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Re: Curl, threading and gethostbyname

From: Daniel Stenberg <>
Date: Thu, 26 Aug 2010 23:41:18 +0200 (CEST)

On Thu, 26 Aug 2010, Christian Mauduit wrote:

> I have a mutex for my own calls gethostbyname (so that my program
> serializes its calls to it, for various reasons I prefer this than using
> gethostbyname_r which, among other things, isn't portable)

Just a note that when libcurl is built with the native resolver and ipv4 only,
it will use gethostbyname_r but its "unportability" is not a problem for
libcurl since we support all existing different flavours of it...

> "curl_easy_setopt (curl_handle, CURLOPT_NOSIGNAL, 1);"
> since I read it could help multithreaded UNIX applications (my case).
> So far I didn't reproduce the problem with CURLOPT_NOSIGNAL set

If you use a timeout in your application that could very well explain the
crash and the subsequent fix with CURLOPT_NOSIGNAL, as libcurl uses signals to
timeout name synch resolves by default.

Oh, and you didn't mention which libcurl version you use or what OS you run

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Received on 2010-08-26