title: In R, find whether two files differ
body: <p>I would like a pure R way to test whether two arbitrary files are different. So, the equivalent to <code>diff -q</code> in Unix, but should work on Windows and without external dependencies. </p>
  
  <p>I'm aware of <code>tools::Rdiff</code>, but it seems to only want to deal with R output files and complains loudly if I feed it something else.</p>