title: tmux pipe-pane not working
body: <p>I have a shortcut defined to start logging a pane to a file, and another to stop logging. The shortcuts are active. These are the commands in my <code>.tmux.conf</code>:</p>
  
  <pre><code>bind-key H pipe-pane "cat &gt;&gt;$HOME/tmux.log"
  bind-key h pipe-pane
  </code></pre>
  
  <p>By pressing <code>C-b ?</code> I am able to see the definition:</p>
  
  <pre><code>   H: pipe-pane "exec cat &gt;&gt;/home/myuser/tmux.log"                                                                                                                                                                                     
     h: pipe-pane                                                                                                                                                                                                                          
  </code></pre>
  
  <p>The idea is that <code>C-b H</code> will start logging and <code>C-b h</code> will stop it, for the current pane. It is clear that different panes will collide, but I am not worried about this now. I just want logging to work, and it does not. The shortcuts seem to work fine, and the file is created alright:</p>
  
  <p>-rw-r--r-- 1 myuser mygroup 0 2012-04-28 11:21 tmux.log</p>
  
  <p>But it <em>always</em> has size 0. Even after closing. Nothing, never ever, gets written to it. Any ideas on how to debug this issue?</p>
  
  <p>This is the only gripe I have with <code>tmux</code> compared to <code>screen</code>, where logging has always been a simple task, working out of the box without any configuration needed.</p>