>From [EMAIL PROTECTED] Wed Feb 10 01:19:34 1999
>>I hope, that in about 2 years, the sg driver will be replaced by my
>>scg driver which I initially wrote in 1986 for SunOS/Solaris.
>I would welcome even this overall, but I disagree with the device
>addressing scheme of SCG and CAM. It introduces an artificial
>dichotomy between the specialized and generic interfaces, resulting in
>more complex application code (or more likely, lazy application code
>that dumps the responsibility for matching up devices onto the user).
>/dev/sg devices should exist only as placeholders, not a primary
>access mechanism.
I disagree with anything else. Your suggestion introduces this artifical
difference between the SCSI devices and the UNIX device I would have to open.
Are you really suggesting to change the TCP/IP address interface because
it does not conform to the UNIX way of life?
SCSI is protocol with it's own paradigmas and with it's own addressing methods.
If you want to write a generic SCSI access driver you should conform to
the addressing methods of SCSI.
>What are your objections to the BSD style ioctl() interface where
>every specialized device has a generic interaction ioctl? I'm not
This may be present in addition but it does not help for
reasonable SCSI addressing as it makes everything more complex then it
should be.
>referring to specific implementation problems, but rather the idea of
>presenting a generic interface via the specialized scsi device file
>entry. I'm not denying one needs access to the BUS/TARGET/LUN
>numbers, just that these details should not be the responsibility of
>an unsuspecting user. It would be like naming a serial port
Therefore cdrecord supports a scanbus command...
>'0x3f8,irq4' and attaching it to /dev/iogeneric1 (UNIX used to do
>things sorta this way before the idea of specialized interfaces caught
>on. All device drivers were in userspace and applications had to
>include device drivers for all the specific hardware they wanted to
>use. I'd like to think that BSD4.2 was an overall advance in moving
>away from this) instead of just opening /dev/cua0 (and having links to
>/dev/modem and /dev/serial0).
This has nothing to do with the problem discussed above.
>All this hunting and error prone device mapping isn't necessary if one
>lets go of elevating SCSI over the design idiom of the native OS.
This error prone device mapping is only needed on Linux because the
kernel SCSI modules are using the wrong addressing methods.
Hey, I also could name my computer /dev/sol/terra/deutschland/berlin/fokus/...
But it is called *.fkus.gmd.de because the internet community decided to
use this addressing method. To address my computer I need to know the IPaddress
and I know it because I did set it up.
To address a SCSI device, I need to know the bus/target/lun numbers and
I know them because I did set them up when I connected the device
to my machine.
J�rg
EMail:[EMAIL PROTECTED] (home) J�rg Schilling D-13353 Berlin
[EMAIL PROTECTED] (uni) If you don't have iso-8859-1
[EMAIL PROTECTED] (work) chars I am J"org Schilling
URL: http://www.fokus.gmd.de/usr/schilling ftp://ftp.fokus.gmd.de/pub/unix
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