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Date: Mon, 11 May 2009 09:23:42 -0500
From: Brian Ford <Brian DOT Ford AT FlightSafety DOT com>
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Subject: Re: How to detect a cygwin thread?
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On Mon, 11 May 2009, Piotr Wyderski wrote:

> Christopher Faylor wrote:
>
> > Yes, that's the signal thread but I don't know why stopping it would
> > cause any special problems since, if the entire program is stopped, it
> > isn't going to be processing signals.
>
> I don't know the reason, just report the program's
> behaviour. But to provide you more context: this
> code is a critical error handler. All it has to do is:
>
> 1. immediately stop the world in a nice way,
> as this thread is all about. When "sig" is suspended,
> no more points follow.
>
> 2. dump detailed stack traces + module list +
> the emergency stop reason description to
> the set of log files;

My WAG is:

http://www.cygwin.com/ml/cygwin-developers/2007-10/msg00040.html

A handshake with the signal thread is required for many Cygwin system
calls to proceede.

> The need for parsing DWARF sections by the
> user himself is a difficult and painstaking challenge.

Have you considered libdwarf?  I have a build that works using a custom
minimal libelf stub library.  I don't use if for back traces at the
moment, but it can read symbolic program variable information.

-- 
Brian Ford
Staff Realtime Software Engineer
VITAL - Visual Simulation Systems
FlightSafety International
the best safety device in any aircraft is a well-trained crew...

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