TCBS

Type

OMEGAMON Minor command

Description

Figure 1. Typical output for a TCBS minor command

Displays the current TCB structure for the target user. This next screen shows a typical TCBS display.

 PEEK  PAYROLL  ASID=25, collected at 15:39:39
==============================================================================
 tcbs   Program  Mother   Daughter  Sister  Jobstep
+       IEAVAR00          IEESB605           (SELF) (Region Control Task)
+       IEESB605 IEAVAR00 IEFIIC    IEAVTSDT (SELF) (Started Task Control)
+       IEFIIC   IEESB605 PAY1               (SELF) (Initiator)
+       PAY1     IEFIIC                      (SELF)
+       IEAVTSDT IEAVAR00                    (SELF) (SVC Dump Task)
==============================================================================

This is a typical TCB structure for a batch job.

The following fields appear in the TCB display:

Program: The load module name of the most recently created RB for each TCB. In this case, PAY1 refers to the name specified in the EXEC PGM= parameter.
Mother Daughter Sister: Program names for the mother, daughter, and oldest sister TCBs of the Program TCB.

Note that most address spaces on this level point to themselves as the Jobstep TCB. You can use this information to easily construct a picture of the current TCB structure, as illustrated in the following figure.

The TCB structure associated with the previous display:

If you place an A in the label field of TCBS (so: ATCBS), OMEGAMON displays the actual TCB address under each TCB program name. This information may be useful if several TCBs in the same step invoke the same program.

If you place an X in the label field of TCBS (so: XTCBS), two extra lines appear for each TCB. The first line shows the storage protect key for the TCB and indicates whether the address space is APF authorized.The second line indicates whether it is DISPATCHABLE or NON-DISPATCHABLE. For those TCBs that cannot be dispatched, a short explanation appears to indicate which non-dispatchability bit was found set.

For example, the following message indicates that the TCB is merely waiting to post an ECB.

NON-DISPATCHABLE: TOP RB WAITING ON ECB

This is by far the most common reason for a TCB to be non-dispatchable.

You may optionally specify a 2-digit number in the operand field of TCBS to suppress the display of the first nn TCBs. This number is useful if all of the TCBs do not fit on one screen.

If the job being PEEKed has many TCBs, you may need to increase the maximum number of control blocks tested with the LOOPCOUNT keyword of the .SET command.

Related Information

Minor of: PEEK

Minors that collect data about address spaces: AMAP, DATA, DDNS, JOBS, MODS, STEP, and SUBP