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Re: Regarding Error - OpenSSL SSL_connect: SSL_ERROR_SYSCALL

From: Daniel Stenberg <>
Date: Thu, 31 Aug 2017 09:29:09 +0200 (CEST)

On Thu, 31 Aug 2017, Rahul Sabnis via curl-library wrote:

> I have built CURL (Version: 7.54.0) with SSL.

On which platform?

> *./configure --prefix=$(INSTALL_DIR) --enable-http --with-ssl=<OpenSSL
> Install Dir> --enable-cookies --enable-shared=yes --enable-static=no
> --without-zlib --disable-gssapi --disable-ldap --disable-ldaps
> --disable-unix-sockets --disable-rtsp*
> The built library does not show any dependency on libssl/libcrypto

At the end of the configure run it displays a lot of info about what it found
and thus what features that will be used/enabled in the build. Does that
summary state that it has SSL support enabled? It should even say "OpenSSL" on
that line.

> When I use this library in my application, I see below error:
> *OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to
> <>*

So you say it still uses OpenSSL without "depending" on it ? Wouldn't that
imply that you're actually using another build/library than the one you

> ** OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to

That's an error code returned from OpenSSL's SSL_connect() function. I presume
that happens because something bad happens.

> Same works fine on Linux & Solaris, for both HTTP as well as HTTPS.

I trust "same" means SSL connections to the same server. I think that would
hint on a problem in the OpenSSL version you run here. Either a version
dependent problem or an architecture dependent problem as by your wording I
assume the problem isn't on Linux or Solaris but on something else.

> Looking at the above error I am assuming right now that libcurl is linked to
> OpenSSL. Is that correct ?

Yes, and that is shown both in the configure summary and in `curl -V` output.

> 3. Is any system configuration causing this problem ?

I don't know. OpenSSL seems to detect a problem and return that error. I don't
know why...

Received on 2017-08-31