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Re: epoll exposure

>>> The problem is third-party software assumes epoll == Linux,

>> Software that makes stupid assumptions will never go away.

>> Is it better to work around it (not ship epoll.h), or to get it
>> fixed (report it upstream as the bug it is)?  I could argue that
>> either way.

> I don't really see it as a bug.  You'd have to have all those
> problems have configure logic that says

>   if we find an epoll implementation, then we have a list of
>   operating systems that have implemented an epoll that has different
>   semantics and we have to reject it

That's not about assuming "epoll == Linux".  That's about assuming
"epoll, if present, has exactly Linux's epoll semantics".  While it's
possible that either would break on the epoll under discussion, they
are not equivalent assumptions in general.

It also is a wrong way to build self-configuration; such a test is
vulnerable to both false positives and false negatives.  It should be
reported upstream as a bug.  Much righter is to test whether epoll, if
present, produces the behaviour the program expects in the uses it
makes of it.  (Also, "Linux" is not a single thing, so "epoll == Linux"
cannot be a correct thing to assume even conceptually.)

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