Re: inode open

[David Laight <david%l8s.co.uk@localhost>]

On Wed, Jul 16, 2008 at 08:32:24PM -0400, Kurt J. Lidl wrote:
> On Wed, Jul 16, 2008 at 02:46:31PM -0700, Bill Stouder-Studenmund wrote:
> > On Wed, Jul 16, 2008 at 01:15:31AM -0700, Adam Burkepile wrote:
> > > Is there an open function that will open a file based on its inode  
> > > number instead of a path?
> > 
> > Why?
> 
> Well, the traditional answer for this type of interface is "speed".

Especially when releated to the limited number of files that a process
can have open at once.

In certain OS (eg RSX/11M) the lookup and open were different system
calls.  File open was always done by inode number and sequence.
(Modulo rusty brain cells!)

The permissions checks (in the walk to root sequence) don't need to
find any names, just the enclosing directory indoes.  The only problem
one is the first!

        David

-- 
David Laight: david%l8s.co.uk@localhost