OpenSSL version number when compiling

[Viktor Dukhovni]

On Wed, Aug 02, 2023 at 06:32:22AM +0000, Dr. Matthias St. Pierre via openssl-users wrote:

> > #if OPENSSL_VERSION_NUMBER > 0x30100ff0L
> 
> Kenneth, is it possible that you didn't include opensslv.h?  IIRC, the
> expression evaluates to #if 0 > 0x30100ff0L if OPENSSL_VERSION_NUMBER
> is not defined.
> 

Perhaps see also:

    https://github.com/vdukhovni/postfix/blob/master/postfix/src/tls/tls_misc.c#L1358-L1409

Some older 0.x OpenSSL releases used a different encoding, but they're
long obsolete:

    https://github.com/vdukhovni/postfix/blob/postfix-2.3/postfix/src/tls/tls_misc.c#L437-L521

--
    Viktor.