heisenbug /hi:'zen-buhg/ n.
[from Heisenberg's Uncertainty Principle in quantum physics] A
bug that disappears or alters its behavior when one attempts to
probe or isolate it. (This usage is not even particularly
fanciful; the use of a debugger sometimes alters a program's
operating environment significantly enough that buggy code, such
as that which relies on the values of uninitialized memory,
behaves quite differently.) Antonym of Bohr bug; see also mandelbug, schroedinbug. In C, nine out of ten
heisenbugs result from uninitialized auto variables, fandango on core phenomena (esp.
lossage related to corruption of the malloc arena) or errors that smash the stack.
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Helen Keller mode n.
1. State of a hardware or software system that is deaf, dumb,
and blind, i.e., accepting no input and generating no output,
usually due to an infinite loop or some other excursion into
deep space. (Unfair to the
real Helen Keller, whose success at learning speech was
triumphant.) See also go
flatline, catatonic. 2.
On IBM PCs under DOS, refers to a specific failure mode in which
a screen saver has kicked in over an ill-behaved application which bypasses the
very interrupts the screen saver watches for activity. Your
choices are to try to get from the program's current state
through a successful save-and-exit without being able to see what
you're doing, or to re-boot the machine. This isn't (strictly
speaking) a crash.
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hello sailor! interj.
Occasional West Coast equivalent of hello world; seems to have originated at
SAIL, later associated with the game Zork (which also included "hello, aviator" and
"hello, implementor"). Originally from the traditional hooker's
greeting to a swabbie fresh off the boat, of course. The standard
response is "Nothing happens here."; of all the Zork/Dungeon
games, only in Infocom's Zork 3 is "Hello, Sailor" actually
useful (excluding the unique situation where _knowing_ this fact
is important in Dungeon...).