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DFANlablist/dallist

int DFANlablist(char *filename, uint16 tag, unit16 ref_list[], char *label_list, int list_len, intn label_len, intn start_pos)

filename IN:

Name of the file

tag IN:

Tag to be queried

ref_list OUT:

Buffer for the returned reference numbers

label_list OUT:

Buffer for the returned labels

list_len IN:

Size of the reference number list and the label list

label_len IN:

Maximum length allowed for a label

start_pos IN:

Starting position of the search

Purpose

Returns a list of all reference numbers and labels (if labels exist) for a given tag.

Return value

Returns the number of reference numbers found if successful and FAIL (or -1) otherwise.

Description

Entries are returned from the start_pos entry up to the list_len entry.

The list_len determines the number of available entries in the reference number and label lists, label_len is the maximum length allowed for a label, and start_pos tells which label to start reading for the given tag. (If start_pos is 1, for instance, all labels will be read; if start_pos is 4, all but the first 3 labels will be read.) The ref_list contains a list of reference numbers for all objects with a given tag. The label_list contains a corresponding list of labels, if any. If there is no label stored for a given object, the corresponding entry in label_list is an empty string.

Taken together, the ref_list and label_list constitute a directory of all objects and their labels (where they exist) for a given tag. The label_list parameter can display all of the labels for a given tag. Or it can be searched to find the reference number of a data object with a certain label. Once the reference number for a given label is found, the corresponding data object can be accessed by invoking other HDF routines. Therefore, this routine provides a mechanism for the direct access to data objects in HDF files.

FORTRAN

integer function dallist(filename, tag, ref_list, label_list, list_len, label_len, start_pos)

character*(*) filename, label_list

integer ref_list(*)

integer list_len, label_len, start_pos



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HDF Reference Manual - 07/29/98, NCSA HDF Development Group.