Source : Free On-Line Dictionary of Computing

RTBM
     
        ({Unix}) Read The Bloody Manual.
     
        {Commonwealth Hackish} variant of {RTFM}.  RTBM is often the
        entire text of the first reply to a question from a {newbie};
        the *second* would escalate to "RTFM".
     
        [{Jargon File}]
     
        (1994-12-08)