[libvirt] stat() vs. access()

Daniel P. Berrange berrange at redhat.com
Thu Nov 12 11:23:42 UTC 2009

On Sun, Nov 08, 2009 at 12:52:35AM +0100, Maximilian Wilhelm wrote:
> Hi!
> While discussing some code with Matthias, we stumbled across many occurances
> of stat() calls within the libVirt code (virFileExists() for example) which
> could be implemented in a cheaper way when using access() instead of stat(),
> when the only purpose is to check for the existance of a file.
> The one thing I'm concerned about, is the question if access() does the right
> thing in all situations. As the manpages didn't tell anything about
> directories it might be worth to clarify this in advance.
> A simple practical test showed that
>   access ("/path/to/dir", F_OK)
> seems to work as expected.
> Any comments on these (optimization) thoughs?

I don't see any problems with this idea, so if you want to do the conversion
go for it.

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