RCommandClient is very similar to
org.apache.commons.net.bsd.RExecClient ,
from which it is derived, and implements the rcmd() facility that
first appeared in 4.2BSD Unix.
RLoginClient is very similar to
org.apache.commons.net.bsd.RCommandClient ,
from which it is derived, and uses the rcmd() facility implemented
in RCommandClient to implement the functionality of the rlogin command that
first appeared in 4.2BSD Unix.