/*

-Procedure getfvn_c (Get instrument FOV parameters, by instrument name)

-Abstract

   Return the field-of-view (FOV) parameters for a specified
   instrument. The instrument is specified by name.

-Disclaimer

   THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE
   CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S.
   GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE
   ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE
   PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS"
   TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY
   WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A
   PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC
   SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE
   SOFTWARE AND RELATED MATERIALS, HOWEVER USED.

   IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA
   BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT
   LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND,
   INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS,
   REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE
   REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY.

   RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF
   THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY
   CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE
   ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE.

-Required_Reading

   NAIF_IDS

-Keywords

   FOV
   INSTRUMENT

*/
   #include "SpiceUsr.h"
   #include "SpiceZfc.h"
   #include "SpiceZmc.h"
   #include "SpiceZst.h"

   void getfvn_c ( ConstSpiceChar    * inst,
                   SpiceInt            room,
                   SpiceInt            shalen,
                   SpiceInt            fralen,
                   SpiceChar         * shape,
                   SpiceChar         * frame,
                   SpiceDouble         bsight [3],
                   SpiceInt          * n,
                   SpiceDouble         bounds [][3] )

/*

-Brief_I/O

   VARIABLE  I/O  DESCRIPTION
   --------  ---  --------------------------------------------------
   inst       I   Name of an instrument.
   room       I   Maximum number of vectors that can be returned.
   shalen     I   Maximum length of output string `shape'.
   fralen     I   Maximum length of output string `frame'.
   shape      O   Instrument FOV shape.
   frame      O   Name of the frame in which FOV vectors are defined.
   bsight     O   Boresight vector.
   n          O   Number of boundary vectors returned.
   bounds     O   FOV boundary vectors.

-Detailed_Input

   inst        is the name of an instrument, such as a
               spacecraft-mounted framing camera, for which the field of
               view parameters are to be retrieved from the kernel pool.
               `inst' is case-insensitive, and leading and trailing blanks
               in `inst' are not significant. Optionally, you may supply
               the integer ID for the instrument as an integer string.
               For example, both "CASSINI_ISS_NAC" and "-82360" are
               legitimate strings that indicate the CASSINI ISS NAC
               camera is the instrument of interest.

   room        is the maximum number of 3-dimensional vectors that can
               be returned in `bounds'.

   shalen      is the maximum allowed length of the output string
               `shape'. This length must be large enough to hold the
               output string plus the null-terminator character. If the
               output string is expected to have X characters, `shalen'
               should be at least X+1.

   fralen      is the maximum allowed length of the output string
               `frame'. This length must be large enough to hold the
               output string plus the null-terminator character. If the
               output string is expected to have X characters, `fralen'
               should be at least X+1.

-Detailed_Output

   shape       is a character string that describes the "shape" of
               the field of view. Possible values returned are:

                  "POLYGON"
                  "RECTANGLE"
                  "CIRCLE"
                  "ELLIPSE"

               If the value of `shape' is "POLYGON" the field of view
               of the instrument is a pyramidal polyhedron. The
               vertex of the pyramid is at the instrument focal
               point. The rays along the edges of the pyramid are
               parallel to the vectors returned in `bounds'.

               If the value of `shape' is "RECTANGLE" the field of view
               of the instrument is a rectangular pyramid. The vertex
               of the pyramid is at the instrument focal point. The
               rays along the edges of the pyramid are parallel to
               the vectors returned in `bounds'. Moreover, in this
               case, the boresight points along the axis of symmetry
               of the rectangular pyramid.

               If the value of `shape' is "CIRCLE" the field of view of
               the instrument is a circular cone centered on the
               boresight vector. The vertex of the cone is at the
               instrument focal point. A single vector will be
               returned in `bounds'. This vector will be parallel to a
               ray that lies in the cone that makes up the boundary
               of the field of view.

               If the value of `shape' is "ELLIPSE" the field of view
               of the instrument is an elliptical cone with the
               boresight vector as the axis of the cone. In this
               case two vectors are returned in `bounds'. One of the
               vectors returned in `bounds' points to the end of the
               semi-major axis of a perpendicular cross section of
               the elliptic cone. The other vector points to the end
               of the semi-minor axis of a perpendicular cross
               section of the cone.

   frame       is the name of the reference frame in which the field
               of view boundary vectors are defined.

   bsight      is a vector representing the principal instrument view
               direction that can be

                  -  the central pixel view direction,
                  -  the optical axis direction,
                  -  the FOV geometric center view direction,
                  -  an axis of the FOV frame,

               or any other vector specified for this purpose
               in the IK FOV definition. The length of `bsight'
               is not specified other than being non-zero.

   n           is the number of boundary vectors returned.

   bounds      is an array of vectors that point to the "corners" of
               the instrument field of view. (See the discussion
               accompanying `shape' for an expansion of the term
               "corner of the field of view.") Note that the vectors
               returned in `bounds' are not necessarily unit vectors.
               Their magnitudes will be as set in the IK (for
               'CORNERS'-style FOV specifications) or the same as the
               magnitude of the boresight (for 'ANGLES'-style FOV
               specifications.)

-Parameters

   MINCOS      is the lower limit on the value of the cosine of the
               cross or reference angles in the 'ANGLES' specification
               cases. See the header of the routine getfov_c for its
               current value.

-Exceptions

   1)  If the name of the instrument cannot be translated to its NAIF
       ID code, the error SPICE(IDCODENOTFOUND) is signaled by a
       routine in the call tree of this routine.

   2)  If the frame associated with the instrument can not be found,
       an error is signaled by a routine in the call tree of this
       routine.

   3)  If the shape of the instrument field of view can not be found
       in the kernel pool, an error is signaled by a routine in the
       call tree of this routine.

   4)  If the FOV_SHAPE specified by the instrument kernel is not
       one of the four values: 'CIRCLE', 'POLYGON', 'ELLIPSE', or
       'RECTANGLE', an error is signaled by a routine in the call
       tree of this routine. If the 'ANGLES' specification is used,
       FOV_SHAPE must be one of the three values: 'CIRCLE',
       'ELLIPSE', or 'RECTANGLE'.

   5)  If the direction of the boresight cannot be located in the
       kernel pool, an error is signaled by a routine in the call
       tree of this routine.

   6)  If the number of components for the boresight vector in the
       kernel pool is not 3, or they are not numeric, an error is
       signaled by a routine in the call tree of this routine.

   7)  If the boresight vector is the zero vector, an error is 
       is signaled by a routine in the call tree of this routine.

   8)  If the 'ANGLES' specification is not present in the kernel
       pool and the boundary vectors for the edge of the field of
       view cannot be found in the kernel pool, an error is signaled
       by a routine in the call tree of this routine.

   9)  If there is insufficient room (as specified by the argument
       `room') to return all of the vectors associated with the
       boundary of the field of view, an error is signaled by a
       routine in the call tree of this routine.

   10) If the number of components of vectors making up the field of
       view is not a multiple of 3, an error is signaled by a routine
       in the call tree of this routine.

   11) If the number of components of vectors making up the field of
       view is not compatible with the shape specified for the field
       of view, an error is signaled by a routine in the call tree of
       this routine.

   12) If the reference vector for the 'ANGLES' specification can not
       be found in the kernel pool, an error is signaled by a routine
       in the call tree of this routine.

   13) If the reference vector stored in the kernel pool to support
       the 'ANGLES' specification contains an incorrect number of
       components, contains 3 character components, or is parallel to
       the boresight, an error is signaled by a routine in the call
       tree of this routine.

   14) If the 'ANGLES' specification is present in the kernel pool
       and the reference angle stored in the kernel pool to support
       the 'ANGLES' specification is absent from the kernel pool, an
       error is signaled by a routine in the call tree of this
       routine.

   15) If the keyword that stores the angular units for the angles
       used in the 'ANGLES' specification is absent from the kernel
       pool, an error is signaled by a routine in the call tree of
       this routine.

   16) If the value used for the units in the 'ANGLES' specification
       is not one of the supported angular units of convrt_c, an error
       is signaled by a routine in the call tree of this routine.

   17) If the keyword that stores the cross angle for the 'ANGLES'
       specification is needed and is absent from the kernel pool, an
       error is signaled by a routine in the call tree of this
       routine.

   18) If the angles for the 'RECTANGLE'/'ANGLES' specification case
       have cosines that are less than those stored in the parameter
       MINCOS defined in the getfov_c routine, an error is signaled by
       a routine in the call tree of this routine.

   19) If the class specification contains something other than
       'ANGLES' or 'CORNERS', an error is signaled by a routine in
       the call tree of this routine.

   20) In the event that the CLASS_SPEC keyword is absent from the
       kernel pool for the instrument whose FOV is sought, this
       module assumes the 'CORNERS' specification is to be utilized.

   21) If the `inst' input string pointer is null, the error
       SPICE(NULLPOINTER) is signaled.

   22) If the `inst' input string has zero length, the error
       SPICE(EMPTYSTRING) is signaled.

   23) If any of the `shape' or `frame' output string pointers is
       null, the error SPICE(NULLPOINTER) is signaled.

   24) If any of the `shape' or `frame' output strings has length
       less than two characters, the error SPICE(STRINGTOOSHORT) is
       signaled, since the output string is too short to contain one
       character of output data plus a null terminator.

-Files

   Appropriate SPICE kernels must be loaded by the calling program
   before this routine is called.

   This routine relies upon having successfully loaded an instrument
   kernel (IK file) via the routine furnsh_c prior to calling this
   routine.

   The name `inst' must be associated with an NAIF ID code, normally
   through a frames kernel (FK file) or instrument kernel (IK file).

   Kernel data are normally loaded via furnsh_c once per program run,
   NOT every time this routine is called.

-Particulars

   This routine provides a common interface for retrieving from the
   kernel pool the geometric characteristics of an instrument field
   of view for a wide variety of remote sensing instruments
   across many different space missions.

   This routine is identical in function to the routine getfov_c except
   that it allows you to refer to an instrument by name (via a
   character string) instead of by its NAIF instrument ID.

   Given the NAIF instrument name, (and having "loaded" the
   instrument field of view description and instrument name to NAIF
   ID mapping) this routine returns the boresight of the instrument,
   the "shape" of the field of view, a collection of vectors
   that point along the edges of the field of view, and the
   name of the reference frame in which these vectors are defined.

   Currently this routine supports two classes of specifications
   for FOV definitions: "corners" and "angles".

   The "corners" specification requires that the following keywords
   defining the shape, boresight, boundary vectors, and reference
   frame of the FOV be provided in one of the text kernel files
   (normally an IK file) loaded into the kernel pool (in the
   keywords below <INSTID> is replaced with the instrument ID which
   corresponds to the `inst' name passed into the module):

      INS<INSTID>_FOV_CLASS_SPEC         must be set to 'CORNERS' or
                                         omitted to indicate the
                                         "corners"-class
                                         specification.

      INS<INSTID>_FOV_SHAPE              must be set to one of these
                                         values:

                                            'CIRCLE'
                                            'ELLIPSE'
                                            'RECTANGLE'
                                            'POLYGON'

      INS<INSTID>_FOV_FRAME              must contain the name of
                                         the frame in which the
                                         boresight and boundary
                                         corner vectors are defined.

      INS<INSTID>_BORESIGHT              must be set to a 3D vector
                                         defining the boresight in
                                         the FOV frame specified in
                                         the FOV_FRAME keyword.

      INS<INSTID>_FOV_BOUNDARY   or
      INS<INSTID>_FOV_BOUNDARY_CORNERS   must be set to one (for
                                         FOV_SHAPE = 'CIRCLE'), two
                                         (for FOV_SHAPE =
                                         'ELLIPSE'), four (for
                                         FOV_SHAPE = 'RECTANGLE'),
                                         or three or more (for
                                         'POLYGON') 3D vectors
                                         defining the corners of the
                                         FOV in the FOV frame
                                         specified in the FOV_FRAME
                                         keyword. The vectors should
                                         be listed in either
                                         clockwise or
                                         counterclockwise order.
                                         This is required by some
                                         SPICE routines that make
                                         use of FOV specifications.

   The "angles" specification requires the following keywords
   defining the shape, boresight, reference vector, reference and
   cross angular extents of the FOV be provided in one of the text
   kernel files (normally an IK file) loaded into the kernel
   pool (in the keywords below <INSTID> is replaced with the
   instrument ID which corresponds to the `inst' name passed into the
   module):

      INS<INSTID>_FOV_CLASS_SPEC         must be set to 'ANGLES' to
                                         indicate the "angles"-class
                                         specification.

      INS<INSTID>_FOV_SHAPE              must be set to one of these
                                         values:

                                            'CIRCLE'
                                            'ELLIPSE'
                                            'RECTANGLE'

      INS<INSTID>_FOV_FRAME              must contain the name of
                                         the frame in which the
                                         boresight and the computed
                                         boundary corner vectors are
                                         defined.

      INS<INSTID>_BORESIGHT              must be set to a 3D vector
                                         defining the boresight in
                                         the FOV frame specified in
                                         the FOV_FRAME keyword.

      INS<INSTID>_FOV_REF_VECTOR         must be set to a 3D vector
                                         that together with the
                                         boresight vector defines
                                         the plane in which the
                                         first angular extent of the
                                         FOV specified in the
                                         FOV_REF_ANGLE keyword is
                                         measured.

      INS<INSTID>_FOV_REF_ANGLE          must be set to the angle
                                         that is 1/2 of the total
                                         FOV angular extent in the
                                         plane defined by the
                                         boresight and the vector
                                         specified in the
                                         FOV_REF_VECTOR keyword. The
                                         the FOV angular half-extents
                                         are measured from the
                                         boresight vector.

      INS<INSTID>_FOV_CROSS_ANGLE        must be set to the angle
                                         that is 1/2 of the total
                                         FOV angular extent in the
                                         plane containing the
                                         boresight and perpendicular
                                         to the plane defined by the
                                         boresight and the vector
                                         specified in the
                                         FOV_REF_VECTOR keyword. The
                                         the FOV angular half-extents
                                         are measured from the
                                         boresight vector. This
                                         keyword is not required for
                                         FOV_SHAPE = 'CIRCLE'.

      INS<INSTID>_FOV_ANGLE_UNITS        must specify units for the
                                         angles given in the
                                         FOV_REF_ANGLE and
                                         FOV_CROSS_ANGLE keywords.
                                         Any angular units
                                         recognized by convrt_c are
                                         acceptable.

   The INS<INSTID>_FOV_REF_ANGLE and INS<INSTID>_FOV_CROSS_ANGLE
   keywords can have any values for the 'CIRCLE' and 'ELLIPSE'
   FOV shapes but must satisfy the condition cos( angle ) > 0 for
   the 'RECTANGLE' shape.

   This routine is intended to be an intermediate level routine.
   It is expected that users of this routine will be familiar
   with the SPICE frames subsystem and will be comfortable writing
   software to further manipulate the vectors retrieved by this
   routine.

-Examples

   The numerical results shown for this example may differ across
   platforms. The results depend on the SPICE kernels used as input,
   the compiler and supporting libraries, and the machine specific
   arithmetic implementation.

   1) Load an IK, fetch the parameters for each of the FOVs defined
      within and print these parameters to the screen.

      Use the kernel shown below, an IK defining four FOVs of
      various shapes and sizes, to load the FOV definitions, and the
      mapping between their NAMES and NAIF IDs.


         KPL/IK

         File name: getfvn_ex1.ti

         The keywords below define a circular, 10-degree wide FOV
         with the boresight along the +Z axis of the 'SC999_INST001'
         frame for an instrument with ID -999001 using the
         "angles"-class specification.

         \begindata
            INS-999001_FOV_CLASS_SPEC       = 'ANGLES'
            INS-999001_FOV_SHAPE            = 'CIRCLE'
            INS-999001_FOV_FRAME            = 'SC999_INST001'
            INS-999001_BORESIGHT            = ( 0.0, 0.0, 1.0 )
            INS-999001_FOV_REF_VECTOR       = ( 1.0, 0.0, 0.0 )
            INS-999001_FOV_REF_ANGLE        = ( 5.0 )
            INS-999001_FOV_ANGLE_UNITS      = ( 'DEGREES' )
         \begintext

         The keywords below define an elliptical FOV with 2- and
         4-degree angular extents in the XZ and XY planes and the
         boresight along the +X axis of the 'SC999_INST002' frame for
         an instrument with ID -999002 using the "corners"-class
         specification.

         \begindata
            INS-999002_FOV_SHAPE            = 'ELLIPSE'
            INS-999002_FOV_FRAME            = 'SC999_INST002'
            INS-999002_BORESIGHT            = ( 1.0, 0.0, 0.0 )
            INS-999002_FOV_BOUNDARY_CORNERS = (
                                    1.0,  0.0,        0.01745506,
                                    1.0,  0.03492077, 0.0        )
         \begintext

         The keywords below define a rectangular FOV with 1.2- and
         0.2-degree angular extents in the ZX and ZY planes and the
         boresight along the +Z axis of the 'SC999_INST003' frame for
         an instrument with ID -999003 using the "angles"-class
         specification.

         \begindata
            INS-999003_FOV_CLASS_SPEC       = 'ANGLES'
            INS-999003_FOV_SHAPE            = 'RECTANGLE'
            INS-999003_FOV_FRAME            = 'SC999_INST003'
            INS-999003_BORESIGHT            = ( 0.0, 0.0, 1.0 )
            INS-999003_FOV_REF_VECTOR       = ( 1.0, 0.0, 0.0 )
            INS-999003_FOV_REF_ANGLE        = ( 0.6 )
            INS-999003_FOV_CROSS_ANGLE      = ( 0.1 )
            INS-999003_FOV_ANGLE_UNITS      = ( 'DEGREES' )
         \begintext

         The keywords below define a triangular FOV with the
         boresight along the +Y axis of the 'SC999_INST004' frame
         for an instrument with ID -999004 using the "corners"-class
         specification.

         \begindata
            INS-999004_FOV_SHAPE            = 'POLYGON'
            INS-999004_FOV_FRAME            = 'SC999_INST004'
            INS-999004_BORESIGHT            = (  0.0,  1.0,  0.0 )
            INS-999004_FOV_BOUNDARY_CORNERS = (  0.0,  0.8,  0.5,
                                                 0.4,  0.8, -0.2,
                                                -0.4,  0.8, -0.2 )
         \begintext

         The keywords below define the INSTRUMENT name to NAIF ID
         mappings for this example. For convenience we will keep them
         in the example's IK although they could be placed elsewhere
         (normally on the mission's frames kernel)

         \begindata
            NAIF_BODY_NAME += ( 'SC999_INST001' )
            NAIF_BODY_CODE += ( -999001 )

            NAIF_BODY_NAME += ( 'SC999_INST002' )
            NAIF_BODY_CODE += ( -999002 )

            NAIF_BODY_NAME += ( 'SC999_INST003' )
            NAIF_BODY_CODE += ( -999003 )

            NAIF_BODY_NAME += ( 'SC999_INST004' )
            NAIF_BODY_CODE += ( -999004 )
         \begintext

         End of IK


      Example code begins here.


      /.
         Program getfvn_ex1
      ./
      #include <stdio.h>
      #include "SpiceUsr.h"

      int main( )
      {

         /.
         Local parameters
         ./
         #define MAXBND       4
         #define NUMINS       4
         #define WDSIZE       33

         /.
         Local variables
         ./
         SpiceChar            frame  [WDSIZE];
         SpiceChar            shape  [WDSIZE];

         SpiceDouble          bounds [MAXBND][3];
         SpiceDouble          bsight [3];

         SpiceInt             i;
         SpiceInt             j;
         SpiceInt             n;

         /.
         Define the instrument IDs.
         ./
         SpiceChar            instnm [NUMINS][WDSIZE] = { "SC999_INST001",
                                                          "SC999_INST002",
                                                          "SC999_INST003",
                                                          "SC999_INST004" };

         /.
         Load the IK file.
         ./
         furnsh_c ( "getfvn_ex1.ti" );

         /.
         For each instrument ...
         ./
         printf( "--------------------------------------\n" );
         for ( i = 0; i < NUMINS; i++ )
         {

            /.
            ... fetch FOV parameters and ...
            ./
            getfvn_c ( instnm[i], MAXBND, WDSIZE,
                       WDSIZE,    shape,  frame,
                       bsight,    &n,     bounds );

            /.
            ... print them to the screen.
            ./
            printf( "Instrument NAME: %s\n", instnm[i] );
            printf( "    FOV shape: %s\n", shape );
            printf( "    FOV frame: %s\n", frame );
            printf( "FOV boresight:  %11.8f %11.8f %11.8f\n",
                              bsight[0], bsight[1], bsight[2] );

            printf( "  FOV corners:\n" );
            for ( j = 0; j < n; j++ )
            {
               printf( "                %11.8f %11.8f %11.8f\n",
                        bounds[j][0], bounds[j][1], bounds[j][2] );
            }
            printf( "--------------------------------------\n" );
         }

         return ( 0 );
      }


      When this program was executed on a Mac/Intel/cc/64-bit
      platform, the output was:


      --------------------------------------
      Instrument NAME: SC999_INST001
          FOV shape: CIRCLE
          FOV frame: SC999_INST001
      FOV boresight:   0.00000000  0.00000000  1.00000000
        FOV corners:
                       0.08715574  0.00000000  0.99619470
      --------------------------------------
      Instrument NAME: SC999_INST002
          FOV shape: ELLIPSE
          FOV frame: SC999_INST002
      FOV boresight:   1.00000000  0.00000000  0.00000000
        FOV corners:
                       1.00000000  0.00000000  0.01745506
                       1.00000000  0.03492077  0.00000000
      --------------------------------------
      Instrument NAME: SC999_INST003
          FOV shape: RECTANGLE
          FOV frame: SC999_INST003
      FOV boresight:   0.00000000  0.00000000  1.00000000
        FOV corners:
                       0.01047177  0.00174523  0.99994365
                      -0.01047177  0.00174523  0.99994365
                      -0.01047177 -0.00174523  0.99994365
                       0.01047177 -0.00174523  0.99994365
      --------------------------------------
      Instrument NAME: SC999_INST004
          FOV shape: POLYGON
          FOV frame: SC999_INST004
      FOV boresight:   0.00000000  1.00000000  0.00000000
        FOV corners:
                       0.00000000  0.80000000  0.50000000
                       0.40000000  0.80000000 -0.20000000
                      -0.40000000  0.80000000 -0.20000000
      --------------------------------------


-Restrictions

   1)  This routine will not operate unless proper mapping between
       the instrument name `inst' and a NAIF ID exists, an I-kernel for
       that instrument ID has been loaded via a call to furnsh_c prior
       to calling this routine and this IK contains the specification
       for the instrument field of view consistent with the
       expectations of this routine.

-Literature_References

   None.

-Author_and_Institution

   J. Diaz del Rio     (ODC Space)

-Version

   -CSPICE Version 1.0.0, 17-DEC-2021 (JDR)

-Index_Entries

   return instrument's FOV parameters, using instrument name

-&
*/

{ /* Begin getfvn_c */

   /*
   Participate in error tracing.
   */
   chkin_c ( "getfvn_c" );

   /*
   Check the input string `inst' to make sure the pointer is non-null
   and the string length is non-zero.
   */
   CHKFSTR ( CHK_STANDARD, "getfvn_c", inst   );

   /*
   Check the output string arguments:

      shape
      frame

   Make sure each pointer is non-null and each string has enough room
   for one output character and a null terminator.
   */
   CHKOSTR ( CHK_STANDARD, "getfvn_c", shape, shalen );
   CHKOSTR ( CHK_STANDARD, "getfvn_c", frame, fralen );

   /*
   Call the f2c'd Fortran routine.
   */
   getfvn_ (  ( char       * )  inst,
              ( integer    * ) &room,
              ( char       * )  shape,
              ( char       * )  frame,
              ( doublereal * )  bsight,
              ( integer    * )  n,
              ( doublereal * )  bounds,
              ( ftnlen       )  strlen(inst),
              ( ftnlen       )  shalen - 1,
              ( ftnlen       )  fralen - 1   );

   /*
   Convert

      shape
      frame

   to C-style strings.
   */
   if ( !failed_c() )
   {
      F2C_ConvertStr ( shalen, shape );
      F2C_ConvertStr ( fralen, frame );
   }
   else
   {
      /*
      We've already checked that there's room for a null terminator in
      each output string.
      */
      shape[0] = NULLCHAR;
      frame[0] = NULLCHAR;
   }

   chkout_c ( "getfvn_c" );

} /* End getfvn_c */
