Source : Free On-Line Dictionary of Computing

RTFB
     
         (By analogy with {RTFM}) Read The Fucking
        Binary.
     
        Used when neither {documentation} nor {source} for the problem
        at hand exists, and the only thing to do is use some
        {debugger} or {monitor} and directly analyse the {assembler}
        or even the {machine code}.
     
        "RTFB" is the least pejorative of the RTF? forms, the anger is
        directed at the absence of both source *and* adequate
        documentation rather than at the person asking a question.
     
        [{Jargon File}]
     
        (1995-08-20)