Subject: Re: Source for SCSI driver
To: Allen Briggs <>
From: Dan Menchaca <>
List: macbsd-development
Date: 05/03/1995 11:11:04
                      Just when you thought it was safe to leave your
                      RE>>Source for SCSI driver

CAM is a specification that allows one to access a SCSI bus through a common
set of APIs.  This means that from UNIX to UNIX, accessing the SCSI bus will
be the same as far as API calls go.

Future Domain has a CAM interface for DOS/Windows.  Macintosh OS's SCSIManager
4.3, has a CAM-like interface.


ps - for the first question, I'm familiar with coding to some API to send bits
to and fro the SCSI bus.  On UNIX, I'm clueless.  Do they have different APIs
from UNIX to UNIX or is there something more like common I/O method, copying
directly to a /dev file, etc.?
Date: 5/3/95 10:48 AM
To: Dan Menchaca
From: Allen Briggs
> How does one access the SCSI bus in UNIX?  How/when does the ANSI CAM come
> into play?

The first question doesn't really make sense.  You access the SCSI bus
via drivers.  Specifically how depends on the hardware and the system.
Usually, there are at least two drivers between user code and the SCSI
device--the SCSI device driver and the SCSI bus device driver.  The
first would be for, say, the disk or tape or scanner or whatever.  The
second is used by the first to actually get to the device across the

I know very little about CAM, but I got the impression that CAM sits
between the user and the low-level driver--perhaps in conjunction with
or in place of the disk-/tape-/cd-specific drivers.


Allen Briggs - end killing - ** MacBSD == NetBSD/mac68k

------------------ RFC822 Header Follows ------------------ (5.0/1-Nov-1994-eef)
	id AA08360; Wed, 3 May 1995 10:45:05 +0800
	id AA19964; Wed, 3 May 95 13:45:49 -0400 (EDT)
From: (Allen Briggs)
Message-Id: <>
Subject: Re: Source for SCSI driver
To: (Dan Menchaca)
Date: Wed, 3 May 1995 13:45:47 -0400 (EDT)
In-Reply-To: <> from "Dan Menchaca" at May
3, 95 10:36:30 am
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