open(redirected from open on)
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1. Nautical free from navigational hazards, such as ice, sunken ships, etc.
a. (of a violin or guitar string) not stopped with the finger
b. (of a pipe, such as an organ pipe) not closed at either end
c. (of a note) played on such a string or pipe
a. in operation; active
b. unrestricted; unlimited
4. (of a wound) exposed to the air
5. (esp of the large intestine) free from obstruction
6. Chess (of a file) having no pawns on it
7. Maths (of a set) containing points whose neighbourhood consists of other points of the same set
8. Computing (of software or a computer system) designed to an internationally agreed standard in order to allow communication between computers, irrespective of size, maufacturer, etc.
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
Condition in which conductors are separated so that current cannot pass.
Break or discontinuity in a circuit which can normally pass a current.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
To prepare to read or write a file. This usually involves checking whether the file already exists and that the user has the necessary authorisation to read or write it. The result of a successful open is usually some kind of capability (e.g. a Unix file descriptor) - a token that the user passes back to the system in order to access the file without further checks and finally to close the file.
Abbreviation for "open (or left) parenthesis" - used when necessary to eliminate oral ambiguity. To read aloud the LISP form (DEFUN FOO (X) (PLUS X 1)) one might say: "Open defun foo, open eks close, open, plus eks one, close close."
Non-proprietary. An open standard is one which can be used without payment.
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)
open(1) Not proprietary. See open architecture, open system and open source. Contrast with closed architecture and closed system.
(2) To "run" a program (application). Open means "load the program and run it" or "launch the program and run it."
(3) To engage a digital file. From the user's point of view, open also means to read the first block of data. From the programmer's standpoint, open is the first step, and "read the first block of data" is the next. Contrast with close.
(4) To open a switch means to stop current from passing through. The switch is "off." See switch.
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