open

1. 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.

2. 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."

3. Non-proprietary. An open standard is one which can be

used without payment.

[Jargon File]

(1995-01-31)