HP OpenVMS Systems

POSIX.4 aio calls; mixing ASTs and threads?

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The Question is:

 
Mr Wizard,
 
     Currently, it is NOT recommended that async I/O and Pthreads
     be mixed (wiz_3443 amongst others).
 
     Q1) Is this limitation likely to go away. I would add, that many people
            argue that it is very inefficient to use SELECT for IP based
            Servers, yet with this limitation in place, you would have little
            choice but to use SELECT if you were to use PTHREADS.
 
     Q2) Is the Wizard aware of any intention to actively support
             POSIX.4 - this interface is the Real-Time Interface for
             UNIX (aio_XXX).
 
thanks inadvance
 
-Fred
 

The Answer is :

 
  The difficulties involved in mixing DECthreads and ASTs are inherent in
  the internal implementations of DECthreads and of ASTs.
 
  The choice of implementation mechanisms varies by application.  For some,
  the OpenVMS Wizard would prefer direct use of ASTs, multiple processes,
  and (as needed) shared memory or other communications mechanism.
 
  The aio POSIX.4 routines are part of the existing POSIX environment, and
  are also part of the new DII COE work.
 
 

  

     

     
answer written or last revised on ( 5-FEB-2001 )
     
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