Execute a CICS business transaction services activity synchronously without context-switching.
Description
LINK ACTIVITY executes a CICS business transaction services activity synchronously with the requestor, with no context-switching. The activity must previously have been defined to BTS.
LINK ACTIVITY causes BTS to invoke the activity and send it an input event. If the activity is in its initial state—that is, if this is the first time it is to be run, or if it has been reset by a RESET ACTIVITY command—CICS® sends it the DFHINITIAL system event. If the activity is not in its initial state, the input event must be specified on the INPUTEVENT option.
- If it is running as the activation of an activity, its own child activities. It can link to several of its child activities within the same unit of work.
- The activity it has acquired, by means of an ACQUIRE ACTIVITYID command, in the current unit of work. (Note, however, that if the program is running as the activation of an activity, it must use a RUN, not a LINK, command to activate the activity it has acquired.)
To check the response from the activity, the CHECK ACTIVITY command must be used. This is because the response to the request to activate the activity does not contain any information about the success or failure of the activity itself—only about the success or failure of the request to activate it. Typically, the CHECK command is issued immediately after the LINK command.
No context-switching
- In the same unit of work as the requestor
- With the transaction attributes (TRANSID and USERID) of the requesting transaction.
In other words, there is no context-switch. To invoke an activity synchronously with context-switching—that is, in a separate UOW from that of the requesting transaction and with the TRANSID and USERID attributes specified on its DEFINE ACTIVITY command—use the RUN ACTIVITY SYNCHRONOUS command.
If performance is more important than failure isolation, recoverability, and security, use LINK ACTIVITY rather than RUN ACTIVITY SYNCHRONOUS.
Options
- ACQACTIVITY
- specifies that the activity to be run is the one that the current unit of work has acquired by means of an ACQUIRE ACTIVITYID command.
- ACTIVITY(data-value)
- specifies the name (1–16 characters) of the activity to be run. The name must be that of a child of the current activity.
- INPUTEVENT(data-value)
- specifies
the name (1–16 characters) of the event that causes the activity to
be attached.
You must not specify this option if the activity is in its initial state; that is, if this is the first time it is to be run, or if it has been reset by a RESET ACTIVITY command. In this case, CICS sends the activity the DFHINITIAL system event.
You must specify this option if the activity is not in its initial state; that is, if it has been activated before, and has not been reset by a RESET ACTIVITY command.
If you specify INPUTEVENT, for the LINK command to be successful the activity to be attached must have defined the named event as an input event.
Conditions
- 107 ACTIVITYBUSY
- RESP2
values:
- 19
- The request timed out. It may be that another task using this activity-record has been prevented from ending.
- 109 ACTIVITYERR
- RESP2
values:
- 8
- The activity named on the ACTIVITY option could not be found.
- 14
- The target activity is not in the correct mode to process the specified event option. If the INPUTEVENT option was not specified, the activity must be in INITIAL mode. If the INPUTEVENT option was specified, the activity must be in DORMANT mode.
- 111 EVENTERR
- RESP2
values:
- 7
- The event named on the INPUTEVENT option has not been defined by the activity to be run as an input event; or its fire status is FIRED.
- 16 INVREQ
- RESP2
values:
- 4
- The ACTIVITY option was used to name a child activity, but the command was issued outside the scope of a currently-active activity.
- 21
- The activity is suspended, and therefore cannot be run synchronously.
- 24
- The ACQACTIVITY option was used, but the issuing task has not acquired an activity.
- 40
- The program that implements the activity is remote.
- 44
- A LINK has been attempted to a Java program, but the JVM pool is disabled.
- 45
- A LINK has been attempted to a Java program, but the JVM profile cannot be found.
- 46
- A LINK has been attempted to a Java program, but the JVM profile is not valid.
- 47
- A LINK has been attempted to a Java program, but the system properties file cannot be found.
- 48
- A LINK has been attempted to a Java program, but the user class cannot be found.
- 49
- The shared class cache is STOPPED and autostart is disabled, so a Java program requesting use of the shared class cache cannot be executed.
- 17 IOERR
- RESP2
values:
- 29
- The repository file is unavailable.
- 30
- An input/output error has occurred on the repository file.
- 100 LOCKED
- The request cannot be performed because a retained lock exists against the relevant record on the repository file.
- 70 NOTAUTH
- RESP2
values:
- 101
- The user associated with the issuing task is not authorized to run the activity.
- 27 PGMIDERR
- RESP2 values:
- 1
- A program has no installed resource definition and either program autoinstall was switched off, or the program autoinstall user program indicated that the program should not be autoinstalled.
- 2
- A program is disabled.
- 3
- A program could not be loaded because:
- This was the first load of the program and the program load failed, usually because the load module could not be found.
- This was a subsequent load of the program, but the first load failed.
In order to reset the load status the load module must be in the DFHRPL or dynamic LIBRARY concatenation, and a SET PROGRAM NEWCOPY will be required.
- 21
- The program autoinstall user program failed either because the program autoinstall user program is incorrect, incorrectly defined, or as a result of an abend in the program autoinstall user program. Program autoinstall is disabled and message DFHPG0202 or DFHPG0203 written to the CSPL.
- 22
- The model returned by the program autoinstall user program was not defined to CICS, or was not enabled.
- 23
- The program autoinstall user program returned invalid data.
- 24
- Define for the program failed due to autoinstall returning an invalid program name or definition.
