Procedure

   dafdc_c ( DAF delete comments ) 

   void dafdc_c ( SpiceInt handle )

Abstract

   Delete the entire comment area of a specified DAF file.

Required_Reading

   DAF

Keywords

   None.

Brief_I/O

   VARIABLE  I/O  DESCRIPTION
   --------  ---  --------------------------------------------------
   handle     I   The handle of a binary DAF opened for writing.

Detailed_Input

   handle      is the handle of a binary DAF that is to have its entire
               comment area deleted. The DAF must have been opened
               with write access.

Detailed_Output

   None.

Parameters

   None.

Exceptions

   1)  If the binary DAF attached to `handle' is not open with write
       access, an error is signaled by a routine in the call tree of
       this routine.

Files

   See argument `handle' in -Detailed_Input.

Particulars

   A binary DAF contains an area which is reserved for storing
   annotations or descriptive textual information about the data
   contained in a file. This area is referred to as the "comment
   area" of the file. The comment area of a DAF is a line oriented
   medium for storing textual information. The comment area preserves
   any leading or embedded white space in the line(s) of text which are
   stored, so that the appearance of the of information will be
   unchanged when it is retrieved (extracted) at some other time.
   Trailing blanks, however, are NOT preserved, due to the way that
   character strings are represented in standard Fortran 77.

   This routine will delete the entire comment area from the binary DAF
   attached to `handle'. The size of the binary DAF will remain
   unchanged. The space that was used by the comment records is
   reclaimed: the data area of the DAF is shifted toward the beginning

Examples

   The numerical results shown for this example may differ across
   platforms. The results depend on the SPICE kernels used as
   input, the compiler and supporting libraries, and the machine
   specific arithmetic implementation.

   1) Delete the entire comment area of a DAF file. Note that this
      action should only be performed if fresh new comments are to
      be placed within the DAF file.

      Use the SPK kernel below as input DAF file for the program.

         earthstns_itrf93_201023.bsp


      Example code begins here.


      /.
         Program dafdc_ex1
      ./
      #include <stdio.h>
      #include "SpiceUsr.h"

      int main( )
      {
         /.
         Local parameters
         ./
         #define KERNEL       "earthstns_itrf93_201023.bsp"
         #define BUFFSZ       10
         #define LINLEN       1000

         /.
         Local variables.
         ./
         SpiceChar            buffer [BUFFSZ][LINLEN];

         SpiceInt             handle;
         SpiceInt             i;
         SpiceInt             n;

         SpiceBoolean         done;

         /.
         Open a DAF for write. Return a `handle' referring to the
         file.
         ./
         dafopw_c ( KERNEL, &handle );

         /.
         Print the first 10 lines of comments from the DAF file.
         ./
         printf( "Comment area of input DAF file (max. 10 lines): \n" );
         printf( "--------------------------------"
                 "------------------------------\n" );

         dafec_c ( handle, BUFFSZ, LINLEN, &n, buffer, &done );

         for ( i = 0; i < n; i++ )
         {
            printf( "%s\n", buffer[i] );
         }

         printf( "--------------------------------"
                 "------------------------------\n" );
         printf( " \n" );
         printf( "Deleting entire comment area...\n" );

         /.
         Delete all the comments from the DAF file.
         ./
         dafdc_c ( handle );

         /.
         Close the DAF file and re-open it for read
         access to work around the dafec_c restriction
         on comments not to be modified while they are
         being extracted.
         ./
         dafcls_c ( handle );

         dafopr_c ( KERNEL, &handle );

         /.
         Check if the comments have indeed been deleted.
         ./
         dafec_c ( handle, BUFFSZ, LINLEN, &n, buffer, &done );

         if ( done  &&  ( n == 0 ) )
         {
            printf( " \n" );
            printf( "   Successful operation.\n" );
         }
         else
         {
            printf( " \n" );
            printf( "   Operation failed.\n" );
         }

         /.
         Safely close the DAF.
         ./
         dafcls_c ( handle );

         return ( 0 );
      }


      When this program was executed on a Mac/Intel/cc/64-bit
      platform, the output was:


      Comment area of input DAF file (max. 10 lines):
      --------------------------------------------------------------

         SPK for DSN Station Locations
         =====================================================================

         Original file name:                   earthstns_itrf93_201023.bsp
         Creation date:                        2020 October 28 12:30
         Created by:                           Nat Bachman  (NAIF/JPL)


         Introduction
      --------------------------------------------------------------

      Deleting entire comment area...

         Successful operation.

Restrictions

   None.

Literature_References

   None.

Author_and_Institution

   N.J. Bachman        (JPL)
   J. Diaz del Rio     (ODC Space)
   K.R. Gehringer      (JPL)

Version

   -CSPICE Version 1.0.1, 25-NOV-2021 (JDR)

       Edited the header to comply with NAIF standard. Added complete
       code example.

   -CSPICE Version 1.0.0, 16-NOV-2006 (NJB) (KRG)

Index_Entries

   delete DAF comment area