title: How to get svn revision previous to specified?
body: <p>I need to automate some task.<br>
  And I need to find svn revision previous to specified revision for specified URL.<br>
  How to do it using <code>svn</code> tool and how to do it in <code>svnkit</code>?</p>
  
  <p>For example I have following history:</p>
  
  <pre><code>D:\wc\trunk&gt;svn log svn://localhost/pg/trunk -q
  ------------------------------------------------------------------------
  r99 | user | 2016-01-27 16:29:11 +0200 (Wed, 27 Jan 2016)
  ------------------------------------------------------------------------
  r98 | user | 2016-01-27 16:28:59 +0200 (Wed, 27 Jan 2016)
  ------------------------------------------------------------------------
  r90 | user | 2016-01-27 16:28:48 +0200 (Wed, 27 Jan 2016)
  ------------------------------------------------------------------------
  r86 | user | 2016-01-27 16:28:35 +0200 (Wed, 27 Jan 2016)
  ------------------------------------------------------------------------
  r85 | user | 2016-01-27 16:28:24 +0200 (Wed, 27 Jan 2016)
  ------------------------------------------------------------------------
  r62 | user | 2016-01-26 18:04:47 +0200 (Tue, 26 Jan 2016)
  </code></pre>
  
  <p>Verbose output:  </p>
  
  <pre><code>D:\wc\trunk&gt;svn log svn://localhost/pg/trunk -v
  ------------------------------------------------------------------------
  r99 | user | 2016-01-27 16:29:11 +0200 (Wed, 27 Jan 2016) | 1 line
  Changed paths:
     M /trunk/f1.txt
  
  Change 4
  ------------------------------------------------------------------------
  r98 | user | 2016-01-27 16:28:59 +0200 (Wed, 27 Jan 2016) | 1 line
  Changed paths:
     M /trunk/f1.txt
  
  Change 3
  ------------------------------------------------------------------------
  r90 | user | 2016-01-27 16:28:48 +0200 (Wed, 27 Jan 2016) | 1 line
  Changed paths:
     M /trunk/f1.txt
  
  Change 2
  ------------------------------------------------------------------------
  r86 | user | 2016-01-27 16:28:35 +0200 (Wed, 27 Jan 2016) | 1 line
  Changed paths:
     M /trunk/f1.txt
  
  Change 1
  ------------------------------------------------------------------------
  r85 | user | 2016-01-27 16:28:24 +0200 (Wed, 27 Jan 2016) | 1 line
  Changed paths:
     A /trunk/f1.txt
  
  Init revision
  ------------------------------------------------------------------------
  r62 | user | 2016-01-26 18:04:47 +0200 (Tue, 26 Jan 2016) | 1 line
  Changed paths:
     A /trunk
  
  1
  ------------------------------------------------------------------------
  </code></pre>
  
  <p>I need to know what revision is before revision 90.<br>
  How to get that previous revision?  </p>