L
label
See disk label
LAN (Local Area Network)
Local Area Network. A device communications system that operates over a
limited physical distance, offering high-speed communications channels
optimized for connecting information-processing equipment.
LAT (Local Area Transport)
A DIGITAL protocol that supports communications between host computer
systems and terminal servers with terminals, PCs, printers, modems, and other
devices over LANs.
See also LAN (Local Area Network)
layered product
An optional software product designed to be installed as an added feature of the
DIGITAL UNIX system.
lex
The command that invokes the Lexical Analyzer Generator, a program for
generating other programs that can organize input into units of meaning
(symbols) called lexemes.
See also lexical analyzer, parser, yacc (Yet Another Compiler-Compiler)
lexical analyzer
A program or program fragment for analyzing input and assigning elements of it
to categories to assist in parsing the input. The lex program assists in the creation
of lexical analyzers.
See also parser
Lexical Analyzer Generator
See lex
line editor
An interactive or noninteractive text editor that works on one line of text at a
time.
See also full-screen editor
link
A directory entry referring to a file.
See also hard link, symbolic link
linking loader
A single program that loads, relocates, and links compiled and assembled
programs, routines, and subroutines to create an executable file. Also known as
link loader and linker loader.
lint
A program that checks C code for bugs, portability problems, and errors, such as
mismatched argument types and uninitialized variables.
literal
1. A value expression representing a constant.
2. A specific symbol that cannot be modified during the translation of a program.
local area network
See LAN (Local Area Network)
local area transport
See LAT (Local Area Transport)
local host
The computer system to which a user's terminal is directly connected.
lock file
A file that indicates that operations on one or more other files are restricted or
prohibited. The presence of the lock file can be used as the indication, or the lock
file can contain information describing the nature of the restrictions. For
example, the DIGITAL UNIX setld utility creates a lock file for each product kit
subset that it installs. If a given product includes subsets that require the
presence of a previously installed subset, setld places in the earlier subset's lock
file the names of the later subsets to prevent inadvertent deletion of the earlier
subset.
locking
1. In software installation by the setld utility, the act of inserting a new subset's
name in the lock file of an existing subset so that an attempt to remove the latter
subset will flag the user with a dependency warning.
2. In a version control system, the creation and use of information flagging a
version control file as being checked out for editing.
locking mechanism
In a version control system, a way to prevent overlapping and concurrent
changes to a file. SCCS uses p-files to indicate which files are currently out for
editing; RCS creates locks by editing the RCS file to insert lock information.
log in
To begin using a computer system, usually by entering one's login name and a
secret password; to gain access to and communicate with the operating system
as an authorized user.
login directory
See home directory
login group
The primary classification that establishes the access permission for the files
created by the user.
See also group
login name
The name that identifies a user to a computer system and to other users of the
system. When logging into the system, the user enters this name and (usually) a
secret password. Also known as user name.
login shell
The shell that a user uses by default upon logging into the system. It is specified
by the user's entry in the passwd file.
log out, log off
To stop using a computer system, usually by entering a command that tells the
operating system that the user is ending the current session.
loop
1. A sequence of instructions that is executed repeatedly until a specified
condition is satisfied.
2. In the UNIX virtual memory system, the page clusters in main memory that are
repeatedly scanned for replacement.
See also infinite loop
