gd_sarrays man page

gd_sarrays, gd_msarrays — retrieve a list of SARRAY values from a Dirfile

Synopsis

#include <getdata.h>

const char ***gd_sarrays(DIRFILE *dirfile);

const char ***gd_msarrays(DIRFILE *dirfile, const char *parent);

Description

The gd_sarrays() function queries a dirfile(5) database specified by dirfile and generates a read-only list of values of the all top-level SARRAY fields defined in the database, after type conversion to the data type specified by return_type. For a list of valid symbols to use for return_type, see the gd_get_sarray(3) manual page.  

The gd_msarrays() function behaves similarly, but creates a list of values of SARRAY subfields under the parent field parent.

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

The array returned will be de-allocated by a call to gd_close(3) and should not be de-allocated by the caller.  The list returned should not be assumed to be in any particular order, except that it is guaranteed to be in the same order as the list of SARRAY fields returned by gd_field_list_by_type(3) or gd_mfield_list_by_type(3). The number of values in the array can be obtained from a call to gd_nfields_by_type(3) or gd_nmfields_by_type(3).

The caller may not modify any values in the array, nor the array itself.  Doing so may cause database corruption.  The pointer returned is guaranteed to be valid only until the function is called again with the same arguments, or until the dirfile's metadata is modified (by adding, modifying or deleting an entry), or until the array is de-allocated by a call to gd_close(3) or gd_discard(3).

A corresponding list of names for these fields may be obtained by calling gd_field_list_by_type(3) or gd_mfield_list_by_type(3).

Return Value

Upon successful completion, gd_sarrays() and gd_msarrays(3) return a pointer to an array of arrays of strings.  For convenience, both levels of the array are terminated by NULL pointers.

If no SARRAYs are defined in the database, a pointer to a single-element array containing only the terminating NULL is returned.

On error, gd_sarrays() returns NULL and stores a negative-valued error code in the DIRFILE object which may be retrieved by a subsequent call to gd_error(3). Possible error codes are:

GD_E_ALLOC

The library was unable to allocate memory.

GD_E_BAD_DIRFILE

The supplied dirfile was invalid.

GD_E_INTERNAL_ERROR

An internal error occurred in the library while trying to perform the task. This indicates a bug in the library.  Please report the incident to the GetData developers.

A descriptive error string for the error may be obtained by calling gd_error_string(3).

History

The gd_sarrays() function appeared in GetData-0.10.0.

See Also

gd_entry_list(3), gd_error(3), gd_error_string(3), gd_get_sarray(3), gd_nentries(3), gd_open(3), dirfile(5)

Referenced By

gd_get_sarray_slice(3), gd_put_sarray_slice(3).

25 December 2016 Version 0.10.0 GETDATA