From: Bill Kelly <billk@...>
Date: 2006-03-29T06:26:56+09:00
Subject: Re: timeout when listening with TCPServer

From: "Eric Hodel" <drbrain@segment7.net>
>
>> Oh, hey, cool.  Using the thread there looks like it
>> ought to avoid the issue with Timeout firing in the
>> middle of ensure blocks and circumventing them?
>>
>> I've been avoiding Timeout like "the plague" since
>> running into that behavior.
> 
> You've timed out, so that's what's supposed to happen :)

Haha, yes...  But it can be tricky...

Timeout.timeout 2 do
  sleep 1.9
  mutex.synchronize { @shared << "foo" }
end

...the timeout can fire in such a way that the 
Thread#unlock in the ensure block of Thread#synchronize
is skipped - leaving the mutex locked.

I've been bitten by this... and it was pretty tough to
track down.  (Of course, I was calling some harmless
looking method in the timeout block that just happened
to be using a mutex as part of its implementation...)


Regards,

Bill