int libssh2_session_disconnect_ex(LIBSSH2_SESSION *session, int reason, const char *description, const char *lang);
int libssh2_session_disconnect(LIBSSH2_SESSION *session, const char *description);
reason - One of the Disconnect Reason constants.
description - Human readable reason for disconnection.
lang - Localization string describing the langauge/encoding of the description provided.
Send a disconnect message to the remote host associated with session, along with a reason symbol and a verbose description.
As a convenience, the macro libssh2_session_disconnect(3) is provided. It calls libssh2_session_disconnect_ex(3) with reason set to SSH_DISCONNECT_BY_APPLICATION and lang set to an empty string.