Procedure

     SPKLEF ( S/P Kernel, Load ephemeris file )

     ENTRY SPKLEF ( FNAME, HANDLE )

Abstract

     Load an ephemeris file for use by the readers. Return that file's
     handle, to be used by other SPK routines to refer to the file.

Required_Reading

     SPK

Keywords

     EPHEMERIS
     FILES

Declarations

    CHARACTER*(*)         FNAME
    INTEGER               HANDLE

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     FNAME      I   Name of the file to be loaded.
     HANDLE     O   Loaded file's handle.
     FTSIZE     P   Maximum number of loaded SPK files.

Detailed_Input

     FNAME    is a string containing the name of the file to be loaded.

Detailed_Output

     HANDLE   is an integer handle assigned to the file upon loading.
              Almost every other SPK routine will subsequently use this
              number to refer to the file.

Parameters

     FTSIZE   is the maximum number of SPK files that may
              be loaded simultaneously under any circumstances.
              FTSIZE is currently set to match the maximum number
              of DAF files that may be loaded simultaneously.

Exceptions

     1)  If an attempt is made to open more DAF files than is specified
         by the parameter FTSIZE in DAFAH, an error is signaled by a
         routine in the call tree of this routine.

     2)  If an attempt is made to load more files than is specified by
         the local parameter FTSIZE, and if the DAF system has room to
         load another file, the error SPICE(SPKFILETABLEFULL) is
         signaled. The current setting of FTSIZE does not allow this
         situation to arise: the DAF system will trap the error before
         this routine has the chance.

Files

     A file specified by FNAME, to be loaded. The file is assigned a
     handle by SPKLEF, which will be used by most other routines to
     refer to it.

Particulars

     If there is room for a new file in the file table, SPKLEF creates
     an entry for it and loads the file for reading using DAFOPR.

Examples

     See $Examples in SPKBSR.

Restrictions

     None.

Literature_References

     None.

Author_and_Institution

     N.J. Bachman       (JPL)
     J. Diaz del Rio    (ODC Space)
     J.M. Lynch         (JPL)
     H.A. Neilan        (JPL)
     W.L. Taber         (JPL)
     R.E. Thurman       (JPL)

Version

    SPICELIB Version 5.0.2, 17-JUN-2021 (JDR)

        Edited the header to comply with NAIF standard.

    SPICELIB Version 5.0.1, 15-MAR-2017 (NJB)

        Corrected various spelling errors within comments.

    SPICELIB Version 5.0.0, 17-MAR-2014 (NJB)

        Updated segment pool initialization condition in entry
        point SPKLEF so that the pool is initialized only if the file
        table is empty.

    SPICELIB Version 4.0.0, 28-DEC-2001 (NJB)

        Bug fixes:

        1) When an already loaded kernel is opened with DAFOPR,
           it now has its link count reset to 1 via a call to
           DAFCLS.

        2) This routine now resets all file numbers when
           the next file number reaches INTMAX()-1, thereby avoiding
           arithmetic overflow. The numbers in the file table
           are replaced with consecutive integers in the range
           1 : NFT, such that the ordering of the numbers is not
           changed. The HFS and LFS arrays are updated accordingly.

        Also, the flags indicating validity of the re-use intervals
        are set to .FALSE. here.


    SPICELIB Version 2.0.0, 25-NOV-1992 (JML)

        When loading a file, SPKLEF now checks if the file table is
        full only after determining that the file is not currently
        loaded. Previously, if the file table was full and an attempt
        was made to reload a file, an error was signaled. A new
        exception was added as a result of this change.

        A bug in the way that SPKLEF and SPKUEF clean up the body
        tables after a file is unloaded was fixed.

    SPICELIB Version 1.0.2, 10-MAR-1992 (WLT)

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

    SPICELIB Version 1.0.1, 22-MAR-1990 (HAN)

        Literature references added to the header.

    SPICELIB Version 1.0.0, 31-JAN-1990 (RET)