I am integrating CLIPS expert system following APG docs, Thanks for the great docs, I am successful at integrating CLIPS to my C++ project, My Application runs continuously and feed the Facts to CLIPS system using EnvAssert method and invoke EnvRun, everything works fine until i receive this error.
[PRNTUTIL7] Attempt to divide by zero in / function.
[DRIVE1] This error occurred in the join network
Problem resides in associated join
Of pattern #1 in rule RULE-1
[PRCCODE4] Execution halted during the actions of defrule RULE-2.
Once i receive this error, further Assert is working but Run seems not working, but i am sure there are definite matching rules are available but still no rules are fired on next Run.
I understood the error and i can fix it, but i cannot understand the behavior. So i tested it in CLIPS console, there when the error was reported consecutive Run seems working as i expected, but not in case of my application, i want to know the underlying difference.
Ref pseudo-code of Application :
<code to create and initialize CLIPS environment>
EnvReset()
While(true)
{
<my code to get facts>
EnvAsset(Fact)
EnvRun(-1)
<my code to receive the generated result facts>
}
Note: I dont call RESET before every RUN.
Fixes for resetting the error flags for API calls have been checked into the subversion repository on sourceforge: https://sourceforge.net/p/clipsrules/code/HEAD/tree/branches/
Related
We're currently facing some issues trying to start a Service in Windows, which is an executable file and the output of a compiling process using .NET framework for C++ (Windows\Microsoft.NET\Framework\v2.0.50727).
We are able to compile, start and execute the exact same service in our DEV Environment, which consists of Windows 7 installed in Virtual Box with VisualStudio2005 (it's old software, I know...).
When we do it in our Test environment, we get a timeout error when trying to start the Service (1053: The Service Did Not Respond to the Start or Control Request in a Timely Fashion.). The server is running WindowsServer 2008 R2 Standard. We already tried to change the timeout time, without success. We also compiled the source code using the same Visual Studio 2005 SW and although we were able to compile it successfully we are still getting the same timeout message.
We are currently trying to understand what's objectively causing the different behaviour. The most obvious difference is the windows version, naturally, but since the compilation output appears identical and there are no errors during the compilation process in both environments and both output logs are identical as well we are running low on ideas to identify and validate objective differences. Our latest approach consists in trying to understand if by using Dependency Walker (dependencywalker.com) we are able to identify any issue regarding DLLs (we also checked if there is any corrupt DLL or system file in the environment and there isn't any, using the windows command for it). We're also checking some of the suggestion made on the following post: Error 1053 the service did not respond to the start or control request in a timely fashion.
Any one faced a similar issues? If so, can you suggest any kind of approach to identify the reason why the service isn't staring, other than the ones here mentioned?
Thanks in advance.
We ended up extending the timeout time regarding Service startup in Windows to 10 minutes followed by the necessary restart and we managed to start the service normally and almost immediately, which makes us think that the timeout time was never really an issue here. Although we haven't been able to pinpoint the exact cause we are still inclined to think that it was a Windows/Server related issue.
i use google test and google mock.
There is a mock object on which i expect a method call OnConnectionError() which notifies the absl::Notification object done 3 times.
absl::Notification done;
EXPECT_CALL(*client, OnConnectionError(::testing::_)).Times(3)
.WillRepeatedly(Notify(&done));
bool result = client->ConnectToServer("localhost", 5000, 2);
done.WaitForNotificationWithTimeout(absl::Duration(absl::Seconds(30)));
The method client->ConnectToServer has a loop which results in the repetitive call of OnConnectionError, which is fully fine and the desired behaviour.
On Windows the unit test passes fine. When jenkins runs it on ubuntu, it aborts the whole test run (not only failing one test!!) with the following output.
[notification.cc : 32] RAW: Notify() method called more than once for Notification object 0x7ffffde87320
Is it not allowed to call the Notification object multiple times? Why does the test success on Windows and aborts on ubuntu?
many thanks for your support!
I found the answer by my self:
I reviewed the relevant source of google abseil. In notification.cc i found the relevant error message. The respective source part is surrounded by a
#ifndef NDEBUG
I edited the CMakeLists file in order to rebuild it in Release mode by adding the line set(CMAKE_BUILD_TYPE Release), so the NDEBUG flag is defined on compile time.
As a consequence not directly connected to this issue, i refactored the code under test in a way, to avoid the loop, which notifies the absl::Notification object multiple times, since this issue showed me that there is a demand for improving the code.
I need suggestion about YAMI library . I have a system which receives Json string from external interface and parse that received string and send that message to internal ip address for the required action.
The exchange of messages within the internal ip address has been taken care by Yami library. everything works fine but occasionally it displays yam i/o error and system doesn't response unless it is restarted.
The whole software is written in C++ and C and development os is fedora 11.
I have tried to investigate the problem but I am bit clueless as I have not found much help on internet and my testing method doesn't work.
its strange that system works for few hours and then crash . For example If I leave system idle for half an hour and then try to send message via external interface it crashes producing yami i/o error or even while sending continuos command it crashes.
Any help or suggestion will be of great help.
Thanks and regards,
Sam
It looks like this exception is from a core::io_error result which is translated to a runtime exception by details::translate_result_to_exception(). Most of this error originates from the source code in yami/posix in your case.
What you have to do now is figure out where the error originates and ultimately the source of the issue. You should be able to get a rough idea from what happens in your code when the error occurs (are you creating a new connection, sending data, receiving data, etc...).
If that doesn't yield any obvious results I would probably create a test project using the yami source code instead of the library file so I would be able to trace into the yami code to where the error originates from.
This shouldn't be an unusual problem, but I cannot find anything about it at google or at other search machine.
So, I've made an application using C++ and QtCreator. I 've made a new mime type for application's project files.
My system (ubuntu 10.10), when I right click a file and I choose "Open With 'Default Application'" the it runs
Code:
default_application path/to/the/selected/file1
So, if you select multiple files and select "Open With 'Default Application'" the system will call
Code:
default_application path/to/the/selected/file1
default_application path/to/the/selected/file2
default_application path/to/the/selected/file3
So, this is a big problem for me, because I handle the concurrent processes from inside the program, so when another instance of the program is running, a warning message is appeared. So, each application's call will recognize the others as currently running applications and so it'll show the message. I'll end up with 3 Messages saying that another process of the program is running --_--'
My application handles multiple URLs this way:
Code:
myapp path/to/the/selected/file1 path/to/the/selected/file2 path/to/the/selected/file3
How can I make my code handle all these multiple instances at the same time? Everything I've tried fails, because everything I've tried requires a check from the first instance called, which is too slow and other instances come app and all together are warning about concurrent processes of the same program
So, how can I fix this? is it system depended, or can I do something with the code?
The way is to make your application recognize that there is already an instance running and make the new instance just forward a request to the first instance before dying :)
EDIT:
The way to do that is to have your first application instance behave as a server. The pseudo algo is something like :
start();
try_to_contact_master_server_instance();
if(no_master())
{
I_am_master();
start_listening_server_that_wait_for_requests();
}
else
{
send_request_to_master("open file path/to/the/selected/file1");
send_request_to_master("open file path/to/the/selected/file2");
send_request_to_master("open file path/to/the/selected/file3");
die();
}
handle_incoming_requests();
I hope it's clearer ? Tell me if you need more precisions ...
For the server part, you can do your own or use some software bus provided by the OS like dbus or whatever, but it makes your application dependent, of course.
my2c
I have a Delphi web server providing some web services*. One of them is supposed to generate and return a PDF report.
The PDF creation is done with a QReport that is then exported into a PDF file with the ExportToFilter procedure.
The routine works fine when called from within an application, but when called behind a TIdTCPServer, it hangs and never finishes. Debugging it, I got tho the hanging point:
(note: I'm home right now and I don't have the source code. I'll try to reproduce quickrpt.pas' source as accurrate as I can remember).
procedure TCustomReport.ExportToFilter(TQRDocumentFilter filter);
...
AProgress := TQRFormProgress.Create(Application); // Hangs on this line
AProgress.Owner := QReport;
if ShowProgress then AProgress.Show;
QReport.Client := AProgress;
...
Searching the web, I found in this page (1) the suggestion to set ShowProgress to False, and edit the code so that it does not create the progress form when ShowProgress is set to false (apparently, this is due to QReport not being threadsafe).
So, I edited the code, and now I have this:
procedure TCustomReport.ExportToFilter(TQRDocumentFilter filter);
...
if ShowProgress then
begin
AProgress := TQRFormProgress.Create(Application);
AProgress.Owner := QReport;
AProgress.Show;
QReport.Client := AProgress
end;
...
Now, the report comes out. But then the service gets to an Invalid Pointer Exception (which I can't trace). Following calls to the service complete successfully, but when I shut down the service** it starts whining again with Invalid Pointer Exceptions, then the "MyServer has commited an invalid action and must be closed" windows message, then again a couple of times more, then just the pointer exception, then comes to error 216 (which as far as I could find out, is related to Windows access permissions).
Thanks!
Update (jan 5): Thanks Scott W. for your answer. Indeed, after some research, I found another suggestion that only the main thread can access some components. So I set the QR code back to normal and called the main method from a Synchronize call inside a TThread (so that way the main thread would handle it). But I still get the same error.
You mention you were able to generate PDF as a service with QR 4. Maybe that's why it's not working for me, since I'm using QR 3. On the other hand, you don't mention if you're doing that behind a TIdTCPServer (which is my case, providing web services) or if you run it by itself (for instance, during a batch process).
Anybody knows whether my QR version might be the problem? Thanks!
* Running Delphi 7 and QuickReport 3 on a Windows XP SP2. The server is based on Indy.
** I have two versions of the server: a Windows application and a Windows Service. Both call the same inner logic, and the problem occurs with both versions.
Update (mar 8): After all, my problem was that my printing routine was in another dll, and the default memory management module is somewhat crappy. Setting the first uses of my .dpr to be ShareMem overrides the memory management module with Borland's implementation, and solved my problem.
uses
ShareMem, ...
(1): http://coding.derkeiler.com/Archive/Delphi/borland.public.delphi.thirdpartytools.general/2006-09/msg00013.html
I'm guessing that QReport.Client is used somewhere later in the code, and with your modified code no longer assigning it to AProgress, you end up with an error.
Are you sure that you have to modify the QuickReport source? I have used QuickReport in a Windows Service to generate a PDF file and then attach to email message and all worked fine without having to modify the QR source. I don't recall exactly which settings had to be made, but it was done with Delphi 6 and QR 4.06.