cmp or strcasecmp or perhaps strcoll, if null then strcmp is used.
  - use null as argument for "after"-entry when searching the first
  matching entry, otherwise the last returned value if you look for other
  entries with a special "compare" function (if null then a doubled search
  is rather useless with this variant of _findfile).
</p>
</td></tr><tr><td valign="top"><p>
  The <code>zzip_disk_findfirst</code> function is the first call of all the zip access functions here.
  It contains the code to find 