Procedure

     SPCDC ( SPK and CK, delete comments )

     SUBROUTINE SPCDC ( HANDLE )

Abstract

     Empty the comment area of a binary SPK or CK file.

Required_Reading

     SPC

Keywords

     FILES

Declarations

     IMPLICIT NONE

     INTEGER               HANDLE

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     HANDLE     I   Handle assigned to binary SPK or CK file.

Detailed_Input

     HANDLE   is the handle assigned to the binary SPK or CK file
              which has been opened for write access.

              Use the SPICELIB routine DAFOPW to open the file for
              write access and get HANDLE. Upon exit, this binary file
              will have an empty comment area: all previous comments
              are deleted. Note, however, that the size of the file
              does not change.

Detailed_Output

     None.

Parameters

     None.

Exceptions

     1)  If the file does not contain any comments in its comment area
         on input, it will be unchanged by this routine.

Files

     See argument HANDLE.

Particulars

     The structure of SPK and CK files accommodates comments in
     addition to data. The following three routines are available
     for accessing the comment area of a binary SPK or CK file:

           SPCAC           add comments

           SPCEC           extract comments

           SPCDC           delete comments

     Note that comments must consist of only text, that is, printable
     ASCII characters, specifically ASCII 32-126. This excludes
     tabs (ASCII 9) and control characters.

     The SPC conversion routines---SPCB2A, SPCA2B, SPCB2T, and
     SPCT2B---include these comments when converting SPK and CK
     files between binary and text formats.

Examples

     1)  Suppose we have a binary SPK file called A.BSP. The following
         code fragment deletes any comments that may have been stored
         in the comment area of the file.

                 CALL DAFOPW ( 'A.BSP', HANDLE )

                 CALL SPCDC  ( HANDLE )

     2)  Suppose B.BSP is a binary SPK file with comments in its
         comment area. The routine TXTOPN opens a new text file.

           C
           C     Open the binary SPK file with write access and
           C     get its handle.
           C
                 CALL DAFOPW ( 'B.BSP', HANDLE )

           C
           C     Open a new text file and write the comments
           C     from the SPK file to it.
           C
                 CALL TXTOPN ( 'COMMENTS.TXT',   UNIT1 )
                 CALL SPCEC  ( HANDLE,           UNIT1 )

           C
           C     Delete the comments in the SPK file.
           C
                 CALL SPCDC  ( HANDLE )

           C
           C     Open another new text file and try to write
           C     comments from the SPK file to it.
           C
                 CALL TXTOPN ( 'NOCOMMENTS.TXT', UNIT2 )
                 CALL SPCEC  ( HANDLE,           UNIT2 )

         After executing this code fragment, COMMENTS.TXT would
         contain the comments from the SPK file.  NOCOMMENTS.TXT
         would be empty because of the call to SPCDC.

Restrictions

     None.

Literature_References

     None.

Author_and_Institution

     J. Diaz del Rio    (ODC Space)
     J.E. McLean        (JPL)
     W.L. Taber         (JPL)

Version

    SPICELIB Version 1.1.0, 03-JUN-2021 (JDR)

        Added IMPLICIT NONE statement.

        Edited the header to comply with NAIF standard.

        Moved the contents of the $Files section to the description of
        HANDLE in $Detailed_Input section, and referred to it from
        $Files.

    SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)

        Comment section for permuted index source lines was added
        following the header.

    SPICELIB Version 1.0.0, 05-APR-1991 (JEM)