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PHP CLI hangs on Ctl+Break

10 Sep 2010 10:08 #62 by steveh
Thank you again. Running the component as a Service solved the problem for me. I now runs as expected, except that processor usage for eopcdal.exe seeems quite a bit a bit higher than I would have expected for half second interrogations. I will run it for a while and see if I can figure out why.

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10 Sep 2010 07:25 #60 by support
Regarding the differences in types of COM servers, this is covered in the Concepts document (<a href=" under "COM Registration and Server Types", and the specific chapter is also online here:
The In-process server options runs the component inside calling application's process, as a DLL. The Local server and Service options run in a process separate from the calling app. The Local server's process lifetime is controlled by the DCOM infrastructure only (it is started or stopped depending on whether any objects are needed from the component), whereas with the Service you also get the usual control capabilities available for Windows services, including various startup types: Automatic, Manual, Disabled, etc.).
When your calling application is a service, I recommend to register EasyOPC-DA component either as In-process server , or as a Service. The reason why the Service is greyd out initially is explained in the article I referred to; you basically need to run
eopcdal /Service

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09 Sep 2010 23:39 #58 by steveh
Thanks for the quick response. Always a good sign.
Running as a Local Server seems to have solved the problem. I can now Ctrl+Break and the prompt returns. Very good.
Can you point me please to some words on the real differences between running in-process, as a local server, and as a service? When I use this software in anger it will be operating in an environment where the calling application is running as a service, with nobody logged on to the computer. My original thought was that I should run the EasyOPC runtime as a service, but that option was greyed when I started playing. Is it possible to test it as a service?

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09 Sep 2010 14:53 #57 by support
Thanks for your post.
This precise problem is new to me, but there is a known issue that is very similar and has very likely the same root cause. It happens when Ctrl+Break or Ctrl+C is pressed from within a Windows Script Host running e.g. VBScript or JScript that is using QuickOPC-COM, AND the component is registered as COM in-process server. This situation is a "deadly mix" that creates a requirement that is very difficult, if possible at all, to resolve, because the component has background-running threads that can be in ANY state when this asynchronous signal is sent - and they all need to gracefully shut down in a coordinated manner. I have been trying to resolve it for some time without success.
There may be a workaround, though. Simply use the out-of-process option (Local Server). To do so, run the EasyOPC-DA Options utility, and on the System Parameters tab, uncheck the "COM Registration: In-process server" box, and make sure that the "Local server" box is checked, as on the attached picture.

If for some reason this does not help, I may have another try at resolving the core reason, but as I explained, there is a great deal of complexity in it.

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09 Sep 2010 12:14 #56 by steveh
I am evaluating QuickOPC-COM in a PHP environment. Generally it looks very good and I want to use it in anger - but:
I have a PHP script running as a CLI instance in a XP command shell. The script is happily reading and displaying a dozen values as a ReadMultipleItems call every half second in an infinite loop.
Unfortunately, when I stop the script with a Ctrl+Break or a Ctrl+C the shell just hangs indefinitely and does not return to the prompt.
Many other scripts I have used in PHP CLI do exit in a controlled manner with a Ctrl+Break. This is the first time I have had this problem, and it is the first time I have used QuickOPC.
Can you think of any reason why a Ctrl+Break would hang the shell? Perhaps something in the runtime closure?
Hope you can help. This is the last hurdle before a purchase.

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