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Re: crash using libcurl 7.19 multi interface

From: Daniel Stenberg <>
Date: Sun, 5 Apr 2009 23:51:24 +0200 (CEST)

On Thu, 2 Apr 2009, Sergii Volchkov wrote:

> So, in my opinion, using curl share can be used as a workaround for the
> described issue, without a need to use synchronous DNS lookup or a-res.
> However, this approach cannot be considered a permanent solution for
> libcurl, since CURLSHOPT_SHARE/CURL_LOCK_DATA_DNS states: "Note that when
> you use the multi interface, all easy handles added to the same multi handle
> will share DNS cache by default without this having to be used!"

Thanks for your research on this topic.

I would say that it indicates a race condition in the multi-threaded resolver
that makes it do bad things unless there's a mutex added and used to prevent
the double access to the same structs.

This fix won't be done by me, I'm not a windows guy.

Received on 2009-04-05