RE: EPICS on RTEMS crashing on CA access, due to GNU readline?!?

["Jeff Hill" <johill@lanl.gov>]

Hi Angus,

Maybe this isn't relevant, but I seem to recall that recently the way that the SIGALARM was ignored by the channel access client library was changed. As I recall, an ignore handler that was being installed for certain threads (maybe it wasnt per-thread but per -process on OS that had problems) was removed in favor of adding code restarting the system call, if appropriate, when interrupted.

Jeff
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> -----Original Message-----
> From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov]
> On Behalf Of Angus Gratton
> Sent: Tuesday, May 03, 2011 8:41 PM
> To: tech-talk
> Subject: Re: EPICS on RTEMS crashing on CA access, due to GNU readline?!?
> 
> On Tue, 2011-05-03 at 16:07 +1000, Angus Gratton wrote:
> > I have a _very_ unusual bug that I'm currently working through.
> >
> > *snip*
> 
> Against all intuition, it looks like my bug has something to do with
> POSIX signal handlers for RTEMS.
> 
> Readline wraps several POSIX signals by default while waiting on
> standard input, something in that process trips the bug. Disabling
> HANDLE_SIGNALS in rlconf.h before building readline fixes the problem.
> 
> I've done some more extensive debugging, enabling and disabling the
> different signal handlers, but I can't seem to nail it down to any
> particular signal. It feels to me like an internal RTEMS bug at this
> point, although it's hard to tell.
> 
> I can't afford much more time on it, so I'm just building readline
> without HANDLE_SIGNALS for now.
> 
> - Angus