SDK Include File

The include file "lianja_api.h" contains definitions of variable types, data structures and macro synonyms which are used by many of the API functions.

API Variable Types

TYPE NAME	USED FOR	DATATYPE
API_ATYPE	Array variable	int (512)
API_BOTTOM	DBF_GOTO( API_BOTTOM )	int (-2)
API_CLASS	User defined class (UDC)	int (1)
API_CTYPE	Character variable	int (1)
API_DTYPE	Date variable	int (8)
API_FUNCTION	User defined function (UDF)	int (0)
API_LTYPE	Logical variable	int (4)
API_NTYPE	Numeric variable	int (2)
API_OTYPE	Object variable	int (256)
API_PRIVATE	Private memory variable	int (1)
API_PUBLIC	Public memory variable	int (1)
API_REFPAR	Passed by reference with @	int (32)
API_TOP	DBF_GOTO( API_TOP )	int (-1)
API_TTYPE	DateTime variable	int (64)
API_UTYPE	Undefined variable	int (0)
API_YTYPE	Currency variable	int (128)
CHARACTER	Character string	char
CURRENCY	Currency	Currency structure
DATE	Date	unsigned long
DATETIME	Datetime	DateTime structure
LOGICAL	Logical data type	int
MEMO	Memo	Operating system dependant
NUMERIC	Numeric data type	double
OBJARG	Object argument	Object argument format
OBJECT	Object	Pointer to an object

API Data Structures

The LIANJA_EXTENSION_TABLE data structure below is used to store information relating the C UDF or UDC to its name within Lianja. This structure is used when dynamically loading in the function or class.

struct	LIANJA_EXTENSION_TABLE {
	char			*name;				/* Pointer to Lianja function name		*/
	char			*apiname;			/* Pointer to C support function name	*/
	int			type;				/* Function type 0 function 1 class		*/
};

The API_EXPRESSION_RESULT data structure below is used to store the result which is returned from the api_expression() function.

struct	API_EXPRESSION {
	int			errno;				/* Error() number			*/
	char			type;				/* Data type of result				*/
	int			width;				/* Width of result					*/
	int			decimal;				/* Decimal places					*/
	char			character;			/* CHARACTER result				*/
	double 		number;				/* NUMERIC RESULT				*/
	char			logical;				/* LOGICAL result					*/
	unsigned long	date;				/* DATE result				*/
	DATETIME 	datetime;			/* DATETIME result					*/
	CURRENCY 	currency;			/* CURRENCY result					*/
};

The API_MEMVAR data structure below is used to describe the contents of a memory variable.

union	API_UNION {
	char			*info_character;		/* Char memory variable				*/
	char			info_logical;			/* Logical memory variable			*/
	double		info_number;			/* Numeric memory variable			*/
	unsigned long	info_date;			/* Date memory variable				*/
	DATETIME	info_datetime;	 	/* DateTime memory variable			*/
	CURRENCY	info_currency;		/* Currency memory variable			*/
};

struct	API_MEMVAR {
	char			type;				/* Data type of the memory			*/
	union		API_UNION value;	/* Value of the memory variable		*/
	int			width;				/* Display width					*/
	int			decimal;				/* Display # of decimal places			*/
};

The API_FIELD data structure is used to describe the structure of a field.

struct	API_FIELD {
    int			fieldno;				/* Field number					*/
    char		type;				/* Data type of field					*/
    int			size;				/* Storage size in the record			*/
    int			width;				/* Display width					*/
    int 			decimal;				/* # decimal places for numerics		*/
    char		*value;				/* Pointer to data in current record		*/
};