@deftypefun {const char *} {gnutls_psk_server_get_username} (gnutls_session_t @var{session})
@var{session}: is a gnutls session

This should only be called in case of PSK authentication and in
case of a server.

The returned pointer should be considered constant (do not free) and valid 
for the lifetime of the session.

This function will return @code{NULL}  if the username has embedded NULL bytes.
In that case, @code{gnutls_psk_server_get_username2()}  should be used to retrieve the username.

@strong{Returns:} the username of the peer, or @code{NULL}  in case of an error,
or if the username has embedded NULLs.
@end deftypefun