[racket-dev] Bug in Racket's I/O?

Thanks --- I've pushed a repair.

At Wed, 20 Jun 2012 20:25:35 -0400, Tony Garnock-Jones wrote:
> Sorry, I should have filed a bug report instead of mailing the list. I'm
> filing the report now.
> 
> On 2012-06-20 8:22 PM, Tony Garnock-Jones wrote:
> > Hi all,
> > 
> > I think I've found a bug in Racket's I/O. Please interpret the following
> > text as relating to the attached tarball with a small example of the
> > problem. The problem manifests for me on both platforms I've tried, OS X
> > and Linux.
> > 
> > When `sync`ing on `read-bytes-evt` at the same time as on `alarm-evt`,
> > it seems that if the `read-bytes-evt` would have come ready but the
> > `alarm-evt` is the one actually chosen, the input from
> > `read-bytes-evt` gets corrupted. This only seems to happen if a single
> > `read-bytes-evt` instance is reused! If a fresh `read-bytes-evt` is
> > constructed every time, the input stream remains uncorrupted.
> > 
> > To see this, run `racket buggy-server.rkt 0`, which uses a single
> > `read-bytes-evt` instance but does not use any `alarm-evt`
> > instances. In another terminal, run `./run-test-osx.sh` (or
> > `./run-test-linux.sh`, as appropriate). The program
> > `./run-test-osx.sh` should terminate without producing any output.
> > 
> > Now, kill off the instance of `buggy-server.rkt`, and start another,
> > this time by running `racket buggy-server.rkt 1`. This instance uses
> > both a single `read-bytes-evt` instance and an `alarm-evt`
> > instance. Now, running `./run-test-osx.sh` should still produce no
> > output, but in fact on most runs, some output (from diffing the input
> > against the output of the socket) is produced, meaning that the echoed
> > output differed from the input.
> > 
> > Regards,
> >   Tony
> > 
> > 
> > 
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> >   http://lists.racket-lang.org/dev
> > 
> 
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