has anyone installed 5.1 from a SCSI CD?

Sergey Babkin babkin at bellatlantic.net
Mon Sep 29 17:29:51 PDT 2003


Peter Jeremy wrote:
> 
> On Sun, Sep 28, 2003 at 06:14:25PM -0400, Sergey Babkin wrote:
> >BTW, I have another related issue too: since at least 4.7
> >all the disk device nodes have charcater device entries in /dev.
> 
> As of December 1999 - which is before 4.0-RELEASE.  This was well
> advertised and discussed at the time.  Your objections are about
> 4 years too late.

Well, the previous version I installed was 4.0-snapshot
that did not have this change yet. Also it's never too late
to fix the broken things.

> >That's very, very wrong. Even though there may be no difference
> >any more between the charcater and block drivers, the type of
> >device node still conveys the information about device types
> >to the applications. One case in point being a viewer application
> >(if anyone is interested, http://nac.sf.net ) which must handle
> >the sequential and random-access devices differently:
> 
> 'block' vs 'character' has nothing to do with random or sequential
> access and any application that thinks it does is broken.  Any
> application that directly accesses devices must understand all the
> various quirks - ability to seek, block size(s) supported, side-

The random-access devices are seekable by definition. And the
OS interface is there to hide the block size issues.

> The only purpose for block devices was to provide a cache for disk
> devices.  It makes far more sense for this caching to be tightly
> coupled into the filesystem code where the cache characteristics
> can be better controlled.

What I'm saying is that it's good to have an easy way for
applications to distinguish the random-access devices from the
sequential-only-acces devices. Are they cacned internally or
not is not that much of an application's concern.

-SB


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