/* Async disconnection */
static void
sendCloseSecureChannelAsync(UA_Client *client, void *userdata,
                             UA_UInt32 requestId, void *response) {
    UA_NodeId_deleteMembers (&client->authenticationToken);
    client->requestHandle = 0;

    UA_SecureChannel *channel = &client->channel;
    UA_CloseSecureChannelRequest request;
    UA_CloseSecureChannelRequest_init(&request);
    request.requestHeader.requestHandle = ++client->requestHandle;
    request.requestHeader.timestamp = UA_DateTime_now();
    request.requestHeader.timeoutHint = 10000;
    request.requestHeader.authenticationToken = client->authenticationToken;
    UA_SecureChannel_sendSymmetricMessage(
            channel, ++client->requestId, UA_MESSAGETYPE_CLO, &request,
            &UA_TYPES[UA_TYPES_CLOSESECURECHANNELREQUEST]);
    UA_SecureChannel_close(&client->channel);
    UA_SecureChannel_deleteMembers(&client->channel);
}
void UA_SecureChannel_delete(UA_SecureChannel *channel) {
    UA_SecureChannel_deleteMembers(channel);
    UA_free(channel);
}