SIMPLE SOLUTIONS

GD_CONSTANTS(3) - man page online | library functions

Retrieve a list of constant values from a dirfile.

Chapter
18 August 2011
gd_constants(3)                              GETDATA                              gd_constants(3)

NAME

gd_constants — retrieve a list of constant values from a dirfile

SYNOPSIS

#include <getdata.h> const void *gd_constants(DIRFILE *dirfile, gd_type_t return_type);

DESCRIPTION

The gd_constants() function queries a dirfile(5) database specified by dirfile and returns a read-only list of values of the all CONST type fields defined in the database after type conversion to the data type specified by return_type. Notably, this list does not include /META subfields. For a list of valid symbols to use for return_type, see the gd_get_con‐ stant(3) man page. 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-al‐ located by the caller. The list returned should not be assumed to be in any particular order, although it is guaranteed to be in the same order as the list of CONST fields re‐ turned by gd_field_list_by_type(3). The array is unterminated. The number of values in the array can be obtained from a call to gd_nfields_by_type(3). The caller may not modify any values in the array, or the array itself. Doing so may cause database corruption. The pointer returned is guaranteed to be valid only until gd_constants() 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). A corresponding list of names for these fields may be obtained by calling gd_field_list_by_type(3).

RETURN VALUE

Upon successful completion, gd_constants() returns a pointer to an array of values con‐ taining the values of all the constants defined in the dirfile database. If no constants are defined in the database, NULL is returned. On error it returns NULL and sets the dirfile error to a non-zero error value. Possible error values are: GD_E_ALLOC The library was unable to allocate memory. GD_E_BAD_DIRFILE The supplied dirfile was invalid. GD_E_BAD_TYPE The return_type specified 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 devel‐ opers. The dirfile error may be retrieved by calling gd_error(3). A descriptive error string for the last error encountered can be obtained from a call to gd_error_string(3).

SEE ALSO

dirfile(5), gd_open(3), gd_error(3), gd_error_string(3), gd_field_list_by_type(3), gd_get_constant(3), gd_nfields_by_type(3)
Version 0.8.0 18 August 2011 gd_constants(3)
This manual Reference Other manuals
gd_constants(3) referred by gd_hidden(3) | gd_hide(3) | GetData(3pm)
refer to dirfile(5) | gd_cbopen(3) | gd_close(3) | gd_entry_list(3) | gd_error(3) | gd_error_string(3) | gd_get_carray_slice(3) | gd_nentries(3)