Procedure

     DASACR ( DAS, add comment records )

     SUBROUTINE DASACR ( HANDLE, N )

Abstract

     Increase the size of the comment area in a DAS file to accommodate
     a specified number of additional comment records.

Required_Reading

     DAS

Keywords

     DAS
     FILES
     UTILITY

Declarations

     IMPLICIT NONE

     INTEGER               HANDLE
     INTEGER               N

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     HANDLE     I   A DAS file handle.
     N          I   Number of comment records to append to the comment
                    area of the specified file.

Detailed_Input

     HANDLE   is the handle of an existing DAS file opened for
              comment area modification by DASOPC.

     N        is the number of records to append to the comment
              area. If NCOMR is the number of comment records
              present in the file on input, then on output the
              number of comment records will be NCOMR + N.

Detailed_Output

     None. See $Particulars for a description of the effect of this
     routine.

Parameters

     None.

Exceptions

     1)  If the input handle is invalid, an error is signaled by a
         routine in the call tree of this routine.

     2)  If an I/O error occurs during the addition process, the error
         is signaled by a routine in the call tree of this routine. The
         DAS file will probably be corrupted in this case.

Files

     See the description of the argument HANDLE in $Detailed_Input.

Particulars

     This routine is used to create space in the comment area of a DAS
     file to allow addition of comments to the file. If there are
     comment records present in the file at the time this routine is
     called, the number of comment records specified by the input
     argument N will be appended to the existing comment records.
     In any case, any existing directory records and data records will
     be shifted down by N records.

     This routine updates the file record of the specified DAS file
     to reflect the addition of records to the file's comment area.
     Also, the file summary obtainable from DASHFS will be updated to
     reflect the addition of comment records.

     This routine may be used only on existing DAS files opened by
     DASOPW.

     The association of DAS logical addresses and data within the
     specified file will remain unaffected by use of this routine.

     Normally, SPICELIB applications will not call this routine
     directly, but will add comments by calling DASAC.

     This routine has an inverse DASRCR, which removes a specified
     number of records from the end of the comment area.

Examples

     1)  Make room for 10 comment records in the comment area of a
         new DAS file.

            C
            C     Create a new DAS file.
            C
                  CALL DASOPW ( DAS, HANDLE )

            C
            C     Now add 10 comment records to the comment area.
            C
                  CALL DASACR ( HANDLE, 10 )

Restrictions

     1)  The DAS file must have a binary file format native to the host
         system.

Literature_References

     None.

Author_and_Institution

     N.J. Bachman       (JPL)
     J. Diaz del Rio    (ODC Space)
     W.L. Taber         (JPL)

Version

    SPICELIB Version 1.3.0, 13-AUG-2021 (JDR)

        Added IMPLICIT NONE statement.

        Edited the header to comply with NAIF standard.

    SPICELIB Version 1.2.0, 05-FEB-2015 (NJB)

        Updated to support integration with the handle
        manager subsystem.

        Cleaned up use of unnecessary variables and unneeded
        declarations.

    SPICELIB Version 1.1.0, 11-OCT-1996 (NJB)

        Bug fix: backward and forward directory record pointers
        are now updated when directory records are moved.

    SPICELIB Version 1.0.0, 01-FEB-1993 (NJB) (WLT)