How to use GENERIC jobs

I wanted to expand on the earlier discussion on GENERIC jobs.

The v12.x documentation offers no explanation whatsoever of how to use Generic jobs. To learn a bit more, we have to go back to the v11.2 documentation. There, the page on Generic jobs tells how to specify the agent where a generic job should run: using the &AGENT# variable¹. How does one set the &AGENT#variable?

After several tests, I could not find a way to make Generic jobs work by setting the &AGENT#variable¹ in the pre-process of the generic job. The Generic job will switch correctly to the specified agent only if the &AGENT# variable has been set earlier, during the activation phase of task execution.

The following ways of setting the variable work OK:

• Object variable&AGENT#inVariables & Promptsof the generic job;
  
• Prompt set variable&AGENT#in prompt set added toVariables & Promptsof the generic job;
• Object variable&AGENT#in the task properties of the generic job within its parent workflow;
  
• Object or script variable&AGENT#in the calling task, if the generic job is executed viaACTIVATE_UC_OBJECTwith thePASS_VALUESoption; or
  
• Input variable&AGENT#read from the prompt/read buffer using the:READcommand:
• when passed to the job via a parameter in an EXEC VARA, or
  
• when passed to the job via the set using:PUT_PROMPT_BUFFER in the calling task,
  if the generic job is executed via ACTIVATE_UC_OBJECT.

The following ways of setting the variable do not work:

• Script variable&AGENT#in the pre-process of the job (via :SETcommand);
• Job attributeHOSTin the pre-process of the job (via :PUT_ATTcommand);
• Curly-brace-style VARA object reference in object variable&AGENT#inVariables & Promptsof the generic job²; or
  
• Predefined system or object variable in object variable&AGENT#inVariables & Promptsof the generic job³.

Notes:

1. The v11.2release notesalso mentions the&OVERWRITE_AGENT#variable, but provides no explanation how the two variables differ. (Acommentby Jennifer_Jinhong_34 suggests that the latter variable is related to ARA.) My testing revealed that one can specify the agent where a generic job should run using either the&AGENT#variable or the&OVERWRITE_AGENT#variable. If both are set,&OVERWRITE_AGENT#takes precedence.
   
2. Yes, I actually tried this. I created an EXEC VARA to look up the agent name dynamically. Neither this nor looking it up from a static VARA worked. The following error appeared:
   

   U00000009 '{UC4.RESOLVE_AGENT_GROUP.VARA_EXEC,,1}': Access denied

   Interestingly, VARA object referenceswere correctly resolved inother object variable values— just not in&AGENT#or&OVERWRITE_AGENT#.
3. I also tried passing the agent name via the&ARCHIVE_KEY1#predefined variable. This resulted in
   

   U00007074 Error during generation. A Job object of the type GENERIC may only change to an OS-platform job.

   It seems that variable resolution is simply not performed on the contents of the&AGENT#and&OVERWRITE_AGENT#object variables.