Re: read_proc issue

[Erik Mouw]

On Wed, Feb 27, 2002 at 09:42:04PM +0000, Alan Cox wrote:
> > I've encountered this problem before, too.  What is the "One True Way"
> > to do this cleanly?  In other words, if you want to do a calculation
> > once every time someone runs "cat /proc/foo", what is the cleanest way
> > to do that?  The solution we came up with was to check the file offset
> > and only do the calculation if offset == 0, which seems pretty
> > hackish.
> 
> Another approach is to do the calculation open and remember it in per
> fd private data. You can recover that and free it on release. It could
> even be a buffer holding the actual "content"

It might also be an idea to export proc_calc_metrics() from
fs/proc/proc_misc.c because quite a lot of code actually tries to do
exactly the same.

Erik

-- 
J.A.K. (Erik) Mouw, Information and Communication Theory Group, Faculty
of Information Technology and Systems, Delft University of Technology,
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