All function calls end with a return message. The return value indicates successful completion or informs the user globally that an error has occurred. You can obtain detailed information by calling the function with optional parameter errorinfo. Immediately after an error has occurred, the structure ft_err contains error messages with which you can program corresponding error handling procedures.
In Windows, the ft_err structure is defined in the header file ...\openFT\include\ftapi.h.
In Unix systems, the ft_err structure is defined in the header file /usr/include/ftapi.h.
ft_err
The structure ft_err is set up as follows:
struct ft_err
{
long main; /* output */
long detail; /* output */
long additional; /* output */
};
The fields of the structure ft_err have the following meanings:
main | Contains the error class, e.g. parameter error, internal error. |
detail | Describes the error, e.g. invalid parameter value. |
additional | Contains additional error information, e.g. which parameter is invalid. |
The error codes are described in the chapter “Error codes”.