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Re: transactions stall after March 6 commit to improve wakeup and wait code in multi

From: Bryan Henderson via curl-library <curl-library_at_lists.haxx.se>
Date: 15 Jun 2026 18:55:27 +0000

> >> But after the subject commit, the file descriptor never becomes ready to
> >> read. My code eventually times out as a failsafe and calls
> >> curl_multi_perform anyway, and the transaction does in fact advance.
> >> After that, the pselect/curl_multi_perform loop properly completes the
> >> transaction.
> >>
> >> Is this a bug, or is the algorithm above not supposed to work?
>
> This sounds like it could be a possible bug.
>
> Any chance you can for example modify an existing example source code to
> reproduce this behavior? Then we would have a good reproducer to work with!

I'll see what I can do. I've already done the hardest part -- built libcurl
8.20 and reproduced the problem myself using my simplest Xmlrpc-c example
program (all reproductions before were done by an Xmlrpc-c user using his own
Xmlrpc-c application).

I also confirmed that the stall happens before any contact is attempted with
the server, so we don't need a server running to reproduce it.

Now all I have to do is distill the libcurl interactions into a simple
reproducer program.

-- 
Bryan Henderson                                   Omak, Washington
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Received on 2026-06-15