[from LISP terminology; `Garbage Collect'] 1. vt. To clean up
and throw away useless things. "I think I'll GC the top of my
desk today." When said of files, this is equivalent to GFR. 2. vt. To recycle, reclaim, or put to
another use. 3. n. An instantiation of the garbage collector
process.
`Garbage collection' is computer-science techspeak for a
particular class of strategies for dynamically but transparently
reallocating computer memory (i.e., without requiring explicit
allocation and deallocation by higher-level software). One such
strategy involves periodically scanning all the data in memory
and determining what is no longer accessible; useless data items
are then discarded so that the memory they occupy can be recycled
and used for another purpose. Implementations of the LISP
language usually use garbage collection.
In jargon, the full phrase is sometimes heard but the abbrev GC is more frequently used because
it is shorter. Note that there is an ambiguity in usage that has
to be resolved by context: "I'm going to garbage-collect my desk"
usually means to clean out the drawers, but it could also mean to
throw away or recycle the desk itself.
Node:GCOS, Next:GECOS, Previous:GC,
Up:= G =
GCOS /jee'kohs/ n.
A quick-and-dirty clone of System/360 DOS that emerged from
GE around 1970; originally called GECOS (the General Electric
Comprehensive Operating System). Later kluged to support
primitive timesharing and transaction processing. After the
buyout of GE's computer division by Honeywell, the name was
changed to General Comprehensive Operating System (GCOS). Other
OS groups at Honeywell began referring to it as `God's Chosen
Operating System', allegedly in reaction to the GCOS crowd's
uninformed and snotty attitude about the superiority of their
product. All this might be of zero interest, except for two
facts: (1) The GCOS people won the political war, and this led in
the orphaning and eventual death of Honeywell Multics, and (2) GECOS/GCOS left one permanent
mark on Unix. Some early Unix systems at Bell Labs used GCOS
machines for print spooling and various other services; the field
added to /etc/passwd to carry GCOS ID information
was called the `GECOS field' and survives today as the
pw_gecos member used for the user's full name and
other human-ID information. GCOS later played a major role in
keeping Honeywell a dismal also-ran in the mainframe market, and
was itself mostly ditched for Unix in the late 1980s when
Honeywell began to retire its aging big
iron designs.