|.TERM|Ubik
|.ACR|
	|.DEFIN|1|DFS: A library of utilities that the DFS Fileset
Location Server and the DFS Backup Server use to keep individual copies of
their databases synchronized.
		|.XREF|secondary site
		|.XREF|synchronization site
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|ublock
|.ACR|
	|.DEFIN|1|*
		|.XREF|user block
		|.BOOK|
		|.TOPIC|
|.TERM|UDP
|.ACR|
	|.DEFIN|1|*
		|.XREF|User Datagram Protocol
		|.BOOK|OSNetAppProgGd
		|.TOPIC|
|.TERM|UID
|.ACR|
	|.DEFIN|1|*
		|.XREF|user number
		|.BOOK|
		|.TOPIC|
|.TERM|umask
|.ACR|
	|.DEFIN|1|*
		|.XREF|user number
		|.BOOK|
		|.TOPIC|
|.TERM|unary expression
|.ACR|
	|.DEFIN|1|An expression that contains one operand.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|unconfigure
|.ACR|
	|.DEFIN|1|To take a device from an available (configured) state to an
unavialable state.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|undef statement
|.ACR|
	|.DEFIN|1|A preprocessor statement that causes the preprocessor to end the
scope of a preprocessor definition.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|unexport
|.ACR|
	|.DEFIN|1|RPC: To remove binding information from a server
entry in a name service database.
		|.XREF|export
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|unformatted file
|.ACR|
	|.DEFIN|1|A file displayed with the data that is not arranged with
particular characters. Contrast with \(LI\s12\f(HIformatted file\(LI\s12\fH.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|union
|.ACR|
	|.DEFIN|1|A variable that can hold any one of several data types, but only
one data type at a time.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|union tag
|.ACR|
	|.DEFIN|1|The identifier that names a union data type.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|uniquifier
|.ACR|
	|.DEFIN|1|DFS: A piece of data that, in combination with a fileset
ID, produces a globally unique identifier.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|Universal Unique Identifier
|.ACR|UUID
	|.DEFIN|1|RPC: An identifier that is
immutable and unique across time and space. A UUID can uniquely
identify an entity such as an RPC interface or object.
		|.XREF|interface UUID
		|.XREF|object UUID
		|.XREF|type UUID
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|UUID
|.ACR|
	|.DEFIN|1|*
		|.XREF|Universal Unique Identifier
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|UNIX operating system
|.ACR|
	|.DEFIN|1|A highly-portable operating system for computers,
implemented in the C language.  It is especially suitable for multiprocessor,
graphics, and vector-processing systems.
		|.XREF|
		|.BOOK|OSNetAppProgGd
		|.TOPIC| 
|.TERM|Unix-to-Unix Copy Program
|.ACR|UUCP
	|.DEFIN|1|A group of programs and files that function as a background
process. It includes a set of directories, files, programs, and commands that
allow the user to communicate with a remote system over a dedicated line or a
telephone line.
		|.XREF|
		|.BOOK|OSNetComAdminGd
		|.BOOK|OSUsersGd
		|.TOPIC|
	|.DEFIN|2|The command \fBuucp\fP that starts file copying from
one or more sources to a single destination.
		|.XREF|
		|.BOOK|OSNetComAdminGd
		|.BOOK|OSUsersGd
		|.TOPIC|
|.TERM|unmarshalling
|.ACR|
	|.DEFIN|1|RPC: The process by which a stub disassembles
incoming network data and converts it into local data in the
appropriate local data representation.
		|.XREF|marshalling
		|.XREF|network data
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|unnumbered information frame
|.ACR|UI
	|.DEFIN|1|A frame in unnumbered format, used to transfer unnumbered
control functions.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|unpredictable
|.ACR|
	|.DEFIN|1|A violation of an architecture rule that an 
implementation is not required to report. Results can include an error report 
from a threads call, the operating system, or the hardware; a hang or 
deadlock of the program; or an incorrect operation of the program without 
indication of error.
		|.XREF|illegal
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|unprivileged instructions
|.ACR|
	|.DEFIN|1|Ordinary instructions such as load, store, add, and shift
typically used by application programs. Contrast with \(LI\s12\f(HIprivileged
instructions\(LI\s12\fH.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|unprivileged state
|.ACR|
	|.DEFIN|1|A hardware protection state in which the processor can only run
unprivileged instructions. Contrast with \s12\f(HIprivileged state\s12\fH.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|unset positional parameter
|.ACR|
	|.DEFIN|1|A positional parameter that no longer has an argument in that
position.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|upclient
|.ACR|
	|.DEFIN|1|DFS: A process that runs on DFS server machines, taking
copies of common configuration files and new DFS server process binary files
from central sources.
		|.XREF|Update Server
		|.XREF|upserver
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|update
|.ACR|
	|.DEFIN|1|An improvement for some part of the system.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|2|To add, change, or delete items.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|3|To modify a file with current information according to a
specified procedure.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|update propagation
|.ACR|
	|.DEFIN|1|An immediate attempt to apply a change to all replicas 
of the CDS directory in which the change was just made. An update propagation 
delivers changes in a more efficient and timely way than a skulk, which is the 
periodic distribution of a whole collection of changes.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|Update Server
|.ACR|
	|.DEFIN|1|DFS: A process that guarantees that all
DFS server machines in a cell have the same versions of common configuration
files and the same versions of DFS binary files appropriate for their machine
type. It has a server portion called the
.B "upserver"
and a client portion called the
.B "upclient" .
		|.XREF|upclient
		|.XREF|upserver
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|Update Timestamp
|.ACR|UTS
	|.DEFIN|1|An attribute that identifies the time at which 
the most recent change was made to any attribute of a particular CDS name. 
For directories, the UTS reflects changes made only to attributes 
that apply to the directory as a whole (not one of its replicas).
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|upload
|.ACR|
	|.DEFIN|1|To transfer data from one computer to another. Typically, users
upload from a small computer to a larger one.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|upserver
|.ACR|
	|.DEFIN|1|DFS: A process that runs on DFS server machines, making
local copies of common configuration files and new DFS server process
binary files available to other DFS server machines.
		|.XREF|upclient
		|.XREF|Update Server
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|user
|.ACR|
	|.DEFIN|1|GDS: The end user of the directory; the entity or person that
accesses the directory. A user can be an application program that is calling 
the directory interface on behalf of a human user.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
	|.DEFIN|2|The name associated with an account.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|3|Anyone requiring the services of a computing system.\s12\fH
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user account
|.ACR|
	|.DEFIN|1|*
		|.XREF|account
		|.BOOK|
		|.TOPIC|
|.TERM|user address list
|.ACR|
	|.DEFIN|1|In X.25 communications, the address list that a user can use
with the \s12\f(HBxtalk\s12\fH command to make outgoing calls.
		|.XREF|address list
		|.XREF|system address list
		|.BOOK|
		|.TOPIC|
|.TERM|user area
|.ACR|
	|.DEFIN|1|The parts of main storage and disk available to the user.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user authentication cache module
|.ACR|
	|.DEFIN|1|DFS: The part of the DFS Cache Manager that maintains
per-user Kerberos tickets and credential information.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|user block
|.ACR|
	|.DEFIN|1|A data structure maintained by the kernel that contains system
information about a user process, such as its real and effective user IDs,
the list of open file descriptors, and signal-handling settings. The
\s12\f(HBuser\s12\fH structure (defined in the
\s12\f(HB/usr/include/sys/user\s12\fH header file) specifies the exact
information that is kept in the user block.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user data
|.ACR|
	|.DEFIN|1|DFS: The data in a fileset or aggregate, such as
applications and data files, created and referenced by users of the system.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|user data segment
|.ACR|
	|.DEFIN|1|In kernel mode, the virtual memory segment that contains user
data, which consists of initialized data variables.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|User Datagram Protocol
|.ACR|UDP
	|.DEFIN|1|A protocol of the Internet
Protocol (IP) family.
		|.XREF|
		|.BOOK|introDCE
		|.TOPIC|
	|.DEFIN|2|Allows a datagram made of packet switched communications in the
environment of an interconnected set of computer networks. It assumes that
Internet Protocol is the underlying protocol.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|3|The Internet protocol that allows application programs on
remote machines to send datagrams to one another.  UDP uses IP to deliver
the datagrams.
		|.XREF|
		|.BOOK|OSNetAppProgGd
		|.TOPIC|
|.TERM|user-defined variable
|.ACR|
	|.DEFIN|1|A shell variable to which the user assigns a character string as
a value.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user ID
|.ACR|
	|.DEFIN|1|*
		|.XREF|user identification
		|.BOOK|OSUsersGd
		|.BOOK|OSAdminGd
		|.TOPIC|
|.TERM|user identification
|.ACR|user ID
	|.DEFIN|1|A unique string that identifies an operator to the
system. This string of characters limits the functions and information the
operator can use. Often, the user ID can be substituted in commands that take
a user's login name as an argument.
		|.XREF|
		|.BOOK|OSUsersGd
		|.BOOK|OSAdminGd
		|.TOPIC|
	|.DEFIN|2|A parameter that specifies the user ID under which the
application or transaction program runs.
		|.XREF|
		|.BOOK|OSUsersGd
		|.BOOK|OSAdminGd
		|.TOPIC|
|.TERM|user interface
|.ACR|
	|.DEFIN|1|The means by which a user communicates with a system, program,
or device.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|2|The hardware, software, or both that implements a user
interface, allowing the user to interact with and perform operations on a
system, program, or device. Examples are a keyboard, mouse, command language,
or windowing subsystem.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user level
|.ACR|
	|.DEFIN|1|The part of a system where utilities, the 
user interface, and other user programs are performed.
		|.XREF|kernel level
		|.BOOK|
		|.BOOK|
		|.TOPIC|
|.TERM|user level initialization
|.ACR|
	|.DEFIN|1|This level of initialization continues from kernel
initialization.  It encompasses the user level utilities that need to
be performed before a user receives a system prompt.  These user level
utilities use the system call interface.
		|.XREF|kernel level initialization
		|.BOOK|DesignofOS
		|.TOPIC|
|.TERM|user limit
|.ACR|ulimit
	|.DEFIN|1|A limitation placed on a user process for resources such as disk
space and virtual memory space. User limits can be set by the
\s12\f(HBulimit\s12\fH system call.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user mode
|.ACR|
	|.DEFIN|1|A mode in which a process is carried out in the user's program
rather than in the kernel. Contrast with \s12\f(HIkernel mode\s12\fH.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user number
|.ACR|UID
	|.DEFIN|1|A number that uniquely identifies a user to the system.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user process
|.ACR|UID
	|.DEFIN|1|The instance of a program that is being executed by
the operating system. The process has a user context, which is address space
that is accessible to it while running in user mode and a kernel context,
which is maintained and available to the kernel only. 
		|.XREF|
		|.BOOK|OSUsersGd
		|.TOPIC|
|.TERM|user profile
|.ACR|
	|.DEFIN|1|A file in the user's home directory named
\s12\f(HB.profile\s12\fH that contains shell commands that set initial
user-defined characteristics and defaults for the login session.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|user space
|.ACR|
	|.DEFIN|1|The address space seen by a process in user mode.
		|.XREF|user structure
		|.BOOK|
		|.TOPIC|
|.TERM|user structure
|.ACR|
	|.DEFIN|1|In kernel mode, the data area that contains information that
must be accessible while a process executes. One user structure is allocated
for each active process.
		|.XREF|per process data area
		|.XREF|user block
		|.BOOK|
		|.TOPIC|
|.TERM|username
|.ACR|
	|.DEFIN|1|A string of characters that uniquely identifies a user to the
system.
		|.XREF|
		|.BOOK|OSUsersGd
		|.TOPIC|
|.TERM|UTC
|.ACR|
	|.DEFIN|1|*
		|.XREF|Coordinated Universal Time
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|utility
|.ACR|
	|.DEFIN|1|A service. In programming, a program that performs a common
service function.
		|.XREF|
		|.BOOK|
		|.TOPIC|
	|.DEFIN|2|The capability of a system, program, or device to perform the
functions for which it is designed.
		|.XREF|
		|.BOOK|
		|.TOPIC|
|.TERM|UTS
|.ACR|
	|.DEFIN|1|*
		|.XREF|Update Timestamp
		|.BOOK|introDCE
		|.TOPIC|
|.TERM|UUCP
|.ACR|
	|.DEFIN|1|*
		|.XREF|Unix-to-Unix Copy Program
		|.BOOK|OSUsersGd
		|.TOPIC|
	|.DEFIN|2|Unix-to-Unix Copy Program, a program that allows
communications between systems that are connected by telephone or hardware
wires.
		|.XREF|
		|.BOOK|OSNetComAdminGd
		|.TOPIC|
|.TERM|UFS
|.ACR|
        |.DEFIN|1|*
               |.XREF|UNIX File System
               |.BOOK|introDCE
               |.TOPIC|
|.TERM|UNIX File System
|.ACR|UFS
        |.DEFIN|1|A section of the UNIX file tree that is physically
contained on a single device or disk partition and that can be separately
mounted, dismounted, and administered.
               |.XREF|
               |.BOOK|introDCE
               |.TOPIC|
