/*

-Procedure dafbbs_c ( DAF, begin backward search )

-Abstract
 
   Begin a backward search for arrays in a DAF. 
 
-Disclaimer

   THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE
   CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S.
   GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE
   ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE
   PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS"
   TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY
   WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A
   PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC
   SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE
   SOFTWARE AND RELATED MATERIALS, HOWEVER USED.

   IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA
   BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT
   LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND,
   INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS,
   REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE
   REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY.

   RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF
   THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY
   CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE
   ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE.

-Required_Reading
 
   DAF 
 
-Keywords
 
   FILES 
 
*/

   #include "SpiceUsr.h"
   #include "SpiceZfc.h"

   void dafbbs_c ( SpiceInt handle ) 

/*

-Brief_I/O
 
   Variable  I/O  Description 
   --------  ---  -------------------------------------------------- 
   handle     I   Handle of DAF to be searched. 
 
-Detailed_Input
 
   handle      is the handle of a DAF on which a backward 
               search is to be conducted. 
 
-Detailed_Output
 
   None. 
 
-Parameters
 
   None. 
 
-Files
 
   See argument handle. 
 
-Exceptions
 
   1)  If the input handle is invalid, the error will be diagnosed 
       by routines called by this routine. 
 
-Particulars
 
 
   The DAF search routines are:
   
      dafbfs_c       Begin forward search.
      daffna         Find next array.

      dafbbs_c       Begin backward search.
      daffpa_c       Find previous array.

      dafgs_c        Get summary.
      dafgn_c        Get name.
      dafgh_c        Get handle.

      dafcs_c        Continue search.

   The main function of these entry points is to allow the
   contents of any DAF to be examined on an array-by-array
   basis.

   Conceptually, the arrays in a DAF form a doubly linked list,
   which can be searched in either of two directions: forward or
   backward. It is possible to search multiple DAFs simultaneously.

   dafbfs_c (begin forward search) and daffna are used to search the
   arrays in a DAF in forward order.  In applications that search a
   single DAF at a time, the normal usage is

      dafbfs_c ( handle );
      daffna_c ( &found );

      while ( found )
      {
         dafgs_c ( sum  );
         dafgn_c ( name );
          .
          .

         daffna_c ( &found );
      }


   dafbbs_c (begin backward search) and daffpa_c are used to search the
   arrays in a DAF in backward order.  In applications that search
   a single DAF at a time, the normal usage is

      dafbbs_c ( handle );
      daffpa_c ( &found );

      while ( found )
      {
         dafgs_c ( sum  );
         dafgn_c ( name );
          .
          .

         daffpa_c ( &found );
      }


   In applications that conduct multiple searches simultaneously,
   the above usage must be modified to specify the handle of the
   file to operate on, in any case where the file may not be the
   last one specified by dafbfs_c or dafbbs_c.  The routine dafcs_c
   (DAF, continue search) is used for this purpose.  Below, we
   give an example of an interleaved search of two files specified
   by the handles handl1 and handl2.  The directions of searches
   in different DAFs are independent; here we conduct a forward
   search on one file and a backward search on the other.
   Throughout, we use dafcs to specify which file to operate on,
   before calling daffna_c, daffpa_c, dafgs_c, or dafgn_c.


      dafbfs_c ( handl1 );
      dafbbs_c ( handl2 );

      dafcs_c  ( handl1  );
      daffna_c ( &found1 );

      dafcs_c  ( handl2  );
      daffpa_c ( &found2 );

      while ( found1 || found2 )
      {
         if ( found1 )  
         {
            dafcs_c ( handl1 );
            dafgs_c ( sum    );
            dafgn_c ( name   );
             .
             .
            dafcs_c  ( &handl1 );
            daffna_c ( &found1 );
         }

         if ( found2 )  
         {
            dafcs_c ( handl2 );
            dafgs_c ( sum    );
            dafgn_c ( name   );
             .
             .
            dafcs_c  ( handl2  );
            daffpa_c ( &found2 );
         }
      }


   At any time, the latest array found (whether by daffna_c or daffpa_c)
   is regarded as the "current" array for the file in which the
   array was found.  The last DAF in which a search was started,
   executed, or continued by any of dafbfs_c, dafbbs_c, daffna_c, 
   daffpa_c or dafcs_c is regarded as the "current" DAF.  The summary 
   and name for the current array in the current DAF can be obtained
   separately, as shown above, by calls to DAFGS (get summary) and
   dafgn_c (get name).  The handle of the current DAF can also be
   obtained by calling dafgh_c (get handle).

   Once a search has been begun, it may be continued in either
   direction. That is, daffpa_c may be used to back up during a
   forward search, and daffna_c may be used to advance during a
   backward search.
 
-Examples
 
   1) See Particulars. 
 
-Restrictions
 
   None. 
 
-Literature_References
 
   NAIF Document 167.0, "Double Precision Array Files (DAF) 
   Specification and User's Guide" 
 
-Author_and_Institution
 
   N.J. Bachman    (JPL) 
   W.L. Taber      (JPL) 
   I.M. Underwood  (JPL) 
 
-Version
 
   -CSPICE Version 1.0.0, 31-JUL-1999 (NJB) (WLT) (IMU)

-Index_Entries
 
   begin daf backward search 
 
-&
*/

{ /* Begin dafbbs_c */

   /*
   Participate in error tracing.
   */
   chkin_c ( "dafbbs_c" );


   dafbbs_ ( ( integer * ) &handle );
   

   chkout_c ( "dafbbs_c" );

} /* End dafbbs_c */
