The default lowat level for gnutls-2.12* is set to zero to avoid
unnecessary system calls and the gnutls_transport_set_lowat function has
been totally removed in >=gnutls-3 which causes build failures.
Therefore, the function shouldn't be used except for versions that
require it, <gnutls-2.12.0.
gnutls_transport_set_push_function(session, Curl_gtls_push);
gnutls_transport_set_pull_function(session, Curl_gtls_pull);
+#if GNUTLS_VERSION_NUMBER < 0x020c00
/* lowat must be set to zero when using custom push and pull functions. */
gnutls_transport_set_lowat(session, 0);
+#endif
/* This might be a reconnect, so we check for a session ID in the cache
to speed up things */