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TASK Statement Parameters

TASk task-code

Specifies a code that identifies the task and is used at runtime by a terminal operator or program to invoke the task.

Task-code must be a one- through eight-character value.

Note: CA ADS mainline dialogs do not require task codes in order to be invoked.

Version is version-number

Differentiates tasks with identical task codes (for example, production and test versions).

Version-number must be an integer in the range 1 through 9,999. The default is 1.

Although multiple versions of a task can exist in the data dictionary, only one version of a task is used by a system at runtime. If multiple ADD TASK statements specify the same task code, at runtime the system uses the one that appears first in the system definition.

AREa acquisition THReshold is

Controls whether the system will accumulate area locks during ready processing of multiple areas for a single database transaction.

The values you specify on the TASK statement will override those specified on the SYSTEM statement.

count

Specifies the number of times, during ready processing, the system will wait on an area lock before it starts to accumulate area locks for a transaction. This value only applies if multiple areas are being readied at one time.

Count must be an integer in the range 1 through 32,767.

Before the threshold count is reached, the system will free locks on areas previously locked by the database transaction if the transaction must wait to place a lock on another area.

Once the threshold is reached, the system will not release existing area locks while waiting for a new area lock.

DEFault

Directs the system to use the values specified in the AREA ACQUISITION THRESHOLD of the SYSTEM statement.

DEFAULT is the default.

OFF

Directs the system not to accumulate area locks until it can acquire all areas needed by a database transaction.

RETry count

Defines a limit on the number of times the system will continue trying to gain access to all areas without accumulating area locks. Count must be an integer in the range 1 through 32,767.

RETry FORever

FORever is the default and directs the system to continue to try to gain access to all needed areas until it successfully acquires all areas or until operating system resource and time limits are exceeded. You should specify the default of FORever unless experience shows that a transaction is not gaining access to areas as needed.

ENAbled

Indicates the task is enabled at system startup and can access the system.

ENABLED is the default when you specify neither ENABLED nor DISABLED in the TASK statement.

DISabled

Indicates the task is not enabled at system startup and is prohibited from accessing the system until the task is enabled.

Note: Users can override the ENABLED/DISABLED parameter at runtime with the DCMT VARY TASK command.

EXTERNAL WAIT is

Specifies the length of time the system waits for an external request for the named task before abnormally terminating the task.

Note: Users can override the EXTERNAL WAIT parameter at runtime with the DCMT VARY TASK command.

SYStem

Directs the system to use the external wait time specified on the SYSTEM statement. A value of 0 is synonymous with SYSTEM.

external-wait-time

Specifies the amount of time, in wall clock seconds, the system is to wait for an external request for the named task.

External-wait-time must be an integer in the range 0 through 32,767.

FOREVER/NO

Directs the system not to terminate the task based on an external wait time.

INActive interval is

Specifies the amount of time the system permits a DC task or external user session to wait for a resource before abnormally terminating the task.

Note: Users can override this parameter at runtime with the DCMT VARY TASK STALL command.

inactive-wait-time

Specifies the inactive interval in wall-clock seconds.

Inactive-wait-time must be an integer in the range 1 through 32,767. The specified interval overrides the INACTIVE INTERVAL parameter of the current SYSTEM statement.

SYStem

Specifies the system will terminate the task based on the SYSTEM statement INACTIVE INTERVAL parameter specification.

SYSTEM is the default when you omit the INACTIVE INTERVAL parameter from the TASK statement.

OFF

Specifies the system will not terminate the task based on an inactive interval.

Note: For more information about the inactive interval, see Abend Detection and Timed Functions.

INPut

Specifies the terminal input buffer can contain data along with the task code. You should specify INPUT if the program invoked by the task requests a transfer of data from the terminal buffer to the task via a READ TERMINAL, READ LINE TERMINAL, or MAPIN request, as its first I/O operation, or if an external task permits the terminal operator to specify parameters or commands following the task code (for example, DCUF SHOW USERS).

INPUT is the default when you specify neither INPUT nor NOINPUT in the TASK statement.

NOInput

Specifies the terminal buffer can contain only the task code. You should specify NOINPUT if the program invoked by the task does not request a transfer of data from the terminal buffer to the task as its first I/O operation or if an external task does not permit the terminal operator to specify parameters or commands following the task code (for example, BYE).

INTernal

Specifies the task can be invoked internally only. A task is invoked internally when an executing program specifies the task code in an ATTACH or DC RETURN NEXT TASK CODE request.

EXTernal

Specifies the task can be invoked either externally or internally. A task is invoked externally when the user enters a task code in response to the system prompt.

EXTERNAL is the default when you specify neither INTERNAL nor EXTERNAL in the TASK statement.

INVokes program program-name

Specifies the name of the initial program to be invoked by the system for the task.

Program-name must be the name of a program previously defined in the data dictionary.

The INVOKES PROGRAM parameter is required in ADD TASK statements.

Note: Users can override this parameter at runtime with the DCMT VARY TASK PROGRAM command.

Version version-number

Verifies the specified version of program-name exists in the data dictionary and is associated with the current system. This parameter has no effect on runtime operations.

Version-number must be an integer in the range 1 through 9,999. The default is 1.

LIMit is

Specifies limits on system resources held by tasks. You can code one LIMIT parameter for each resource type.

Note: To enforce limits on a task's resources, task statistics must be collected. You use the STATISTICS parameter of the system generation SYSTEM statement to enable the collection of task statistics. For more information about runtime considerations for task resource limits, see the CA IDMS System Operations Guide.

Note: Users can override this parameter at runtime with the DCMT VARY TASK command.

CALl

Limits the number of system service calls (for example, OBTAIN CALC) issued by an online task. When you specify CALL, limit must be an integer in the range 1 through 2,147,483,647.

DBIo

Limits the number of database I/O operations (reads and writes) performed by online task. When you specify DBIO, limit must be an integer in the range 1 through 2,147,483,647.

LOCk

Limits the number of record locks allocated to an online task during the life of the task. When LOCK is specified, limit-n is an integer in the range 1 through 2,147,483,647.

STOrage

Limits the amount of storage, in 1K bytes, that an online task can hold at one time. When you specify STORAGE, limit must be an integer in the range 1 through 16,383.

limit

Directs the system to use the specified limit for the indicated resource.

SYStem

Directs the system to use the limit for the resource defined in the SYSTEM statement LIMIT FOR ONLINE TASKS parameter.

SYSTEM is the default when you omit the LIMIT parameter from the TASK statement.

OFF

Directs the system not to limit the task's use of the named resource.

LOCation is

Specifies the memory location from which the DC/UCF system loads programs and allocates storage for the named task.

Note: Users can override this parameter at runtime with the DCMT VARY TASK LOCATION command.

BELow

Indicates that programs are loaded into 24-bit program and reentrant pools, and storage is allocated from 24-bit storage pools.

BELOW is the default when you omit the LOCATION parameter from the TASK statement.

ANY

Indicates that programs are loaded into 24-bit or 31-bit program pools and storage is allocated from a 24-bit or a 31-bit storage pool:

  • The system chooses a program pool or reentrant pool by checking the program RMODE and REENTRANT/QUASIREENTRANT/NONREENTRANT specification
  • The system chooses a storage pool by checking the type of storage specified in the user GET STORAGE request

Note: For more information about how the system selects a program pool or a storage pool at runtime, see the CA IDMS System Operations Guide.

MAP

Specifies the task performs a mapout automatically upon initiation. The DC/UCF user program will not perform this I/O operation.

NOMap

Specifies the task will not perform a mapout automatically upon initiation. If you specify NOMAP, the task is not dedicated to a mapout operation and the task's initial program, as specified in the INVOKES PROGRAM parameter, does not have to be a map.

NOMAP is the default when you specify neither MAP nor NOMAP in the TASK statement.

MAXimum CONcurrent threads is

Limits the number of threads that can be active concurrently for the task. When the limit is exceeded, a message is routed to the terminal.

Note: Users can override this parameter at runtime with the DCMT VARY TASK MAXIMUM CONCURRENT command.

thread-count

Specifies the maximum number of concurrent threads.

Thread-count must be an integer in the range 1 through 32,767.

OFF

Indicates the system will not limit the number of concurrent threads for the task.

OFF is the default when you omit the MAXIMUM CONCURRENT THREADS parameter from the TASK statement.

ON COMmit

Specifies options that control commit behavior. These options apply only to commit operations in which the database session remains active.

SYSTEM

Specifies that the commit behavior for the task should default to that specified for the system.

WRIte COMT

Specifies that a COMT journal record should be written.

WRIte ENDJ

Specifies that an ENDJ journal record should be written.

NEW ID

Specifies that a new local transaction ID should be assigned to the next transaction associated with the database session.

RETain ID

Specifies that the existing local transaction ID should be assigned to the next transaction associated with the database session.

ON ROLlback continue

Specifies options that control rollback behavior. These options apply only to rollback operations in which the database session remains active.

SYSTEM

Specifies that rollback behavior for the task should default to that specified for the system.

RETain ID

Specifies that following a rollback, the current local transaction ID should be assigned to the next transaction associated with the database session.

NEW ID

Specifies that following a rollback, a new local transaction ID should be assigned to the next transaction associated with the database session.

PRINt key is

Overrides the system-wide print-screen key assignment (specified by the PRINT KEY parameter of the system generation SYSTEM statement) for the named task.

PAn

Identifies a program attention key. N must be the integer 1, 2, or 3.

PFn

Identifies a program function key. N must be an integer in the range 1 through 24.

Note: The transfer control facility (TCF) uses PF3 and PF9 for the TERMINATE and SUSPEND functions. For tasks that execute under TCF, do not specify PF3 or PF9 as the print-screen key.

SYSTEM (default)

Indicates the print-key assignment specified in the PRINT KEY parameter for the current SYSTEM statement is used.

SYSTEM is the default when you omit the PRINT KEY parameter from the TASK statement.

OFF

Disables the print-screen facility for the task.

Note: For more information about assigning a print-screen key, see the description of the SYSTEM statement PRINT KEY parameter in SYSTEM Statement.

PRIority is task-priority

Specifies the dispatching priority for the online task.

Task-priority must be an integer in the range 0 (lowest priority) through 240 (highest priority). The default is 100.

For more information about the dispatching priority of certain tasks, see Specifying a TASK PRIORITY

Note: Users can override this parameter at runtime with the DCMT VARY TASK PRIORITY command.

Note: The PRIORITY clause has no impact on tasks initiated as a result of an ATTACH statement in a COBOL or PL/I program or a #ATTACH macro in an Assembler program.

PROduct code is product-code

Identifies a product and related task codes by a generic name.

Product-code must be a one- through eight-character generic name of the product associated with the task.

When using this parameter in conjunction with TCF, product-code must be one of the following values: IDD, OLM, SCHEMA, SSC, SYSGEN, OLQ, ADSA, ADS2, or ADSC.

PROtocol is

Specifies the response protocol to be used by the task when communicating with terminals associated with a VTAMLIN type line.

DEFresp

Specifies the task is to use definite response protocol. The terminal from which the task is executed must respond with a completion status when a terminal write is requested from the DC/UCF system.

DEFRESP is the default when you omit the PROTOCOL parameter from the TASK statement.

Printers run with definite response protocol regardless of the protocol specification for the task.

Note: If you specify DEFRESP the VTAM line definition statement, then you must specify EXPRESP on the task definition statement for each individual task.

EXPresp

Specifies the task is to use exception response protocol. Exception response protocol reduces transmission time because terminals are not required to respond with a completion status when a terminal write is requested from the DC/UCF system.

Note: If you specify EXPRESP on the VTAM line definition statement, then all tasks will run using the exception response protocol, and the specification you make here has not effect.

QUIesce wait is

Specifies if the system permits the task to wait for a quiesce operation to terminate; and if waiting is permitted the amount of time the task waits before it is abnormally terminated.

Note: Users can override the QUIESCE WAIT parameter at runtime with the DCMT VARY TASK command.

SYStem

Specifies the quiesce wait time for the task is determined by the quiesce wait setting for the system. This is the default.

quiesce-wait-time

Specifies the quiesce wait interval in wall-clock seconds. quiesce-wait-time must be an integer in the range 1 through 32,767. The specified value overrides the QUIESCE WAIT parameter of the current SYSTEM statement.

FORever

Directs the system not to terminate tasks based on quiesce wait time. FORever overrides the QUIESCE WAIT parameter of the current SYSTEM statement.

NOWait

Specifies tasks do not wait for quiesce operations to terminate and instead, receive an error indicating an area is unavailable. For navigational DML requests, this results in an error-status value of 'xx66'. NOWait overrides the QUIESCE WAIT parameter of the current SYSTEM statement.

RESource timeout

Defines the task's resource timeout interval and resource timeout program used for pseudo-conversational transactions.

Note: Users can override this parameter at runtime with the DCMT VARY TASK command.

INTerval is

Specifies the amount of time the system is to permit a terminal to be inactive (that is, have no task executing) before invoking the terminal resource program to handle (for example, delete) the resources owned by the inactive terminal.

resource-timeout-interval

Specifies the resource timeout interval in wall-clock seconds.

Resource-timeout-interval must be an integer in the range 1 through 32,767.

SYStem

Directs the system to use the INTERVAL IS value specified in the RESOURCE TIMEOUT parameter of the current SYSTEM statement.

SYSTEM is the default when you omit the RESOURCE TIMEOUT INTERVAL parameter from the TASK statement.

FORever/OFF

Disables the resource timeout facility.

FOREVER and OFF are synonyms and can be used interchangeably.

PROgram is

Identifies the program the system will invoke to handle the resources owned by an inactive terminal following the expiration of the resource timeout interval.

resource-timeout-prog-name

Explicitly specifies the resource timeout program.

Resource-timeout-prog-name must be the name of a program previously defined in the data dictionary with a PROGRAM statement.

Version is version-number

Qualifies the named program with a version number.

Version-number must be an integer in the range 1 through 9,999. The default is 1.

SYStem

Directs the system to use the value specified in the PROGRAM IS option of the RESOURCE TIMEOUT parameter in the current SYSTEM statement.

SYSTEM is the default when you omit the RESOURCE TIMEOUT PROGRAM parameter from the TASK statement.

Note: For more information about the resource-timeout mechanism, see Abend Detection and Timed Functions.

SAVe

Indicates that current terminal output associated with the task when the terminal on which the task is executing receives a write-direct-to-terminal data stream.

Note: With line-mode I/O, terminal output is always saved unless a program specifies the NOBACKPAGE parameter.

NOSave

Indicates that the system will not save the contents of the terminal screen before writing a write-direct-to-terminal data stream.

NOSAVE is the default when you specify neither SAVE nor NOSAVE in the TASK statement.

Note: Users can override the SAVE/NOSAVE specification at runtime with the DCMT VARY TASK SAVE/NOSAVE command.

TCF task is tcf-task-code

Specifies the named task is eligible to run under the transfer control facility (TCF).

Tcf-task-code must be a previously defined task code that invokes the TCF control program (RHDCUMBR).

Version is version-number

Differentiates identical TCF task codes (for example, production and test versions).

Version-number must be an integer in the range 1 through 9,999. The default is 1.

TRAnsaction SHAring is

Specifies options that control transaction sharing.

OFF

Specifies that transaction sharing is initially disabled when a task of this type is initiated.

ON

Specifies that transaction sharing is initially enabled when a task of this type is initiated.

SYStem

Specifies that the initial transaction sharing setting for a task is the value specified in the TRANSACTION SHARING clause of the SYSTEM statement. SYSTEM is the default if you omit the TRANSACTION SHARING parameter from the TASK statement.

Note: For more information about transaction sharing, see the CA IDMS Database Administration Guide.

More information

SYSTEM Statement

Abend Detection and Timed Functions