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Date: Tue, 30 Apr 2002 18:12:37 +0200
From: Peter =?ISO-8859-1?Q?W=E4chtler?= <pwaechtler@loewe-komp.de>
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To: john slee <indigoid@higherplane.net>
CC: Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua>,
        linux-kernel@vger.kernel.org
Subject: Re: [prepatch] address_space-based writeback
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john slee wrote:
> [ cc list trimmed ]
> 
> On Tue, Apr 30, 2002 at 03:19:17PM -0200, Denis Vlasenko wrote:
> 
>>Why do we have to stich to concept of inode *numbers*?
>>Because there are inode numbers in traditional Unix filesystems?
>>
> 
> probably because there is software out there relying on them being
> numbers and being able to do 'if(inum_a == inum_b) { same_file(); }'
> as appropriate.  i can't think of a use for such a construct other than
> preserving hardlinks in archives (does tar do this?) but i'm sure there
> are others
> 
> like much of unix it's been there forever and has become such a natural
> concept in people's heads that to change it now seems unthinkable.
> 
> much like the missing e in creat().
> 

No. Not supplying inode numbers would break unix semantics.
The kernel (and binary loader) depends on a unique key:

major:minor device number + inode


Otherwise: how to decide if a shared object is the same?
checksuming? ;-)

But what would be different with characters? Despite more complexity?


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