asynchronous ocean coding

I dragged and dropped 'script.ocn' and 'hello_world.ocn' here, but I can't tell if they have been successfully uploaded. If they are still not, please let me know.

No, they've not been attached. I think I'd need to see the code to understand what you're trying to do. Not really sure what you mean by having this watchdog function watch over the math() function - they are in separate processes, so not sure what would be watching what.

Try using Insert->Image/Video/File and then loading the file from the computer. it should show up in the post before you post so it should be fairly obvious that it worked. Drag and drop is mainly for images, not for other files.

Andrew.

Unfortunately the uploading system seem to be unfriendly to me

Let me try to do it the stupid way

script.ocn:

let( ( cid)
cid=ipcBeginProcess("ocean -replay ./hello_world.ocn")
printf("------------------I am asynchronous--------------\n") ;
); end let

hello_world.ocn:

procedure(hello_world()
let( (i)
i=0 ;
while( i<5
printf("------------hello world-----------\n")
i=i+1 ;
);end while
);end let
);end procedure
hello_world()

Somehow I can't type in sleep(2) after i=i+1;

Whenever I tried to do so, there is a message "An error occurred. Please try again or contact your administrator". And what is strange is that I can type in sleep(2) here.

Please add that to the code.

Not entirely sure the point of this, because the printed information won't appear anywhere in the background process. So I modified script.ocn to have a data handler to print that. I also unset CDS_MPS_SESSION - in general when starting one virtuoso (or ocean) from another, you should do this as otherwise they can end up interfering with each other (MPS is the mechanism via which remote procedure calls work in Virtuoso, and otherwise they share the same session and you end up with a clash of services from the two virtuosos that are running).

https://community.cadence.com/cfs-file/__key/communityserver-discussions-components-files/48/script.ocn

I also altered hello_world.ocn to flush the output buffer, and also used ipcSleep() instead of sleep. I think your problem was probably caused by the MPS (not sure) clash, but in general ipcSleep is preferable to sleep as it allows data handlers to be executed (not that you have any in the child process, but just in case).

https://community.cadence.com/cfs-file/__key/communityserver-discussions-components-files/48/hello_5F00_world.ocn

Not sure why you had a problem with the file upload - it appears to have worked fine for me.

Regards,

Andrew.

HI Andrew,

Did you observe "------------------I am asynchronous--------------" in the output? I was expecting it to see it in the output, but it did not. 

I think my question is:

1. Was printf("------------------I am asynchronous--------------\n") ; actually executed before hello_world.ocn finished?

2. Was there a limitation that whatever code after ipcBeginProcess has the limitation that it cannot output to stdout?

Yes, it appeared immediately after the ipcBeginProcess, and then I see all the output log info from the child ocean/virtuoso process, and then finally I see all the hello world statements (which appeared at 2 second intervals).

The ipcBeginProcess returns immediately (it doesn't wait for the child to complete - which doesn't actually complete in this case anyway as there's no exit in the hello_world.ocn), and then the code continues as normal after it returns. There's no limitation here at all - not sure how you came to that conclusion.

Regards,

Andrew.

(I tried pasting in the output but the forum server probably needs restarting as it wouldn't work - probably your attempt to upload the files is related - we're awaiting changing to a new more reliable server)

Yes, it appeared immediately after the ipcBeginProcess, and then I see all the output log info from the child ocean/virtuoso process, and then finally I see all the hello world statements (which appeared at 2 second intervals).

The ipcBeginProcess returns immediately (it doesn't wait for the child to complete - which doesn't actually complete in this case anyway as there's no exit in the hello_world.ocn), and then the code continues as normal after it returns. There's no limitation here at all - not sure how you came to that conclusion.

Regards,

Andrew.

(I tried pasting in the output but the forum server probably needs restarting as it wouldn't work - probably your attempt to upload the files is related - we're awaiting changing to a new more reliable server)

Thanks for the confirmation. After examining stdout again, I found "------------------I am asynchronous--------------", somewhere buried in the pages of stdout from the flow enabler.

Currently, it seems this ipcBeginProcess is working as I expected and I can continue.