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From: levy@ttrdc.UUCP (Daniel R. Levy)
Newsgroups: comp.unix.questions
Subject: Re: /dev/null: The final frontier
Message-ID: <1701@ttrdc.UUCP>
Date: Sun, 17-May-87 04:46:18 EDT
Article-I.D.: ttrdc.1701
Posted: Sun May 17 04:46:18 1987
Date-Received: Sun, 17-May-87 19:43:40 EDT
References: <100@upas.UUCP>
Organization: AT&T, Skokie, IL
Lines: 25
Summary: crosspost to net.jokes

In article <100@upas.UUCP>, rcw@upas.UUCP (Robert White) writes:
< Some of these questions may be trivial. I've lost sleep over them:
< 
< Where do the bytes go when moved or copied to /dev/null?
< Does the machine dissipate the data as heat?
< How does a null device driver work?

The UNIX system implementation of /dev/null is such that

write(fd_connected_to_/dev/null,bufferpointer,length)
	/* unsigned length, by definition >= 0 */

will return length without bothering to access the data at bufferpointer,
or (sometimes? always?) even bothering to check if the array of length length
starting at bufferpointer is within a readable part of the process' address
space.

< Robert White
< Graphics Information, Inc.
< UUCP: seismo!hao!scicom!qetzal!rcw
-- 
|------------dan levy------------|  Path: ..!{akgua,homxb,ihnp4,ltuxa,mvuxa,
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