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From: eeg@frame.UUCP (Eric Griswold)
Newsgroups: comp.unix.wizards
Subject: Re: What SHOULD go in the kernel
Keywords: device drivers
Message-ID: <3596@frame.UUCP>
Date: 17 Oct 89 22:17:33 GMT
References: <2186@ektools.UUCP>
Reply-To: eeg@frame.UUCP (Eric Griswold)
Distribution: na
Organization: Frame Technology Corp. San Jose, Calif.
Lines: 23

In article <2186@ektools.UUCP> jwr@ektools.UUCP (Jim Reid) writes:
]Unix wizards,
]
]I have some general questions concerning writing Unix device drivers:
]
]Is there a rule of thumb of what should and should not be put in the
]kernel?  

Rule of thumb that I heard from years back:

  If you have determined that there is ABSOLUTELY no way that something 
can be implemented as a user process (as opposed to part of the kernel),
then you need a second opinion.
  If the second opinion agrees with you, then you need to think about it
some more.
  If, after this much thought, there still is no way to implement it as 
a user process, consider putting it in the kernel.

------
  +---   Eric Griswold	| "Eat right. Sleep tight. Get goodly exercise, and
 .+--    eeg@frame.com	| life's full spendor will poke you in the eyes."
( +---)	 sun!frame!eeg	|----------------------------------------------------
 `---'	 ames!frame!eeg	| I just want to disclaim that last disclaimer...