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H5G_ITERATE

Iterates an operation over the entries of a group.

This function is deprecated in favor of the function H5L_ITERATE.

Procedure:

H5G_ITERATE(loc_id, name, idx, operator, operator_data)

Signature:

int H5Giterate(hid_t loc_id, const char *name, int *idx, H5G_iterate_t operator, void *operator_data )

There is no direct FORTRAN couterpart for the C function H5Giterate. Instead, that functionality is provided by two FORTRAN functions:

SUBROUTINE h5gn_members_f(loc_id, name, nmembers, hdferr)           
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: loc_id        ! File or group identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name        ! Name of the group 
  INTEGER, INTENT(OUT) :: nmembers            ! Number of members in the group
  INTEGER, INTENT(OUT) :: hdferr              ! Error code 
                                              ! 0 on success and -1 on failure
END SUBROUTINE h5gn_members_f
SUBROUTINE h5gget_obj_info_idx_f(loc_id, name, idx, & 
                                 obj_name, obj_type, hdferr)           
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: loc_id        ! File or group identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name        ! Name of the group 
  INTEGER, INTENT(IN) :: idx                  ! Index of member object 
  CHARACTER(LEN=*), INTENT(OUT) :: obj_name   ! Name of the object 
  INTEGER, INTENT(OUT) :: obj_type            ! Object type : 
                                              !     H5G_LINK_F 
                                              !     H5G_GROUP_F 
                                              !     H5G_DATASET_F 
                                              !     H5G_TYPE_F 
  INTEGER, INTENT(OUT) :: hdferr              ! Error code 
                                              ! 0 on success and -1 on failure
END SUBROUTINE h5gget_obj_info_idx_f

Parameters:
hid_t loc_idIN: File or group identifier.
const char *nameIN: Group over which the iteration is performed.
int *idxIN/OUT: Location at which to begin the iteration.
H5G_iterate_t operator    IN: Operation to be performed on an object at each step of the iteration.
void *operator_dataIN/OUT: Data associated with the operation.

Description:

H5Giterate iterates over the members of name in the file or group specified with loc_id. For each object in the group, the operator_data and some additional information, specified below, are passed to the operator function. The iteration begins with the idx object in the group and the next element to be processed by the operator is returned in idx. If idx is NULL, then the iterator starts at the first group member; since no stopping point is returned in this case, the iterator cannot be restarted if one of the calls to its operator returns non-zero. H5Giterate does not recursively follow links into subgroups of the specified group.

The prototype for H5G_iterate_t is:

    typedef herr_t (*H5G_iterate_t) (hid_t group_idconst char * member_namevoid *operator_data);

 

The operation receives the group identifier for the group being iterated over, group_id, the name of the current object within the group, member_name, and the pointer to the operator data passed in to H5Giterateoperator_data.

The return values from an operator are:

  • Zero causes the iterator to continue, returning zero when all group members have been processed.
  • Positive causes the iterator to immediately return that positive value, indicating short-circuit success. The iterator can be restarted at the next group member.
  • Negative causes the iterator to immediately return that value, indicating failure. The iterator can be restarted at the next group member.

H5Giterate assumes that the membership of the group identified by name remains unchanged through the iteration. If the membership changes during the iteration, the function's behavior is undefined.

H5Giterate is not recursive. In particular, if a member of name is found to be a group, call it subgroup_aH5Giterate does not examine the members of subgroup_a. When recursive iteration is required, the application must handle the recursion, explicitly calling H5Giterate on discovered subgroups.

Returns:

Returns the return value of the last operator if it was non-zero, or zero if all group members were processed. Otherwise returns a negative value.

Example:

Coming soon!

 

History:
Release    C
1.8.0Function deprecated in this release.

--- Last Modified: January 03, 2018 | 03:08 PM