documentclass{beamer}
usepackage{tikz}
usepackage{animate}
begin{document}
  begin{frame}
    frametitle{MD5SUM}
     begin{animateinline}[autoplay,loop]{1}
      cat a
      newframe
      cat b
      newframe
      md5sum a
     end{animateinline}
   end{frame}
 end{document}

documentclass{beamer}
  usepackage{beamerthemeWarsaw}
  usepackage{animate}
  usepackage{expl3}
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %command for simulating terminal in/output
  %scroll{<width as TeX dim>}{<number of lines>}{terminal text line}
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  ExplSyntaxOn
  seq_new:Ng_linebuffer_seq
  newcommandscroll[3]{
    ttfamily
    seq_gput_right:Nxg_linebuffer_seq{#3}
    int_compare:nT{seq_length:Ng_linebuffer_seq>#2}{
    seq_gpop_left:NNg_linebuffer_seqdummy
    }
    fbox{begin{minipage}[t][#2baselineskip]{#1}
    seq_map_inline:Nng_linebuffer_seq{mbox{##1}\}
    end{minipage}}
    }
  ExplSyntaxOff

begin{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
begin{frame}[fragile]
  frametitle{Random records}
  How do you randomly select, say 1000 records from a large file?  Use
  the verb|shuf| command
  begin{animateinline}[autoplay,loop]{1}
    scroll{0.8linewidth}{10}{ cat a}%
    newframe
     scroll{0.8linewidth}{10}{clear}
    end{animateinline}
%
end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
begin{frame}[fragile]
  frametitle{Checking for Duplicate Files}
  How do you quickly check whether 2 files are the same? Use the
  verb|md5sum| command.
  begin{animateinline}[autoplay,loop]{1}
    scroll{0.8linewidth}{8}{# echo 1 2 3 > a}
    newframe
    scroll{0.8linewidth}{8}{clear}
  end{animateinline}
end{frame}
end{document}

documentclass{article}

usepackage{courier}
usepackage{animate}
usepackage{expl3}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%commands for simulating terminal in/output
%scroll[<line separator string>]{<width as TeX dim>}
%                             {<number of lines>}{terminal text line}
%clearbuf  %clears line buffer
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
ExplSyntaxOn
seq_new:Ng_linebuffer_seq
seq_new:Ng_inputline_seq
newcommandscroll[4][§§]{
  seq_set_split:Nnng_inputline_seq{#1}{#4}
  seq_map_inline:Nng_inputline_seq{
    seq_gput_right:Nxg_linebuffer_seq{##1}
    int_compare:nT{seq_count:Ng_linebuffer_seq>#3}{
      seq_gpop_left:NNg_linebuffer_seqdummy
    }
  }
  fbox{begin{minipage}[t][#3baselineskip]{#2}
    ttfamily
    seq_map_inline:Nng_linebuffer_seq{mbox{##1}\}
  end{minipage}}
}
newcommandclearbuf{seq_gclear:Ng_linebuffer_seq}
ExplSyntaxOff

begin{document}

  begin{animateinline}[controls,loop]{1}
      scroll{0.9linewidth}{8}{cat a}
    newframe
      scroll{0.9linewidth}{8}{cat b}
    newframe
      scroll{0.9linewidth}{8}{John§§Linda§§Albert§§Francis}
    newframe
      scroll{0.9linewidth}{8}{ln -s a empty.txt}
    newframe
      scroll{0.9linewidth}{8}{md5sum empty.txt}
    newframe
      scroll{0.9linewidth}{8}{d41d8cd98f00b204e9800998ecf8427e  empty.txt}
    newframe
      scroll{0.9linewidth}{8}{md5sum b}
    newframe
      scroll{0.9linewidth}{8}{88a1d2cf7920275378bebdf438bae941  b}
    newframe
      scroll{0.9linewidth}{8}{clear}clearbuf
    newframe
      scroll{0.9linewidth}{8}{}clearbuf
    newframe
    multiframe{10}{i=1+1}{
       scroll{0.9linewidth}{8}{noexpand# Line i}
    }
  end{animateinline}

  begin{animateinline}[controls,loop]{1}
      clearbufscroll{0.9linewidth}{8}{cd /usr/bin}
    newframe
      scroll{0.9linewidth}{8}{echo noexpand$PWD}
    newframe
      scroll{0.9linewidth}{8}{/usr/bin}
    newframe
      scroll{0.9linewidth}{8}{ls -l md5sum}
    newframe
      scroll{0.9linewidth}{8}{%
        -rwxr-xr-x 1 root root 30172 Dec 14 2010
        noexpandbfseriesnoexpandcolor{red}md5sum
      }
    newframe
      scroll{0.9linewidth}{8}{clear}clearbuf
    newframe
      scroll{0.9linewidth}{8}{}clearbuf
  end{animateinline}

end{document}