From: ara.t.howard@...
Date: 2006-12-16T05:58:19+09:00
Subject: Re: Thread and sleep

On Sat, 16 Dec 2006, Tim Pease wrote:

>> I had this problem on a project a couple of years back and the
>> conclusion of those who helped me from this group was that the io on
>> stdin was blocking all threads other threads while the thread with the
>> stdin io (gets) waited for input. I seem to recall someone saying that
>> this prevented two or more threads from trying to read from stdio at
>> the same time.  Does this still ring true/correct?  And the work around
>> as I recall was to use a windows system call to check for input being
>> ready before the thread tried to read from stdin so the others were
>> blocked as little as possible.
>> 
>
> Yeah, it does look like the "gets" is causing the other thread to not
> wake up from sleep. This is really odd, though, since the other thread
> is just sleeping and not trying to do any IO whatsoever.  Hmmm ...
> maybe the puts and the gets are not playing well together?
>
> I use the gets line in little test applications to keep the thing
> running until I hit enter. Then I do cleanup, etc.  So it's nothing
> mission critical, but it is very unexpected behavior.  Possible bug?

i bet it involves ruby's internal use of select for thread scheduling and
diffent input methods generated by mvc++ vs. msys being responsible for
dictating whether this blocks ruby or not.

-a
-- 
if you find yourself slandering anybody, first imagine that your mouth is
filled with excrement.  it will break you of the habit quickly enough. - the
dalai lama