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Delete a specified record from a specified E-kernel segment.
EK
Variable I/O Description -------- --- -------------------------------------------------- handle I File handle. segno I Segment number. recno I Record number.
handle is a file handle of an EK open for write access. segno is the number of the segment to which the record is to be added. EK segment numbers range from zero to N-1, where N is the number of segments in the kernel. recno is the index of the record to delete. recno must be in the range 0 : N, where N is the number of records in the segment prior to the insertion.
None. See the $Particulars section for a description of the effect of this routine.
None.
This routine operates by side effects: it deletes a record from an EK segment. Deleting a record implies: 1) All column entries in the record are deleted. 2) Link counts are decremented for data pages containing column entries in the record to be deleted. Pages whose link counts drop to zero are freed. 3) All column indexes are updated for the parent segment. 4) The link count is decremented for the page containing the record pointer structure of the record to be deleted. If the link count drops to zero, the page is freed. 5) The pointer to the deleted record is deleted from the record tree for the parent segment. 6) The segment's metadata is updated to reflect the new record count.
1) Suppose the second segment of an EK file designated by handle contains 5 records: +-----------------+ | Record 0 | +-----------------+ | Record 1 | +-----------------+ | Record 2 | +-----------------+ | Record 3 | +-----------------+ | Record 4 | +-----------------+ Then the call ekdelr_c ( handle, 1, 2 ) deletes the third record from the segment, leaving the segment's contents as follows: +-----------------+ | Record 0 | +-----------------+ | Record 1 | +-----------------+ | Record 3 | +-----------------+ | Record 4 | +-----------------+
None.
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) will be signalled. The file will not be modified. 4) If an I/O error occurs while reading or writing the indicated file, the error will be diagnosed by routines called by this routine. The file may be corrupted.
See the EK Required Reading for a discussion of the EK file format.
N.J. Bachman (JPL)
None.
-CSPICE Version 1.0.0, 16-JUN-2000 (NJB)
delete record from an EK segment