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 variable-sized 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 %%CorpNameShort. 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 the getproplist(3) or fgetproplist(3) routine. To parse the attribute buffer returned by getproplist(3) or fgetproplist(3), you 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 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), sizeof_proplist_entry(3).
Files: libproplist.a, libproplist.so, sys/proplist.h, acl(4).
Daemons: proplistd(8). delim off