proplist - The storing, parsing, and retrieving of
Extended File Attributes
Tru64 UNIX supports the storing, parsing, and retrieving
of Extended File Attributes. An Extended File Attribute
is a name and value pair that is contained in a variablesized
structure called a Property List. A Property List
is part of a file's metadata and can contain abstract name
and value pairs (Extended File Attributes) that can be set
either by the operating system (for example, ACLs and
privileges) or by a user-level application (for example,
PC File Attributes).
Since Extended File Attributes are treated as an extension
to a file's metadata, they are synchronously updated,
thereby ensuring consistency. Note that Extended File
Attributes set by user-level applications are treated as
opaque and can be virtually anything.
To ensure that all Property List names are unique, you
must register your Property List names with Compaq. Those
Property List names with a prefix are reserved by Compaq.
In the case of conflicts, Compaq reserves the right to
arbitrate the naming conventions of Property Lists.
To register a Property List name, send a request by network
mail to or write to:
Tru64 UNIX File System Group
ATTN: Property List Administrator
Compaq Computer Corporation
110 Spit Brook Road
Nashua, NH. 03062-2698
Several user-level routines, listed in the Related Information
section, work together to manipulate Extended File
Attributes. For example: To set attributes, you use the
sizeof_proplist_entry(3) and add_proplist_entry(3) routines
to initialize the Extended File Attribute buffer
passed to setproplist(3) or fsetproplist(3). To fetch
attributes, you use getproplist(3) or fgetproplist(3). To
parse the attribute buffer returned by setproplist(3) or
fsetproplist(3), use the get_proplist_entry(3) routine.
The format of the Extended File Attributes buffer, the
values of the system-wide properties, and the format of
the Property List structures are all defined in sys/proplist.h.
Extended File Attributes are supported by the Advanced
File System (AdvFS), the UNIX File System (UFS), and the
Network File System (NFS). The latter through the use of
the proplistd daemon and the mount -o proplist command.
The archive utilities and support files with Extended File
Attributes. However, third-party archive utilities may
not support Extended File Attributes and, consequently, if
they are used on files with Extended File Attributes, the
Extended File Attributes will be lost.
Functions: add_proplist_entry(3), delproplist(3), fdelproplist(3), fgetproplist(3), fsetproplist(3), get_proplist_entry(3), getproplist(3), setproplist(3),
Files: libproplist.a, libproplist.so, sys/proplist.h,
Daemons: proplistd(8). delim off
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