An identifier followed by a semicolon
and is the target of a goto statement.
labeled statement
A C language statement
that contains one or more identifiers each followed by a colon and a
statement.
LAN
Local area network.
language work area (LWA)
An I-stream unique
work area used by C language secondary library routines.
LC
Loosely coupled.
LCB
Link control block.
leap seconds
The adjusted difference between
Greenwich mean time (GMT) and the time established as Absolute Time by the
National Bureau of Standards.
LEID
In communications, the logical endpoint
identifier. In coupling facility (CF) support, the list entry
identifier.
LFW
Library function work area.
LGF
Loader general file.
library
A collection of functions, function
calls, subroutines, or other data.
library function
A function available to all
C application programs that provides the programmer with a generic service,
such as determining the length of a string of characters. Library
functions are provided so that C application programs can link to generally
available service routines to perform their tasks.
library function work area (LFW)
Part of the
first stack frame attached to an ECB that is used by C library
functions.
library interface scripts
Files that list
functions contained in a library and provide an index number for that
function. These files are used by the library interface tool (LIBI) to
create library stubs.
library members
Files of object code that
are components of library load modules (LLMs) or dynamic link libraries
(DLLs). For example, CASSART is a library member file of CISO.
library work space
A performance-critical
macro area that is used by library functions that need storage to build macro
expansions and do not give control to any other real-time segments while
macros are running.
LIBVEC
A vector of library function
addresses defined by the library interface script and linked into the library
load module. It is used in the call linkage to library
functions.
limited lock facility (LLF)
A hardware RPQ
required for DASD control units shared among multiple CPCs in a loosely
coupled multiprocessing environment. It is used to synchronize the
modification of the shared database. See also external locking
facility (XLF).
limited resource session
An SNA session that
traverses a switched link and can be deactivated by the LU when it is no
longer being used by a conversation.
line multiplexing
The ability to support
multiple terminals on a communication line.
line status table (LSTB)
The system table
that contains entries for every non-SNA communication line in the
network. The system uses this table to control I/O from non-SNA sources
in the network.
link
In the TPF file system, a connection
between one or more file names and an associated i-node. Synonym for
directory entry. To interconnect items of data or portions
of one or more computer programs; for example, the linking of object
programs by a linkage editor or linking data items by pointers. (T)
linkage editor
A program that resolves
cross-references between separately compiled object modules and then assigns
final addresses to create a single load module.
link control block (LCB)
A record used to
indicate correct or incorrect reception of an SLC data message block and to
provide information regarding the status of an SLC link.
link-edited modules
The files of load module
code produced by the linkage editor.
list entry
An entry on a list in a coupling
facility (CF) list structure. A list entry consists of list entry
controls and can also include a data entry, an adjunct area, or both.
See also adjunct area and data entry.
list entry controls
Items that contain
control information that is associated with a list in a coupling facility (CF)
list structure. See list entry.
list entry identifier (LEID)
An identifier
assigned by the coupling facility (CF) to each list entry that is in use in
the CF list structure.
list header
A header that anchors the list
to the coupling facility (CF) list structure and contains control information
(known as list controls) that is associated with the list. See also
list controls.
list notification vector
An array of bits
that contain an indication of whether a monitor list in a coupling facility
(CF) is in an empty state or a nonempty state.
list processing
The cyclic dispatching
routine performed by the CPU loop that allocates system resources to entries
on a first-in-first-out basis.
lists
Queues of work to be processed by the
CPU loop.
list structure
See coupling facility
list structure.
listener
A TCP/IP application that monitors
information about incoming network connections.
little endian
A method of representing data
such that the lower numbered bytes of the data are less significant.
Intel-based personal computers (PCs) and IBM RISC System/6000 machines use
this format.
live testing
The online testing procedure
that uses terminal input rather than simulated batch input.
LLF
Limited lock facility.
LM
Logon manager.
LMA
Long message assembly.
LMT
Long message transmitter.
LNIATA
The line number, interchange address,
and terminal address used to address a remote device in an ALC network.
load
The process by which programs are read
from an input device by one of the loaders. See auxiliary
loader, E-type loader, general file loader,
and data loader.
load balancing
The system routine that
decides which I-stream engine is to process an entry based on the activity in
all I-stream engines in the CPC.
load deck
The control cards or card image
input used to create all load media (including loader general
files).
loader general file (LGF)
The
disk module that contains programs and keypoints required to initialize a
system. It is a sequential collection of records created offline under
MVS control.
load function
The E-type loader
function that reads sets of programs from an input device.
load module
All or part of a computer
program in a form suitable for loading into main storage for execution.
A load module is usually the output of a linkage editor.
loadset
A group of programs identified by a
unique name on which E-type loader functions can be performed.
loadset directory (LSD)
The structure used
by the E-type loader that contains information about every loadset in
the system.
local area network (LAN)
A computer network
located within a limited geographical area.
local cache buffers
Buffers allocated by
logical record cache support that contain copies of data that is shared among
cache users. Users read data from permanent storage to their local
cache buffers and write data from their local cache buffers to permanent
storage.
local cache vector
An array of bits that
contain an indication of whether data in the local cache buffer is
valid. There is one local cache vector for each cache user.
local symbol table
In expression
enhancements for the TPF debuggers, a table that contains all symbols included
in the assembler program and the data macros (DSECTS) the program invokes
except for those symbols that are defined in the common symbol table.
The TPFSYM offline program extracts DSECT or symbol definitions from the
SYSDATA file that is generated by the assembler and saves the definitions in
the ADATA file. The offline loader then loads the ADATA file to the TPF
system.
locale
Characteristics of the geographic
area, such as time zone, character editing, monetary symbols and formatting,
and nonmonetary formatting. The locale definition is built using the
EDCLOC assembler macro. The setlocale function is used to
select alternate locales.
localedef utility
A utility that processes
locale definition files and produces the locale load modules.
locate
A modified REQTAIL logon manager
private protocol RU used by the TPF system to solicit a SESINIT session
initiation RU. See locate reply.
locate reply
A modified SESINIT logon
manager private protocol RU used by the VTAM logon manager to respond to a TPF
Locate request. It contains a BIND image for the TPF system to send on
the link specified as the last tail in the tail vector.
lock
A serialization mechanism by which a
specific resource is restricted for the use of the holder of the lock.
lock holder
A processor or processors that
currently hold a lock.
lock table
An array of exclusive locks that
you can use to serialize access to coupling facility (CF) list structure
resources such as lists or list entries. See coupling facility
(CF) list structure.
lock waiter
A processor or processors
waiting to obtain a lock.
log A file that contains messages issued
from an application or system program.
To record; for example to log all messages to tape.
See also syslog daemon.
log collection
A type of collection with
ordered, nonunique elements that are not accessible by a key. Elements
are ordered by arrival sequence. The collection cannot be expanded and
the elements will wrap when the collection becomes full; that is, the
newest element will replace the oldest element in the collection.
log manager
A manager that controls the
recovery log and recovery actions.
log processor
In TPF transaction services,
the program that allows a user to log on to an application.
LOGI state
The state a terminal is in when
it is not connected (logged in) to an application.
logical address
The address found in the
instruction address portion of the program status word (PSW). If
address translation is off, the logical address is the real address. If
address translation is on, the logical address is the virtual address.
See also absolute address, physical address, real
address, and virtual address.
logical record cache
A cache that provides
high-speed access to data, which enables you to develop data sharing programs
with improved performance. You can use a logical record cache for data
consistency, which ensures the validity of the data that is shared, and to
keep track of data that resides in permanent and local storage, but is not
stored in the cache itself.
logical DASD subsystem
A subsystem
consisting of 2 storage directors, attached to the same DASD strings, together
with those DASD strings.
logical endpoint identifier (LEID)
An
identifier that is used to give a resource a pseudo line, interchange address,
and terminal address.
logical link
A path for data to be
transmitted between an adapter on a CLAW workstation and the TPF
system.
logical processor
The symbolic
identification assigned to a processor in a loosely coupled complex.
logical storage block
Temporary main storage
requested by an E-type program, dispensed in fixed sizes of 128, 381,
1055, and 4095 bytes. See also TPF block.
logical unit of work
See unit of
work.
logon manager (LM)
A VTAM application that
provides logon services for the TPF system. The TPF system communicates
with the logon manager regarding the status of its applications on CLU
sessions.
long constant
An integer constant followed
by the letter l (el) or L.
long message assembly (LMA)
The process by
which segmented SNA and non-SNA input messages are assembled into one
unit.
long message transmitter (LMT)
A program
package that is used to queue and transmit long, non-SNA messages to ALC
printer devices. LMT is also known as the SENDL postprocessor.
long-term pool records
Pool records that are
maintained for an indefinite period of time, at least longer than the life of
a transaction.
longevity
The length of time (seconds,
hours, days, weeks, months) during which file pool records are
maintained.
lookaside storage buffer
A temporary storage
area where a copy of the data is saved to avoid refetching the data on every
access. The data is retrieved from the temporary storage area instead
of its permanent residence.
loosely coupled complex
Two or more CPCs
sharing a common set of DASD and using an external lock facility (XLF) to
synchronize multiple CPC access to the DASD records.
loosely coupled (LC) facility
A function in
the High Performance Option (HPO) feature that allows multiple CPCs to share a
common database.
low address protection
A hardware facility
that provides protection against the destruction of main storage information
used by the CPU during interrupt processing; accomplished by prohibiting
instructions from storing with effective addresses in the 0-511
range.
LSD
Loadset directory.
LSTB
Line status table.
LUWID
Logical unit of work
identifier.
lvalue
An expression that represents a data
object that can be both examined and altered.