<para>
  When this option is enabled, we write an additional column called 'Filename'.
  The values of this column are filled with filenames of previous input formats.
</para>
<para>
  This can be very helpful for locating specific waypoints (i.e. using the position filter)
  in more than one file.
</para>
<example xml:id="unicsv_filename">
  <title>Example for unicsv filename option to write filenames of input formats.</title>
  <para>
    The next example ...
    <userinput>
      gpsbabel -i gpx -f file1.gpx -i gdb -f file2.gdb -o unicsv,filename=1 -F result.txt
    </userinput>
    ... could produce following output:
    <simplelist type="vert">
      <member>No,Latitude,Longitude,Name,Date,Time,Filename</member>
      <member>1,51.075139,12.463689,"578",2005/04/26,16:27:23,"reference/gdb-sample.gdb"</member>
      <member>2,51.081104,12.465277,"579",2005/04/26,16:27:23,"reference/gdb-sample.gdb"</member>
      <member>3,50.844126,12.408757,"580",2005/02/26,10:10:47,"reference/gdb-sample.gpx"</member>
      <member>4,50.654763,12.204957,"581",2005/02/26,09:57:04,"reference/gdb-sample.gpx"</member>
    </simplelist>
  </para>
</example>
