With <filename> a name for the output file to be generated is given. If the element is not given, the software has to choose the name automatically.
A file extension need not to/must not be given, because it is determined by the output file format (see also <fileformat>):
      Format   file extension
    -------------------------
      ASCII         .txt
     (La)TeX        .tex
       PDF          .pdf
    Postscript      .ps
      HTML          .html
     DocBook        .xml
                <filename> must be given only once.
<output>
<fileformat>, <headline>, <lingo>, <remark>
(see also <output>)
<!-- a very imaginative name... :-) -->
<!-- the file extension MUST NOT be given -->
<!-- because it is determined by the file format -->
<filename>table-1</filename>