<para>
genurl is a convenience option for generating the scaling paramaters
when accessing the Tiger servers.  It will output the latitude, longitude,
height, and width parameters in a form suitable for use in the URL to generate
a map that will hold all the points to be displayed  and is suitably scaled
and centered.   
</para>
<para>For example:</para>
<para><userinput>gpsbabel -i geo -f geocaching.loc -o tiger,genurl=tiger.ctr -F tiger.dat</userinput></para>
<para>
may create tiger.ctr with
<screen format="linespecific">
lat=36.042108&amp;lon=-86.877408&amp;ht=0.161172&amp;wid=0.591771&amp;iwd=768&amp;iht=768</screen>

After uploading tiger.dat to a public server, a request to 
<screen format="linespecific"> http://tiger.census.gov/cgi-bin/mapgen?murl=$THATFILE$(cat tiger.ctr)</screen>
will return a gif file from the tiger server that's suitably scaled.

</para>

