into the hardcore supervisor. Most Multics supervisor functions available to ordinary programs are provided as entrypoints in this segment, for example the file system (hcs_$initiate). Other gates are phcs_ and hphcs_.

HEALS

Honeywell Error Analysis and Logging System. This subsystem reads the hardcore error log and can suggest maintenance procedures to a field engineer before a device fails.

help

The first Multics help facility simply printed out system "info segments" with pauses. Over time this code became more and more elaborate. Similar to the Unix man pages, but many of the info segs that the help command references are automatically extracted from the runoff source of the Multics commands manuals. source online Info segment for help command

hierarchy

The Multics file system names files (segments) with multi-part names separated by > and organized into a tree-structured hierarchy. Unlike files in the Unix file system, a Multics segment or directory is a child of only one parent.

HISCAN

Honeywell Information Systems, Canada. A marketing organization.

HISLTD

Honeywell Information Systems, Limited. Marketing organization for the UK.

HISUK

Another name for HISLTD.

HLR

Multics site. Hoffman-LaRoche Pharmaceuticals, Nutley NJ, USA. Installed 1982.

[Michael Ronayne] HLR was a big Honeywell GCOS shop and the Multics system was purchased to supplement the research efforts and provide better TSS than was available through GCOS. There was never a benchmark for Multics as we were very conversant with the product. Roche had already begun making some small moves to IBM, but with the death of Multics and big layoffs at Roche, Honeywell was finished at Roche.

HLSUA

Honeywell Large Systems Users Association. Pronounced "h'lashua". Also, colloquially, a reference to the twice-yearly users' meetings held by this organization. (Similar to SHARE but much smaller.)

[Logan Lewis] Having served on the staff of HLSUA, I believe it would be better pronounced as "hel' shu a".

home directory

Each user on a project has a home directory, inferior to the project directory, where per-user segments such as start_up.ec are stored.

Honeywell

USA conglomerate. Manufactured thermostats, anti-personnel cluster bombs, control systems, aircraft avionics, and, for a while, computers. Bought GE's computer division in 1970, including CISL and the Multics project. Sold the computer business to Bull in 1987. Story: Honeywell Management

HOPL

History of Programming Languages. ACM conference.

hphcs_

[BSG] Highly Privileged HardCore Supervisor, pronounced "h'putschkiss", after Greenberg. A gate that allows arbitrary patching of the supervisor, bringing the system down, and control of critical parameters. Access to this gate is controlled by an ACL, like access to all segments in Multics. Although someone who "has hphcs_" has "super powers", the difference between this and a Unix super-user is significant -- access to the facilities in hphcs_ does not disable the file system's access control.

HRX

Internal Honeywell codename for the DPS6plus.