Document the fact that if a session is not closed down cleanly then the
session gets removed from the cache and marked as non-resumable.
Fixes #4720
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/6053)
enables applications to obtain information about all sessions sent by the
server.
+A session will be automatically removed from the session cache and marked as
+non-resumable if the connection is not closed down cleanly, e.g. if a fatal
+error occurs on the connection or L<SSL_shutdown(3)> is not called prior to
+L<SSL_free(3)>.
+
In TLSv1.3 it is recommended that each SSL_SESSION object is only used for
resumption once.