NAME

       gd_mfield_list — retrieve a list of fields in a dirfile

SYNOPSIS

       #include <getdata.h>

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

DESCRIPTION

       The  gd_mfield_list()  function  queries  a  dirfile(5)  database specified by dirfile and
       returns a read-only list of names of the all metafields for the specified parent field  in
       the database.

       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.  The array is terminated by a NULL pointer.  The number of strings in the array can
       be obtained from a call to gd_nmfields(3).

       The  caller  may  not  modify any strings in the array, or the array itself.  Doing so may
       cause database  corruption.   The  pointer  returned  is  guaranteed  to  be  valid  until
       gd_mfield_list()  is  called  again  with  the  same  arguments, or until the array is de-
       allocated by a call to gd_close(3).

RETURN VALUE

       Upon successful completion, gd_mfield_list() returns a pointer  to  an  array  of  strings
       containing  the names of all the metafields of the given parent.  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_CODE
               The supplied parent field code was not found, or referred to a metafield itself.

       GD_E_BAD_DIRFILE
               The supplied dirfile was invalid.

       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_mfield_list_by_type(3),
       gd_mvector_list(3), gd_nfields(3)