Check for errors when opening /dev/null as (sort of) requested by Peter Lundblad.
Check for errors when opening /dev/null as (sort of) requested by
Peter Lundblad.

* subversion/libsvn_subr/cmdline.c
  (svn_cmdline_init): Print an error message and return if /dev/null
  cannot be opened.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@850929 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion