get_reference (3) - Linux Manuals

get_reference: retrieve or set the reference field for a dirfile

Command to display get_reference manual in Linux: $ man 3 get_reference

NAME

dirfile_reference, get_reference --- retrieve or set the reference field for a dirfile

SYNOPSIS

#include <getdata.h>

const char *dirfile_reference(DIRFILE *dirfile, const char *field_code);
const char *get_reference(DIRFILE *dirfile);

DESCRIPTION

The dirfile_reference() function sets or retrieves the reference field (see dirfile(5)) associated with the dirfile specified by dirfile. If the field_code argument is non-NULL, the reference field for the dirfile will be set to the field specified. If field_code is NULL, the reference field is not modified. The field code should refer to a RAW field, and may not contain a representation suffix.

get_reference() is equivalent to calling dirfile_reference() with field_code set to NULL.

RETURN VALUE

On success, dirfile_reference() and get_reference() return the field code of the dirfile's reference field, which will be field_code, if field_code is non-NULL. If no RAW fields are defined in the dirfile, these functions will return NULL, without raising an error. On error, NULL is returned and the dirfile error is set to a non-zero error value. Possible error values are:

GD_E_ACCMODE: The specified dirfile was opened read-only.
GD_E_ALLOC: The library was unable to allocate memory.
GD_E_BAD_CODE: The field specified by field_code was not found.
GD_E_BAD_DIRFILE: The supplied dirfile was invalid.
GD_E_BAD_FIELD_TYPE: The field specified by field_code was not a RAW field.
GD_E_PROTECTED: The metadata of the primary format file fragment (the file named format in the root dirfile directory) was protected from change. 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).