debian man page for gd_field_list

gd_field_list(3)						      GETDATA							  gd_field_list(3)

NAME
       gd_field_list -- retrieve a list of fields in a dirfile

SYNOPSIS
       #include <getdata.h>

       const char **gd_field_list(DIRFILE *dirfile);

DESCRIPTION
       The gd_field_list() function queries a dirfile(5) database specified by dirfile and returns a read-only list of names of the all fields de-
       fined in the database.  Notably, this list does not include /META subfields.

       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 ob-
       tained from a call to gd_nfields(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_field_list() is called again on the same DIRFILE object, or until the array is de-allocated by a call to
       gd_close(3).

RETURN VALUE
       Upon successful completion, gd_field_list() returns a pointer to an array of strings containing the names of all the fields defined in  the
       dirfile database.  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.

       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_cbopen(3), gd_error(3), gd_error_string(3), gd_field_list_by_type(3), gd_mfield_list(3), gd_nfields(3), gd_vector_list(3)

Version 0.7.0							  15 October 2010						  gd_field_list(3)