On Tue, Dec 26, 2017 at 7:51 PM, Michael Paquier
<michael.paquier@gmail.com> wrote:
>> > Hmm. What about the case where we try to open a plain file that's on
>> > an inaccessible filesystem, e.g. due to a disk failure? Allowing
>> > cancel to work just for FIFOs would be OK, I guess, but allowing it
>> > for other open() calls that hang would be better. I'm not sure if we
>> > can make it work that way, but it would be nice if we could.
>>
>> That is doable, just stat() and check before open().
>
> I think TOCTOU when I read such things.. The data folder is a trusted
> environment but any patches doing things like that ought to be careful.
Yeah. I was more wondering whether an ostensibly non-blocking open()
would nevertheless block on an inaccessible file.
--
Robert Haas
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