Re: /proc/scsi/map

Hi Albert,

On Sun, Jun 16, 2002 at 03:24:33PM -0400, Albert D. Cahalan wrote:

Kurt Garloff writes:

quoted

If we attach a third high-level device driver, two more columns
would show up. (Is this variable column number format a problem?)

The variable column format is of course annoying, but use
it if you must. The also-annoying alternative is to pick
a fill character that would be easy for a beginner to
handle in a script. Maybe one of:  @ - . / ?

Yes, as you correctly mention in your other mail, this would make it easier
to add more columns later.
But the problem then would be that we would need to fix (and limit) the
number of high-level devices that may be reported this way, which is not so
nice either. At this moment it's not a problem, of course, AFAIK.

The header line is far worse. It's too terse to be very helpful.
It gets in the way of every person writing a parser. Even in
your example script, you had to hack your way around it:

I would not call it a hack. Ignoring comment lines is one of the basic
things each parser needs to do. Defining a format that does not allow
for comments actually would not be a very clever move.

But for a file exported from kernel, you may have a valid point.

Actually, the exact format of /proc/scsi/map is certainly something 
that can be discussed separately from the basic idea of adding a file
that does expose the mapping of a SCSI address (CBTU) and the attached
high level drivers. 
The way I designed it just should make it easy for a shell script to use
it. And keeping it simple certainly is a good thing.

Regards,
-- 
Kurt Garloff  [off-list ref]                          Eindhoven, NL
GPG key: See mail header, key servers         Linux kernel development
SuSE Linux AG, Nuernberg, DE                            SCSI, Security