From: zlsiial@uts.mcc.ac.uk (A. V. Le Blanc) Subject: Device names (was Re: ttys2 not responding) Date: 7 Jul 1992 07:15:04 GMT
In article <1992Jul3.053109.22436@muddcs.claremont.edu> jwinstea@jarthur.claremont.edu (Jim Winstead Jr.) writes:
>Unless you have a non-standard setup, there is no such thing as
>/dev/ttys0. /dev/ttys1 *does* correspond to COM1 under DOS, and so
>forth.
>
>/dev/ttys1 has major 4, minor 64 (ie. mknod /dev/ttys1 c 4 64), and
>the others increment the minor number from there.
And almesber@nessie.cs.id.ethz.ch (Werner Almesberger) writes:
>In article <Bqtqrs.C7x@news.cso.uiuc.edu> thoth@uiuc.edu (Ben Cox) writes:
>> "Non-standard" = MCC-interim 0.95c+, which comes with /dev/ttys[0-3].
>
>MCC-interim and the rootdisk (and the ABC-release) really should agree on
>device names. This avoids many problems when communicating about devices
>(documentation, FAQs, bug reports, configuration questions, etc.) and
>reduces the risk that somebody writes configuration scripts that
>accidentially work on the wrong device.
>
>The issue of device names has been discussed long ago on the
>linux-standards mailing list, so we probably don't have to go through
>this again.
As the person who gave you /dev/ttys0 in the first place, I would
like to say that I renamed the ttys? devices according to my
understanding of the discussion in the Linux-standards mailing list,
to which I subscribe. I also renamed the fdxxxxx devices according
to the discussion in the same list. So far as I know, neither
discussion actually came up with an agreed conclusion.
The ttys? discussion was a tug of war between the Unixers (who like
devices with 0 origin) and the DOSsers (who like compatibility with
MS-DOS). On this question it seemed to me that the Unixers had
better arguments.
The fd* discussion had much less unanimity. I was myself fed up
with the Minix device names, which I could never remember, and
decided to adopt the attractive proposal made by Linus himself at
nearly the end of the discussion: /dev/fd0H1440, for example, means
floppy disk drive 0 (opposed to 1), with high density (opposed to
Q or D or S) on a 3 inch drive (H-Q-D-S for 3 inch drives, h-q-d-s
for 5.25 inch drives) and 1440 kilobytes accessible (instead of
1200, 720, 360, etc).
There was also a discussion of the names for SCSI devices. In the
latest MCC version I have used sda, sda1..sda8, sdb, sdb1..sdb8,...,
..sde8; these were one of the suggestions made at the time, and
conform to the hda/hdb pattern. There were also suggestions for
distinguishing between controller cards and other complications.
As far as I know, the scheme I have adopted has only one disadvantage:
many people don't like it. No definitive solution can be found in
the documents in /pub/Linux/standards at banjo.concert.net, but the
other discussions are in mail-archives in the same directory.
-- Owen
LeBlanc@mcc.ac.uk