Re: signal handling different in 1.8.3 than 1.8.1?

[Gregory Marton]

Hi Ludovic,

> The following message is a courtesy copy of an article
> that has been posted to gmane.lisp.guile.bugs as well.

Is address@hidden now out of date?   I may have to get a newsreader. 
Are they mirrored?


> > Now that I've upgraded to 1.8.3 from 1.8.1, some old test cases are
> > failing.  In particular:
>
> According to `NEWS', there were no signal-related changes.

Nevertheless, it has consistently passed in 1.8.1 and consistently fails in 
1.8.3 with no other changes.


> > (define (ensure body-lambda ensuring-lambda)
> >    (dynamic-wind
> >        (lambda () #t)
> >        body-lambda
> >        ensuring-lambda))
> >
> > (define (with-sigaction signum handler flags lamb)
> >      (let ((old-sigaction (sigaction signum)))
> >        (if flags (sigaction signum handler flags) (sigaction signum handler))
> >        (ensure
> >         lamb
> >         (lambda ()
> >           (sigaction signum (car old-sigaction) (cdr old-sigaction))))))
>
> Signal handlers are invoked asynchronously as system asyncs, and system
> asyncs are run whenever `SCM_TICK' is encountered in the C code.
>
> There doesn't seem to be any Scheme procedure to force the execution of 
> system asyncs, but maybe you can try invoking LAMB above in 
> `call-with-unblocked-asyncs' and/or adding a `(sleep 0)' right before it 
> to force the execution of pending system asyncs.
>
> Let us know if it helps.

call-with-unblocked-asyncs complains:
    misc-error: asyncs already unblocked

With (sleep 0) is no different than without.

Thank you,
Grem

--
------ __@   Gregory A. Marton                http://csail.mit.edu/~gremio/
--- _`\<,_                                                                .
-- (*)/ (*)               I came, I saw, I thunked, I flunked.
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