Clearing O_NONBLOCK from a pipe may lose data

Lasse Collin lasse.collin@tukaani.org
Thu Feb 26 19:44:00 GMT 2015


On 2015-02-24 Corinna Vinschen wrote:
> On Feb 24 16:16, Lasse Collin wrote:
> > I'm going to release xz 5.2.1 in a day or two. Should that release
> > have a workaround for this Cygwin bug? The workaround would avoid
> > using O_NONBLOCK on stdout. It adds a race condition to signal
> > handling in xz but it's usually a very minor issue (xz 5.0.x has
> > the race and no one has complained). On the other hand, the fixes
> > to the threading bugs are somewhat important for xz too, so maybe I
> > should just add a note that xz 5.2.x isn't safe on Cygwin yet but
> > will be in the (somewhat) near future?
> 
> Whatever you prefer.  I think it's fine to point to using at least
> Cygwin 1.7.35, but if you can live with updating to some 5.2.2 after
> 1.7.35 comes out, the workaround in 5.2.1 would be nice.
> 
> I'm still working on performance improvements in the account handling,
> but when that's settled, I'm going for 1.7.35.  Let's say a week or
> two.

OK, thanks. I decided to tell people to use 1.7.35 or later. The
threading issues are one reason. Another reason is that if the
workaround is removed in 5.2.2, 5.2.1 will become a special release
that (mostly) worked on older Cygwin versions. I prefer to tell users
of old Cygwin version to use xz 5.0.x.

-- 
Lasse Collin  |  IRC: Larhzu @ IRCnet & Freenode

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