Re: allow multiple threads in interactive job

The reason interactive jobs were not enabled to support multi-threaded
applications is that large pieces of the internal OS which they use are not
capable of handling multiple threads.  The cost to multi-thread enable the
whole system was huge.  Therefore the decision was made (way back when this
was orginally done) to support multiple threads in those environments that
did not require an entire rewrite of major portions of the internals of the
OS.

Patrick Botz



                                                                           
             Steve Richter                                                 
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             02/11/2005 11:15                                      Subject 
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On Fri, 11 Feb 2005 10:40:13 -0600, Bruce Vining <bvining@xxxxxxxxxx>
wrote:
>
>
> >From the V5R3 Information Center:

thanks Bruce.

> ...Interactive and communication jobs do no provide multithread-capable
> support.

that stinks!  I was going to try and implement a message loop style of
programming in an interactive job.  The idea being to use the C record
io functions for display file i/o in a 2nd thread of the job.  A 3rd
thread might wait on an object lock.  or do a dlyjob. I was thinking
you could even use RCVJRNE to place a message on the message loop
queue when a record was added to a file.  All the threads then feed
their input to the data queue that the interactive job receives from
as its message loop.

Was not sure if I could cancel a display file read in the background
thread without using INVITE or not.

Too bad IBM places all these restrictions on their system.

thanks,

-Steve
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