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From: chris@umcp-cs.UUCP (Chris Torek)
Newsgroups: net.unix-wizards
Subject: Re: magtape device naming conventions
Message-ID: <3720@umcp-cs.UUCP>
Date: Mon, 6-Oct-86 22:50:13 EDT
Article-I.D.: umcp-cs.3720
Posted: Mon Oct  6 22:50:13 1986
Date-Received: Wed, 8-Oct-86 07:07:15 EDT
References: <3957@brl-smoke.ARPA> <256@decvax.UUCP> <7711@sun.uucp>
Reply-To: chris@umcp-cs.UUCP (Chris Torek)
Organization: University of Maryland, Dept. of Computer Sci.
Lines: 43

>>How about the following? ...while {l,m,h} is "l"ow, "m"edium, or "h"igh
>>density depending on make and model of the drive.

In article <7711@sun.uucp> guy@sun.UUCP writes:
>While the scheme used in S5R2 shares the same unfortunate tendency to use a
>single letter (the same "l", "m", or "h") when a longer description ("800",
>"1600", or "6250") would be clearer, at least it provides a standard way of
>getting at a given drive at a specified density; "l" is always 800, "m", is
>always 1600, and "h" is always 6250.

Shades of EXEC-8!

But no: there `l', `m', and `h' stand for `low', `medium', and
`high' density, but these are 556, 800, and 1600 bpi respectively.
What did they use for 6250 bpi?  `s': `super-high density'.

>There should be a standard way of requesting a particular density
>that will work on all drives that support that density; the numerical
>value of the density should appear in the name used to select that
>density.

I agree.

Hey, this is Unix:

	mkdir /dev/tape
		# SysVish names (make corrections if required)
	ln /dev/rmt0 /dev/tape/rl0	#    rewind, raw, l=800,  drive 0
	ln /dev/rmt4 /dev/tape/nrl0	# no rewind, raw, l,      drive 0
	ln /dev/rmt8 /dev/tape/rm0	#    rewind, raw, m=1600, drive 0
	ln /dev/rmt12 /dev/trape/nrm0	# no rewind, raw, m,	  drive 0

		# more reasonable? names
	ln /dev/rmt0 /dev/tape/r9t800r0	  # raw, 9trk,  800, rewind, drive 0
	ln /dev/rmt4 /dev/tape/r9t800n0	  # raw, 9trk,  800, no rew, drive 0
	ln /dev/rmt8 /dev/tape/r9t1600r0  # raw, 9trk, 1600, rewind, drive 0
	ln /dev/rmt12 /dev/tape/r9t1600n0 # raw, 9trk, 1600, no rew, drive 0

No one says we have to use only one convention.  What are links for?
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 1516)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris@umcp-cs		ARPA:	chris@mimsy.umd.edu