OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components
The attribute value is a string of encrypted bytes. This encrypted data can be passed
over the network and is available to user-developed applications.
• i18n_data
An internationalized string of bytes with a tag identifying the OSF registered codeset
used to encode the data.
• uuid
A DCE UUID.
• attr_set
The value is an attribute set, a vector of attribute type UUIDs used to associate
multiple related attribute instances (members of the set). The vector contains the
UUIDs of each member of the set. Attribute sets provide a flexible way to group
related attributes on an object for easier search and retrieval.
The attribute type UUIDs referenced in an attribute set instance must correspond to
existing attribute schema entries. Although the members specified in a set are
generally expected to be attached to the object to which the set instance is attached,
no checking is done to confirm that they are. Thus, it is possible to create an attribute
set instance on an object before creating member attribute instances on that object. A
query on such an attribute set returns all instances of member attributes that exist on
the object along with a warning that some attribute types were missing.
Note that attribute sets cannot be nested; a member UUID of an attribute set cannot
itself identify an attribute set.
A query on an attribute set expands to a query per the set’s members. In other words,
an attribute lookup operation on an attribute set returns all attribute instances that are
members of the set, not the set instance itself. (Certain operations, such as
sec_rgy_attr_set_lookup_by_id( ) and sec_rgy_attr_lookup_by_name(), can
retrieve attribute set instances.)
Updates to an attribute set (sec_rgy_attr_update()) do not expand the update to its
members but apply only to the attribute set. Since the value carried by a set instance
is a vector containing the UUIDs of the member attribute types, an update makes
changes only to the set’s members, not the values carried by those member attributes.
Deletions of attribute sets delete only the set instance, not the member instances.
Since the attributes that are set members exist independently of the attribute set, they
can be manipulated directly like any other attribute.
• binding
The attribute value is a sec_attr_binding_info_t type containing authentication,
authorization, and binding information suitable for communicating with a DCE
server.
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