libssh2_userauth_list - list supported authentication methods

session - Session instance as returned by libssh2_session_init_ex(3)username - Username which will be used while authenticating. Note that most server implementations do not
       permit  attempting  authentication  with different usernames between requests. Therefore this must be the
       same username you will use on later userauth calls.

       username_len - Length of username parameter.

       Send a SSH_USERAUTH_NONE request to the remote host. Unless the remote host is configured to accept  none
       as a viable authentication scheme (unlikely), it will return SSH_USERAUTH_FAILURE along with a listing of
       what  authentication  schemes  it  does support. In the unlikely event that none authentication succeeds,
       this method with return  NULL.  This  case  may  be  distinguished  from  a  failing  case  by  examining
       libssh2_userauth_authenticated(3).

LIBSSH2_ERROR_ALLOC - An internal memory allocation call failed.

       LIBSSH2_ERROR_SOCKET_SEND - Unable to send data on socket.

       LIBSSH2_ERROR_EAGAIN - Marked for non-blocking I/O but the call

       libssh2_userauth_list - list supported authentication methods

       On success a comma delimited list of supported authentication schemes. This list is internally managed by
       libssh2. On failure returns NULL.

libssh2_session_init_ex(3)

libssh2 0.15                                       1 Jun 2007                           libssh2_userauth_list(3)

       #include <libssh2.h>

       char *
       libssh2_userauth_list(LIBSSH2_SESSION *session,
                             const char *username,
                             unsigned int username_len);