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Date: Wed, 22 Oct 2003 18:55:14 +0930
From: Greg 'groggy' Lehey <grog@FreeBSD.org>
To: rk47 <rk@nanoteq.co.za>
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Subject: Re: What is a "unit" number of a device
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On Tuesday, 21 October 2003 at 13:25:20 +0200, rk47 wrote:
> What is a "unit" number of a device

That depends a lot on the device.  For SCSI disks, you select the unit
number on the drive itself.

> and how does it relate to the minor number of the device.

Typically the last few bits of the minor number map directly to the
unit number.

> Is there a generic relationship or dowes it differ between devives.

"Yes".

Look at the section man page for the device in question.  It *should*
give that mapping.  If it doesn't, the header files are (maybe) your
friend.

Greg
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