The Y (Status Interrogate) system command returns several types of information about a process, including the mix number, usercode, program name, and stack state. In the following example, the stack state is WAITING ON AN EVENT:
Status of Task 3251\4441 AT 16:15:28 Program name: *OBJECT/ED ON DOCPK Priority: 50 Origination: SA154/CANDE/3 (LSN 288) MCS: SYSTEM/CANDE Usercode: JASMITH Chargecode: 6825 Stack State: Waiting on an event
If the process is a library, then the Y display also includes a list of the processes linked to the library. Refer to Determining Which Clients Are Linked to a Library in Using Libraries.
The following are explanations of the STACK STATE values shown in Process States:
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The process is currently bound to a processor. That is, it is actually being processed rather than being in any type of waiting state. You can see this state displayed only on a multiprocessor system, because on a single processor system, the CONTROLLER independent runner has to take over the only processor to execute the Y command.
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Frozen
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Holding
The process is waiting on interrupts. This type of waiting is described in Using Events and Interlocks.
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Ready
The process is in the ready queue and will proceed as soon as a processor is available. It is not unusual for a process to be in this state, because each central processor on the system can be executing only one process at a time, and the mix can contain many processes. The priority of a process can affect the amount of time it spends in the ready queue; refer to Controlling Processor Usage.
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Scheduled
The system is delaying initiation of the process for any of various reasons. For information about process scheduling, refer to Preventing Process Scheduling later in this section.
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Selected
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To be continued
This value indicates a process that has initiated a synchronous task that has not yet completed, or a process that has executed a CONTINUE statement and is waiting on its coroutine.
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Waiting on an event
If no RSVP line appears in the Y command output, then this value means the process is waiting for an I/O operation to be completed or for a particular event to be caused. For a general discussion of events, refer to Using Events and Interlocks.
If an RSVP line appears in the Y command output, then the WAITING ON AN EVENT value means that the process is waiting on an event that might require operator intervention. The RSVP line lists system commands that might be helpful responses to the situation. For more information about responding to waiting entries, refer to the System Operations Guide.
If the process is taking a program dump, executing a SORT procedure, or scrubbing disk areas, then the Stack State value includes a second component that states Programdumping, Sorting, scrubbing disk areas, or some combination of them. The following example shows the output for a process that is taking a program dump:
Status of Task 6408/6513 at 16:39:09 Program name: *OBJECT/ED ON SYS00 Priority: 50 Origination: OCDWH_1/CANDE/2 (LSN 295) MCS:SYSTEM/CANDE Usercode: DEBS Chargecode: 6893 Stack State: Waiting on an event, Programdumping Display: ED:OPERATOR DSED @ (47312200)
