From: Brian Candler <B.Candler@...>
Date: 2004-09-03T03:48:11+09:00
Subject: Re: Bug? Serial ports and threads don't mix

I've just tried it on a different machine, running FreeBSD-5.2.1, and it all
appears to work correctly (including a more sophisticated program using
timeouts) - so perhaps this is a Linux-ism. I'd still like to know why it
happens though.

The Linux kernel is whatever is the default in a RH9.0 install.

Regards,

Brian.

On Thu, Sep 02, 2004 at 04:41:13PM +0100, Brian Candler wrote:
> Hello,
> 
> I have come across a strange problem with using serial ports under Ruby,
> which comes to light when you try to use a ruby thread (even if this is the
> only thread which is active).
> 
> The attached program demonstrates the problem; it sends three bytes down the
> serial port, then waits for three bytes to be received and displays them. At
> the end, you'll see two very similar ways of starting the object. If you use
> 
>     a = SerialTest.new('/dev/ttyS0')
>     a.test
> 
> then it works; but if you use
> 
>     t = Thread.new do
>       b = SerialTest.new('/dev/ttyS0')
>       b.test
>     end
>     t.join
> 
> then it doesn't, although clearly the two progams should behave identically.
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