[Haskell-cafe] Discussion: The CLOEXEC problem

[Bardur Arantsson]

On 07/24/2015 09:22 PM, Donn Cave wrote:
> Quoth David Turner <dave.c.turner at gmail.com>,
>> Could you be a bit more specific? Which bits of pre-existing software
>> didn't have a FD_CLOEXEC bit and would be broken by this proposal?
> 
> Well, of course to be precise, the bit's always there, it's just
> normally not set - that's the normal environment that anything
> written up to now would expect.  And of course, anything that depends
> on a GHC-opened file to stay open over an exec would be broken.
> I can't enumerate the software that meets that criterion.
> 
>> Since Python recently decided to go through this exact transition, their
>> experience should be instructive. Do you know if there was negative fallout
>> from PEP 0466?
> 
> I gave up on Python a long time ago and don't follow what goes on.
> If recently means less than a decade or so, though, it's not much to
> go on.  If the problem addressed by the O_CLOEXEC proposal is obscure,
> the problems it may create are even more so - I'll certainly concede
> that - and it could take a lot of experience before those problems
> would be well known enough to show up if you went looking for them.
> 

It seems to me that discovering a
"FD-was-unexpectedly-closed-before-it-was-supposed-to" problem is a lot
more likely than discovering FD leaks, no?

(Not that I'm advocating any particular solution to this -- backward
compatibility is a harsh mistress.)

Regards,