title: How to get the parent dir name for a given dir in erlang?
body: <p>In erlang, i have a dir <code>/proj/htdocs/root/jpT/elqstux/16-04-12/ct_run.ct_sim@esekilvxen263.2016-04-12_09.27.06/auto.suite.sbg_ft_esrvcc_midcall_SUITE.groups.esrvcc_midcall_media_stop_002.logs/run.2016-04-12_09.27.12/log_private/</code>,</p>
  
  <p>I want get the parent dir name of this dir.
  in this case, the expect result is <code>/proj/htdocs/root/jpT/elqstux/16-04-12/ct_run.ct_sim@esekilvxen263.2016-04-12_09.27.06/auto.suite.sbg_ft_esrvcc_midcall_SUITE.groups.esrvcc_midcall_media_stop_002.logs/run.2016-04-12_09.27.12/</code>.</p>
  
  <p>But i try <code>dirname(Filename) -&gt; file:filename_all()</code>, but i am not successed.</p>
  
  <p>So, i want to know is there have this method for this purpose?</p>