Conference azur::mcc

1422.0. "Inter-Thread communication" by CCIIS1::ROGGEBAND (_ �hili��e _) Fri Aug 30 1991 06:10

    Hi,
    
    Are there any plans to provide some sort of inter-thread communication
    mechanism within DECmcc, like messages or semaphores ? This would be
    useful when you have to get two threads to work in co-routine-like
    environement.
    
    Example : in the Ping AM, the main thread creates :
    
    - One thread to send ou the echo request end wait for the response
    - One thread to set up timer.
    
    Theroretically, the timer should start *immediately after* the echo
    request has been sent. In fact, we don't know exactly when it starts,
    particularly under heavy load. Because we have multiple threads, we
    can't synchronize on VMS event flags (we probably wouldn't have enough
    anyway)
    
    If we could pass to either thread the ID of the other so they can
    exchange messages, this would probably give us a better handle on what
    is going on. 
    
    I am sure there are other cases where this kind of feature would be
    useful. But then, perhaps there are arguments against this?
    
    Philippe.

    It's there in MCC/Ultrix as of 1.1 and MCC/VMS as of 1.2.  Look in the
    CMA (DECthreads) doc for info about condition variables.
    

    Thank you Jim. 
    
    Does anyone know if the DECthreads documentation available on the net?
    Or if there is a related conference with pointers ?
    
    �hR. 

  I recently copied these manuals myself.  There are two documents:

  CMA architecture:
 
    clt::clt$library:[cma.specs]cma.ps

  DECthreads Guide:

    BULOVA::DOCD$:[MAGIC_REVIEW.EFT]DECTHREADS.PS

  Happy reading...

                                                              - Jerry