title: How to fetch a Subversion external without fetching all other directories and subdirectories
body: <p>I have a Subversion repository called 'repo'. Inside of repo are trunk/ and branches/ directories. Within branches/ there are several dozen release branches, e.g. 1.0/, 1.1/. These branches/ directories contain a relatively large application.</p>
  
  <p>I want to add an external at the root of repo, called 'myExternal'. When I define the external, the only way to get SVN to create the myExternal/ directory is to run 'svn up' from the root of repo. However, this will also cause the entire contents of branches/ to be checked out, which is unacceptable (we have many developers that need to get myExternal/ added to their copy of repo, and can't have all of them checking out gigabytes of unneeded branches).</p>
  
  <p>I've tried 'svn up --set-depth immediates', but that doesn't seem to get the externals. Is there any way to tell svn to fetch myExternal/ without fetching all of branches/ ?</p>
  
  <p>Using SVN 1.7.</p>