HP OpenVMS Systems

Subsystem Identifiers and SPAWN?

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The Question is:

 
I am trying to spawn a cms command procedure from a COBOL programm running
 under a subsystem. I'm using the LIB$SPAWN call and setting the SUBSYSTEM bit.
 When LIB$SPAWN is called, the protected subsystem identifier is not passed to
 the spawned process, wh
ich is contrary to the LIB$ RTL REF manual. What do I need to do to resolve the
 problem.
 
EX:
 
01  SUBSYSTEM PIC S9(09)  COMP VALUE 256.
 
CALL "LIB$SPAWN" USING BY DESCRIPTOR "show process/priv"
        omitted
        omitted
        BY REFERENCE SUBSYSTEM
        GIVING CALL_STATUS.
 

The Answer is :

 
  Use of callable CMS would be recommended.
 
  Subsystem identifiers are effectively not passed and not passable
  to DCL procedures, as the identifier exists in the subprocess only
  until the first image is run down.  That image, in the case of a
  DCL spawn, is LOGINOUT.  (As currently implemented within OpenVMS,
  the SUBSYSTEM flag is not particularly useful on a SPAWN operation.
  The SUBSYSTEM flag on $creprc can be more useful, save for cases
  where that mechanism is used to start DCL via LOGINOUT, obviously.)
 
  The approach the OpenVMS Wizard uses tends to be asked on DECnet
  task-to-task or other such interprocess communications with a
  trusted server process, and that server then invokes the necessary
  commands and DCL procedures.  Related general examples include
  topic (159).
 
  The OpenVMS Wizard also makes extensive use of callable CMS.
 

  

     

     
answer written or last revised on ( 25-AUG-2004 )
     
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