OSF DCE Application Development Guide--Core Components

The Extended Attribute API

28.1.3 Attribute Type Components

The sec_attr_schema_entry_t data type deﬁnes an attribute type. This data type

contains attribute type identiﬁers and characteristics.

The identiﬁers of attribute types are a name and a UUID. Generally, the name is used for

interactive access and the UUID for programmatic access.

Attribute type characteristics describe the format and function of the attribute type and

thus control the format and function of instances of that type. These characteristics, all

speciﬁed in the sec_attr_schema_entry_t data type, are described in the following

sections.

28.1.3.1 Attribute Encoding

Attribute encoding deﬁnes the legal encoding for instances of the attribute type. The

encoding controls the format of the attribute instance values, such as whether the

attribute value is an integer, string, a UUID, or a vector of UUIDs that deﬁne an attribute

set.

Attribute encodings are speciﬁed in the sec_attr_encoding_t data type (fully described

in the OSF DCE Application Development Reference).

The possible encodings for attribute types are

• any

The attribute instance value can be of any legal encoding type.

• void

The attribute instance has no value. It is simply a marker that is either present or

absent.

• printstring

The attribute value is a printable IDL character string from the DCE Portable

Character Set (PCS).

• printstring_array

The attribute value is an array of print strings.

• integer

The attribute value is a signed 32-bit integer.

• bytes

The attribute value is a string of bytes. The byte string is assumed to be a pickle or is

otherwise a self-describing type.

• conﬁdential_bytes

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