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Re: crash in libeay32.dll if multithreaded.

From: Daniel Stenberg <>
Date: Fri, 14 Feb 2003 10:44:32 +0100 (CET)

On Thu, 13 Feb 2003 wrote:

> I created a multithreaded application on Windows 2000 using libcurl 7.9.6
> with openssl 0.9.6g. It access a non public server using HTTPS.
> When I run multiple instances simultaneously, I occasionally get a crash in
> libeay32.dll of the openssl libraries. It seems to be an access violation
> in the RAND_poll() function related to some heap access. The curl function
> leading to this is Curl_SSLConnect().

Strange. I've not seen this reported before, and I thought it was safe to use
OpenSSL multi-threaded in this way.

> I browsed around the curl and openssl mailing list archives but didn't see
> a solution although at least one other person reported a similar issue with
> open ssl before. The only suggestions in that case was compiling with /MD
> and implementing locking callback functions. The DLLS were compiled with
> /MD, and Curl is supposed to be threadsafe.

I don't know why this happens or even how to proceed. I guess you have some
serious debugging in front of you...

 Daniel Stenberg -- curl, cURL, Curl, CURL. Groks URLs.
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Received on 2003-02-14