From: Eric Schwartz <eric.schwartz@...>
Date: 2004-09-01T03:17:21+09:00
Subject: Re: Ruby is eating my signals!

I don't mean to be pushy, but this is causing me some fairly sizable
pain at the moment; does anyone have an idea as to how I can fix my
extension (or alternatively, how to force Ruby to deliver a signal it's
currently deferring)?

Thanks,

-=Eric

On Wed, 2004-08-25 at 13:11, Eric Schwartz wrote:
> I posted this to comp.lang.ruby, but got no replies.  Perhaps it's more 
> appropriate here.
> 
> I've built a Ruby extension for STAF (<URL:http://staf.sf.net/>) that is
> mostly working well.  However, sometimes the STAF query goes off into
> the weeds.  I want to set up a timeout that sends a SIGALRM to the main
> process, but that SIGALRM is not getting propogated to my Ruby program. 
> The interpreter is receiving the signal, but isn't passing it along.
> 
> I instrumented signal.c, and what I've found is that sighandler is being
> called for the SIGALRM.  In it, rb_trap_immediate is NOT set, so
> rb_trap_pending is incremented, and the SIGALRM entry in trap_pending
> list is incremented.  So far so good-- it appears this is Ruby's way of
> deferring handling of signals until it's safe to handle them.
> 
> The problem is, this signal is never getting handled.  And, well, kinda
> the point of a SIGALRM is that it gets sent in a reasonably timely
> manner. :)  I've noticed this behaviour seems to exist with every
> signal, though, except SIGSTOP and SIGKILL (for obvious reasons).
> 
> Is there something I'm doing wrong in my STAF extension? (You can get
> source at http://sourceforge.net/tracker/?group_id=33142&atid=407383 if
> you want to double-check me.)  Is there some way to force Ruby to
> deliver this signal?  How can I tell why it's not being delivered?
> 
> Thanks for any help,
> 
> -=Eric
-- 
Eric Schwartz <eric.schwartz@hp.com>
Hewlett-Packard Company Linux/Open Source Labs (LOSL)