 for a description of the 
   effect of this routine. 
 </PRE>
<h4><a name="Parameters">Parameters</a></h4>
<PRE>
 
   None. 
 </PRE>
<h4><a name="Exceptions">Exceptions</a></h4>
<PRE>
 
   1)  If handle is invalid, the error will be diagnosed by routines 
       called by this routine.  The file will not be modified. 
 
   2)  If segno is out of range, the error SPICE(INVALIDINDEX) 
       will be signalled.  The file will not be modified. 
 
   3)  If recno is out of range, the error SPICE(INVALIDINDEX) 
