OSF DCE Application Development Guide--Core Components

The Extended Attribute API

Note that, if the deletion of any attribute instance in the array fails, all fail. However, to

help pinpoint the cause of the failure, the call identiﬁes the ﬁrst attribute whose deletion

failed in a failure index by array element number.

28.3.3 Reading Attribute Instances

This section describes the calls that read attribute instances, and it describes the cursor

used by the sec_rgy_attr_lookup_by_id( ) call.

28.3.3.1 Using sec_rgy_attr_cursor_t with sec_rgy_attr_lookup_by_id( )

The sec_rgy_attr_lookup_by_id() call, which reads attributes for a speciﬁed object,

uses a cursor of type sec_attr_cursor_t. This cursor must be allocated before it can be

used as input to the sec_rgy_attr_lookup_by_id( ) call. In addition, it can also be

initialized to the ﬁrst attribute in the speciﬁed object’s list of attributes, although this is

not required. After use, the resources allocated to the sec_attr_cursor_t must be

released.

The following calls allocate, initialize, and release a sec_attr_cursor_t for use with the

sec_rgy_attr_lookup_by_id( ) call:

• sec_rgy_attr_cursor_init( )

The sec_rgy_attr_sch_cursor_init( ) call allocates resources to and initializes the

cursor to the ﬁrst attribute in the speciﬁed object’s list of attributes. This call also

supplies the total number of attributes attached to the object as part of its output. The

cursor allocation is a local operation. The cursor initialization is a remote operation

and makes a remote call to the registry.

• sec_rgy_attr_cursor_alloc()

The sec_rgy_attr_cursor_alloc() call allocates resources to the cursor but does not

initialize the cursor. However, since the sec_rgy_attr_lookup_by_id() call will

initialize the cursor if it is passed in uninitialized, you may prefer this call to limit

the number of remote calls performed by the application. Be aware that the

sec_rgy_attr_cursor_init( ) call provides the total number of attributes attached to

the speciﬁed object, a piece of information not provided by this call.

• sec_rgy_attr_cursor_release( )

The sec_rgy_attr_cursor_release() call releases all resources allocated to a

sec_attr_cursor_t cursor used with the sec_rgy_attr_lookup_by_id( ) call.

• sec_rgy_attr_cursor_reset( )

The sec_rgy_attr_cursor_reset() call reinitializes a sec_attr_cursor_t cursor used

with the sec_rgy_attr_lookup_by_id( ) call. The reset cursor can then be used

without releasing and reallocating.

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