Allow SSL_write(..., n) to return r with 0 < r < n (i.e. report success
when just a single record has been written). When not set (the default),
SSL_write() will only report success once the complete chunk was written.
+Once SSL_write() returns with r, r bytes have been successfully written
+and the next call to SSL_write() must only send the n-r bytes left,
+imitating the behaviour of write().
=item SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER
flag SSL_MODE_AUTO_RETRY will cause read/write operations to only
return after the handshake and successful completion.
+=item SSL_MODE_RELEASE_BUFFERS
+
+When we no longer need a read buffer or a write buffer for a given SSL,
+then release the memory we were using to hold it. Released memory is
+either appended to a list of unused RAM chunks on the SSL_CTX, or simply
+freed if the list of unused chunks would become longer than
+SSL_CTX->freelist_max_len, which defaults to 32. Using this flag can
+save around 34k per idle SSL connection.
+This flag has no effect on SSL v2 connections, or on DTLS connections.
+
=back
=head1 RETURN VALUES