gd_native_type(3) returns the native data type of a field in a dirfile

SYNOPSIS

#include <getdata.h>
gd_type_t gd_native_type(DIRFILE *dirfile, const char *field_code);

DESCRIPTION

The gd_native_type() function queries a dirfile(5) database specified by dirfile and returns the native data type of the field field_code, which may contain a representation suffix.

The dirfile argument must point to a valid DIRFILE object previously created by a call to gd_open(3).

The native data type of a field of a given entry type is calculated as:

BIT or INDEX Entry:
GD_UINT64;
CONST or CARRAY Entry:
the data type of the field;
LINCOM or POLYNOM Entry:
if any of the scalar parameters is complex valued, or if the native data type of any of the input fields is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64;
LINTERP Entry:
if the look-up table is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64;
MPLEX or WINDOW Entry:
the native data type of the data field;
MULTIPLY or DIVIDE Entry:
if either input field is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64;
PHASE Entry:
the native data type of the input field;
RAW Entry:
the data type of the raw data on disk;
RECIP Entry:
if the dividend or the native data type of the input field is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64;
SARRAY or STRING Entry:
GD_STRING;
SBIT Entry:
GD_INT64.

Furthermore, if the supplied field_code contains a representation suffix, and the native data type of the field is complex valued, the native type returned will be the corresponding real valued type.

RETURN VALUE

Upon successful completion, gd_native_type() returns the native data type of the field code specified. This will be one of the symbols:
GD_UINT8, GD_INT8, GD_UINT16, GD_INT16, GD_UINT32, GD_INT32, GD_FLOAT32, GD_FLOAT64, GD_COMPLEX64, GD_COMPLEX128, GD_STRING.

The meanings of these symbols are explained in the gd_getdata(3) manual page. On error, it returns GD_UNKNOWN and sets the dirfile error to a non-zero error value. Possible error values are:

GD_E_ALLOC
The library was unable to allocate memory.
GD_E_BAD_CODE
The field specified by field_code or one of the fields it uses as input was not found in the database.
GD_E_BAD_DIRFILE
The supplied dirfile was invalid.
GD_E_DIMENSION
A scalar field was found where a vector field was expected.
GD_E_IO
An error occurred while trying to read a LINTERP table from disk.
GD_E_LUT
A LINTERP table was malformed.
GD_E_RECURSE_LEVEL
Too many levels of recursion were encountered while trying to resolve field_code. This usually indicates a circular dependency in field specification in the dirfile.

The dirfile error may be retrieved by calling gd_error(3). A descriptive error string for the last error encountered can be obtained from a call to gd_error_string(3).