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octal forty /ok'tl for'tee/ n.

Hackish way of saying "I'm drawing a blank." Octal 40 is the

ASCII space character, 0100000; by an

odd coincidence, hex 40 (01000000) is

the EBCDIC space character. See

wall.

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off the trolley adj.

Describes the behavior of a program that malfunctions and goes

catatonic, but doesn't actually crash

or abort. See glitch, bug, deep

space, wedged.

This term is much older than computing, and is (uncommon)

slang elsewhere. A trolley is the small wheel that trolls, or

runs against, the heavy wire that carries the current to run a

streetcar. It's at the end of the long pole (the trolley pole)

that reaches from the roof of the streetcar to the overhead line.

When the trolley stops making contact with the wire (from passing

through a switch, going over bumpy track, or whatever), the

streetcar comes to a halt, (usually) without crashing. The

streetcar is then said to be off the trolley, or off the wire.

Later on, trolley came to mean the streetcar itself. Since

streetcars became common in the 1890s, the term is more than 100

years old. Nowadays, trolleys are only seen on historic

streetcars, since modern streetcars use pantographs to contact

the wire.

The Jargon File, Version 4.2.2, 20 Aug 2000 · 第 1186 / 1941 题