2/18    Emacs guru please help.  I am running shell within emacs and have a
        couple hundred lines of text beyond the current prompt, which I use
        one by one as some command argument.  Somehow it just all disappeared
        (from the current prompt to the end).  It is not a c-w because I
        couldn't yank it back.  I didn't save it to another file/buffer.  Is
        there anyway to get it  back?