title: how to commit modified file into repository
body: <p>I have a file in my repository that has been modified. i.e it shows 'M' next to the file when I hit 'svn st'. How do I get it to show an 'A' so I can svn commit it? </p>
  
  <p>I've tried <code>svn update "filename.c"</code> and it doesn't do the trick.</p>
  
  <p>thanks</p>