NAME

dirfile_validate --- check a dirfile field code for validity

SYNOPSIS

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

DESCRIPTION

The dirfile_validate() function queries a dirfile(5) database specified by dirfile and checks whether field_code, which may contain a representation suffix, specifies a valid field.

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

This function checks whether the field and its input fields (if any) are found, whether the representation suffix (if any) is valid, and also that all non-literal scalar parameters specify valid CONST fields.

RETURN VALUE

If all checks pass, dirfile_validate() returns zero. On error, it returns -1 and sets the dirfile error to a non-zero error value. Possible error values are:
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_BAD_REPR
The representation suffix specified in field_code was not recognised.
GD_E_BAD_SCALAR
A non-literal scalar used in the definition of the field or one of its inputs was not found, or was not a CONST field.
GD_E_DIMENSION
A scalar field was found where a vector field was expected.
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 get_error(3). A descriptive error string for the last error encountered can be obtained from a call to get_error_string(3).

NOTES

It is not necessary to call this function before passing a field code to another GetData function: all functions which accept field codes perform these checks themselves.

SEE ALSO

dirfile(5), dirfile_open(3), getdata(3), get_error(3), get_error_string(3)