Subject: Re: detect linkage against openssl or gcrypt

Re: detect linkage against openssl or gcrypt

From: Daniel Stenberg <>
Date: Wed, 31 Jul 2013 13:51:21 +0200 (CEST)

On Tue, 30 Jul 2013, Peter Stuge wrote:

>> I can think of cases where detecting the underlying crypto lib at run-time
>> can be useful or at least helpful.
> Please mention some?

Functionality wise: an libssh2-using application could act differently since
libssh2 is not 100% feature-complete with both backends nor is it entirely
API-agnostic (like one backend supports a NULL argument while the other
doesn't). This might become even more so once we get a third backend

Helpful wise: an application can use the feature to provide information about
libssh2 build version details for debug/report purposes. It is sometimes
easier to ask users to run "myapp --version" to figure out if the libssh2
version it uses has libz built-in, if it is linked to a buggy version of
OpenSSL or if might be that known bug with myapp and gcrypt version Z that's
playing tricks on you.

Received on 2013-07-31