In Visual Basic I create an Application Object and start it:
gApp = New CANoe.Application
gMeasurement = gApp.Measurement
gApp.Open(arrArgs(0), False, False)
gMeasurement.Start()
Once the application finishes processing the data two possible scenarios may happen: (i) the data file was corrupt and (in normal circumstances) an allert window is raised and (ii) the data file was ok. In (ii) case I can quite the Application with gApp.Quit(). However in case (i) gApp.Quit() does not work, since the program expects input from the user (although often I do not see the window at all).
Question 1: how can I quite the process corresponding to gApp? Currently I am quiting this in this way:
For Each p As Process In Process.GetProcesses
If p.ProcessName = "CANoe32" Then
p.Kill()
End If
Next
In general this is a bad solution since more instances of CANoe32 may run (although in this particular case only one process of this binary may run on the system).
Question 2 what would be a more elegant solution to quit the gApp in case it has child windows?
Any comments are very helpful
A possible solution to the problem would to use something similar to this ticket:
how-do-i-get-the-process-id-from-a-created-excel-application-object
Related
I´ve got a Job that runs a TaskletStep, then a chunk-based step and then another TaskletStep.
In each of these steps, errors (in the form of Exceptions) can occur.
The chunk-based step looks like this:
stepBuilderFactory
.get("step2")
.chunk<SomeItem, SomeItem>(1)
.reader(flatFileItemReader)
.processor(itemProcessor)
.writer {}
.faultTolerant()
.skipPolicy { _ , _ -> true } // skip all Exceptions and continue
.taskExecutor(taskExecutor)
.throttleLimit(taskExecutor.corePoolSize)
.build()
The whole job definition:
jobBuilderFactory.get("job1")
.validator(validator())
.preventRestart()
.start(taskletStep1)
.next(step2)
.next(taskletStep2)
.build()
I expected that Spring Batch somehow picks up the Exceptions that occur along the way, so I can then create a Report including them after the Job has finished processing. Looking at the different contexts, there´s also fields that should contain failureExceptions. However, it seems there´s no such information (especially for the chunked step).
What would be a good approach if I need information about:
what Exceptions did occur in which Job execution
which Item was the one that triggered it
The JobExecution provides a method to get all failure exceptions that happened during the job. You can use that in a JobExecutionListener#afterJob(JobExecution jobExecution) to generate your report.
In regards to which items caused the issue, this will depend on where the exception happens (during the read, process or write operation). For this requirement, you can use one of the ItemReadListener, ItemProcessListener or ItemWriteListener to keep record of the those items (For example, by adding them to the job execution context to be able to get access to them in the JobExecutionListener#afterJob method for your report).
I have a SQLite database that I want to lock for synchronization purposes. I don't want a process that runs async on a different box processing data that has been added from a different box until it has finished with updates. DataAccess is a class that connects to sPackageFileName and reuses the same connection as long as sPackageFileName is the same or unless .Close method is called. So basically DataAccess.ExecCommand executes a command.
In Google I found this ....
DataAccess.ExecCommand("PRAGMA locking_mode = EXCLUSIVE", sPackageFileName)
DataAccess.ExecCommand("BEGIN EXCLUSIVE", sPackageFileName)
DataAccess.ExecCommand("COMMIT", sPackageFileName)
This works as advertise. If I run this on box A and then on box B I get a "database locked" exception. The problem is how long it takes. I found a PRAGMA busy_timeout. This PRAGMA is timeout controls access locks, not database locks. I am stratring to think there is not PRAGMA for database lock timeout. Right now it seems about 3-4 minutes. One other note, the sPackageFileName is not on either box, they (box A and B) connect to it over a share drive.
Also I am using the VB.NET wrapper for the SQLite dll.
CL got me on the right trail. It was the timeout of the .NET command. Here the code setting it up from my class.
Dim con As DbConnection = OpenDb(DatabaseName, StoreNumber, ShareExclusive, ExtType)
Dim cmd As DbCommand = con.CreateCommand()
If _QueryTimeOut > -1 Then cmd.CommandTimeout = _QueryTimeOut
Don't get hang up on the variables, the purpose of posting the code is show I could show the property I was talking about. The default _QueryTimeOut was set the 300 (seconds). I set cmd.ComandTimeout to 1 (second) and it returned as expected.
As CL finally got through to me, the timeout was happening someplace else. Sometimes it takes a kick to get you out of the box. :-)
Does Clarion 8 offer anything for exception handling? I know as of Clarion 5 there was no support for things like try / catch but that was released almost 10 years ago. I can't seem to find any info on how to recover from exceptions in C6 to C8 unless I was using Clarion# (aka Clarion.NET) which I'm not. If there's definitely nothing like try / catch, are there any tricks or hacks that can be used to not have a program crash when an exception is thrown even if it goes unhandled?
If it helps, I'm using version 8.0.0.8778.
EDIT 1:
Here is some sample code for a basic program that should supposedly illustrate the feature PROP:LastChanceHook, however, I can't get it to work. When I run this program, I see the first message "Start", but then nothing happens. I've tried returning 0 or 1 from Hook but that hasn't made a difference either. Every time I run this, I have to go onto the Task Manager and end the process for the program because it's not being killed.
PROGRAM
INCLUDE('CWEXCPT.INT'), ONCE
MAP
Hook(*ICWExceptionInfo), LONG
Test(LONG,LONG)
END
CODE
MESSAGE('[Sample] Start')
SYSTEM{PROP:LastChanceHook} = ADDRESS(Hook)
Test(10, 0) ! Intentionally causes an exception
MESSAGE('[Sample] After Test')
RETURN ! Tried removing this, no difference
Hook PROCEDURE(*ICWExceptionInfo info)
CODE
MESSAGE('[Sample] Start Hook')
IF info &= NULL THEN RETURN 0 END
Message('An exception!')
RETURN 1 ! 0 = don't kill, anything > 0 = tell RTL to kill the thread
Test PROCEDURE (LONG a, LONG b)
CODE
a %= b
Yes, take a look at prop:LastChanceHook in the help. It may provide enough function for your needs.
In other cases, the info at this link might also be useful:
http://clarionsharp.com/blog/tracking-down-those-pesky-gpfs/
In the next public build of C8 (it's presently Sept 27, 2012), the buttons on that exception display (shown at the link above) can be customized a bit.
ok here is my code :
For i = 0 To 10
Dim tTemp As Threading.Thread = New Threading.Thread(AddressOf dwnld)
tTemp.IsBackground = True
'tTemp.Start(geturl)
lThreads.Add(tTemp)
'MsgBox(lThreads.Item(i).ThreadState)
Next
I create a list of threads with 10 threads, assign them a function, properties and add them to the list.
'While ListBox2.Items.Count > 0
For i = 0 To lThreads.Count - 1
If (lThreads.Item(i).ThreadState = 12) Then
If (ListBox2.Items.Count > 0) Then
lThreads.Item(i).Start(geturl)
If (i = lThreads.Count - 1) Then
i = 0
End If
Else
Exit For
End If
'MsgBox(lThreads.Item(i).ThreadState)
ElseIf (lThreads.Item(i).ThreadState = 16) Then
lThreads.RemoveAt(i)
Dim tTemp As Threading.Thread = New Threading.Thread(AddressOf dwnld)
tTemp.IsBackground = True
lThreads.Add(tTemp)
If (i = lThreads.Count - 1) Then
i = 0
End If
End If
Next
What's happening is, i see the threads stop after the function dwnld is completed. So i first check for the state (12 means background and unstarted). On case 12 start the thread and in case 16 (stopped) remove that particular thread and add a different thread like i add 10 above.
Also there is a check when the i counter reaches last number, restart the whole loop by assigning i=0.
The program downloads some web pages, the url is passed from the listbox2. The geturl will pass the url and remove it from the list. So when the listbox is empty, exit the for loop.
But the above code is running for only 11 times and it does not restart. I tried using a lable and goto but it simple hangs.
Can anyone tell me what to do?
What i want is to maintain 10 threads to keep downloading the web pages and when the list is empty, exit the function.
Trying to manually manage your own custom pool of threads is probably the wrong approach here. Use ThreadPool.QueueUserWorkItem or preferrably the new Task class. The thread pooling is managed for you which greatly simplifies the code. Completely scrap this code and start over using one of the techniques I just mentioned. If you run into problems implementing either of these techniques then post a more specific question.
Micro-management of threads is, well, just a really bad idea. The moment I see anyone trying to maintain a list of threads that are continually created, terminated and destroyed I just know they are doomed. I have seen experienced professionals trying to do it - it's fun looking on, waiting for the inevitable spectacular failure after months of trying to fix the unfixable.
Thread pools are, typically, nothing of the sort. They are usually a pool of tasks - task class instances on a producer-consumer queue - that several threads feed off as and when they are free to do work. The work threads auto-manage themselves by getting new tasks themselves when they have finished with the old one - no need for any higher-level micro management.
Listen to #Brian - forget managing lists of threads, checking their state and all that gunge. It'll just make you ill. Go with ThreadPool.QUWI or Tasks.
I have erlang application. In this application i run process with spawn(?MODULE, my_foo, [my_param1, my_param2, my_param3]).
And my_foo:
my_foo(my_param1, my_param2, my_param3) ->
...
some code here
...
ok.
When i open etop i see that this my_foo/3 function status: proc_lib:sync_wait/2
Than i try to put exit(self(), normal) in the end of my function, but i see same behavior: proc_lib:sync_wait/2 in etop.
How can i kill or exit process correctly?
Thank you.
Note that exit(Pid, Reason) and exit(Reason) do NOT do the same thing if Pid is the process itself. exit/1 tells the current process to exit - from the inside if you like - while exit/2 sends an exit signal to the process, even if the process is itself. So when you do exit(self(), normal) you are actually sending the normal exit signal to yourself, which is ignored.
In this case putting the exit call at the end of the function should not make any difference as the process automatically dies (with reason normal) when the function with which it was started ends. It seems like the process is suspended somewhere before that.
proc_lib:sync_wait/2 is called inside proc_lib:start/start_link and sits and waits for the spawned process to do proc_lib:init_ack/1/2 to return the return value for start. It would appear that your process does not call init_ack.
Based on the limited information that you give in the question I would suspect that your process hasn't finished running yet.
Normally you don't need to add exit/2 to your process. It will exit automatically when the function has finished running.
You probably have a long running call in some code here that has not finished running. I recommend that you add logging information and see where you are stuck.