Procedure

     DAFHLU ( DAF, handle to logical unit )

     ENTRY DAFHLU ( HANDLE, UNIT )

Abstract

     Return the logical unit associated with a handle.

Required_Reading

     DAF

Keywords

     CONVERSION
     DAF
     FILES

Declarations

    INTEGER               HANDLE
    INTEGER               UNIT

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     HANDLE     I   Handle of a DAF file.
     UNIT       O   Corresponding logical unit.

Detailed_Input

     HANDLE   is the handle associated with a previously opened
              DAF file.

Detailed_Output

     UNIT     is the Fortran logical unit to which the file is
              connected.

Parameters

     None.

Exceptions

     1)  If any error occurs while attempting to fetch a logical unit,
         the error is signaled by a routine in the call tree of this
         routine. The value of UNIT in this case is undefined.

Files

     None.

Particulars

     The best reason for knowing the logical unit to which a DAF
     is connected is to read or write from the records reserved in a
     file. Since these records are by definition invisible to the DAF
     routines, you must read and write them directly.

Examples

     In the following code fragment, the first reserved record in
     a newly created DAF is used to store the name and address
     of the person who created it.

        FTYPE = 'TEST'
        CALL DAFONW ( FNAME, FTYPE, 3, 6, IFNAME, 5, HANDLE )
        CALL DAFHLU ( HANDLE, UNIT )

        WRITE (UNIT,REC=2) 'Ellis Wyatt, JPL ',
       .                   '4800 Oak Grove Drive ',
       .                   'Room 301-125A ',
       .                   'Pasadena, CA 91109'

Restrictions

     1)  This routine may only be used to retrieve logical units
         for DAFs loaded or created using the interfaces available
         in this entry point umbrella. Using this entry point to
         retrieve units for files not loaded through these interfaces
         may result in unexpected behavior.

Literature_References

     None.

Author_and_Institution

     N.J. Bachman       (JPL)
     J. Diaz del Rio    (ODC Space)
     K.R. Gehringer     (JPL)
     H.A. Neilan        (JPL)
     W.L. Taber         (JPL)
     F.S. Turner        (JPL)
     I.M. Underwood     (JPL)
     E.D. Wright        (JPL)

Version

    SPICELIB Version 8.0.2, 25-NOV-2021 (JDR)

        Edited the header to comply with NAIF standard.

    SPICELIB Version 8.0.1, 10-OCT-2012 (EDW)

        Corrected ordering of header section.

        Removed the obsolete Reference citation to "NAIF
        Document 167.0."

    SPICELIB Version 8.0.0, 13-NOV-2001 (FST)

        This routine was updated to utilize the new handle manager
        software to manage binary file formats and consolidated
        I/O code.

    SPICELIB Version 7.0.4, 08-OCT-1999 (WLT)

        The environment lines were expanded so that the supported
        environments are now explicitly given. New
        environments are WIN-NT

    SPICELIB Version 7.0.3, 16-SEP-1999 (NJB)

        CSPICE environments were added. Some typos were corrected.

    SPICELIB Version 7.0.2, 28-JUL-1999 (WLT)

        The environment lines were expanded so that the supported
        environments are now explicitly given. New
        environments are PC-DIGITAL, SGI-O32 and SGI-N32.

    SPICELIB Version 7.0.1, 17-MAR-1999 (WLT)

        The environment lines were expanded so that the supported
        environments are now explicitly given. Previously,
        environments such as SUN-SUNOS and SUN-SOLARIS were implied
        by the environment label SUN.

    SPICELIB Version 1.0.3, 29-SEP-1993 (KRG)

        Removed references to specific DAF file open routines in the
        $Detailed_Input section of the header. This was done in order
        to minimize documentation changes if these open routines ever
        change.

        Changed the example to use the new entry point DAFONW.

    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 (IMU)