OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components

5.6.5 Making or Retrieving Headers

The dce_db_std_header_init( ) routine initializes a standard backing store header from

the values the caller provides in its arguments. It places the values into the header only

and does not write into the backing store ﬁle. The dce_db_header_fetch() routine

retrieves the header of an object in the backing store.

5.6.6 Performing Iteration

The following routines iteratively traverse all of the keys (name or UUID) in a backing

store. The order of retrieval of the keys is indeterminate; they are not sorted, nor are

they necessarily returned in the order in which they were originally stored. It is strongly

recommended to use the locking and unlocking routines, dce_db_lock() and

dce_db_unlock( ), whenever performing iteration.

dce_db_iter_start()

This routine prepares for the start of iteration.

dce_db_iter_next( )

This routine returns the key for the next item from a backing store that is

indexed by name or by UUID. The db_s_no_more status code indicates

that there are no more items.

dce_db_iter_next_by_name( )

This routine returns the key for the next item only from a backing store

that is indexed by name. Again, db_s_no_more indicates that no items

remain.

dce_db_iter_next_by_uuid()

This routine returns the key for the next item only from a backing store

that is indexed by UUID. Again, db_s_no_more indicates that no items

remain.

dce_db_iter_done( )

This routine is counterpart to dce_db_iter_start( ) and should be called

when iteration is done.

dce_db_inq_count( )

This routine returns the number of items in a backing store.

5.6.7 Deleting Items from a Backing Store

The following routines delete an item from a backing store.

dce_db_delete( )

This routine deletes an item from a backing store that is indexed by

name or by UUID. The key’s type must match the ﬂag that was used in

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