<para>
This option tells GPSBabel whether to read (on input) or write (on output)
GPRMC sentences.  The default is to read or write GPRMC sentences.  To
disable GPRMC sentences, specify <option>gprmc=0</option>.
</para>
<para>
GPRMC sentences contain the "recommended minimum" positional information,
including date and time, heading, and velocity.  Note that they do not
include altitude.  For altitude, you will have to include GPGGA sentences.
</para>
