bug#28596: 26.0.60; [Gnus] Checking mail is no longer reliable and C-g no longer quits

[N. Jackson]

Hello Eli,

At 19:40 +0200 on Saturday 2017-12-02, Eli Zaretskii wrote:
>
> Any news on this? Is this problem still present in the Emacs
> 26.0.90 pretest?

Yes, the problem is still present with the 26.0.90 pretest. I ran
that for three weeks and the problem happened almost every day.

Then I went back to using Emacs 25 out of frustration.

No, sorry, no news. I wasn't able to get any traction on debugging
it; that would be so much easier if the code were in C! (I am
perennially unsuccessful when I try to get the Elisp debugger to
function the way I think it ought to, probably because I don't
understand the way it is supposed to work.)

However, I had forgotten (or never saw) your suggestions to

  "try setting url-asynchronous to nil when fetching news... [o]r
  maybe even build Emacs with HAVE_GETADDRINFO_A undefined"

and I will try that with 26.0.90 these next days.

Additionally, I am almost convinced that the problem is that Gnus
gets into an ambiguous state where part of it thinks it is
"unplugged" and part of it thinks it's "plugged", and that it
never even tries to retrieve the news in the cases where it seems
to be "broken".

Furthermore, I now believe that the hang that I had been observing
was just Bug 16026 / Bug 16906 and that I failed to recognise it
because I was too confused by the strange behaviour resulting from
this current bug.

N.