The main software that we built is built using VB6 (old school, I know). We're having some problem for viewing a report using ActiveReports. We did many Debug DLLs and were unable to find why the problem happen. Note that restarting the server solves the issue, which brings us to think that the problem is resource related.
Is there a way I can see how much memory is being used by a DLL? I would like to see if an object in that dll might not be released correctly.
I tried using the performance monitor, but this is not as precise as needed.
Is there anything i could use to monitor a Dll's usage?
We are just doing it the hard way and monitoring a server running multiple instances of the DLL.
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We're porting an old Visual Studio 6 application to Windows 7. The application heavily uses COM and the old RogueWave database interface. We're having a very random sever crash which looks like some sort of memory integrity problem. The crash occurs in the COM application. The application is started using COM, after starting up it tries to connect to the database. One of the following will occur:
1) Sometimes the COM application will have a sever crash
2) Sometimes it will work
3) Sometimes it will not be able to connect to the database and never will even with retries.
4) Sometimes when calling the RogueWave database creation, it does not return.
When starting the COM application several times in a row it will display any number of these symptoms.
At this point I have not been able to identify what is causing the instability.
The application will also crash when started normally, not using COM, but crashes less frequently.
Previously I saw a problem with identical symptoms in another area of this product. I was able to identify that the symptoms were tied to calls into a dll which were returning a CString that was created as a local variable. The dll is built using _AFXDLL preprocessor definition. After removing the calls to this dll this problem no longer occurs. This problem was occurring in many places.
At first I thought that this problem was caused because the dll was not built as an AFX EXTENSION DLL, but after reading through the documentation the _AFXDLL preprocessor definition will also build the dll as an AFX_EXTENSION_DLL. I'm used to using the _AFXEXT preprocessor directive to build AFX_EXTENSION dlls.
The COM application that is now crashing does not use this DLL. There is another DLL used by the COM application that has 1 exported function that returns a CString created as a local variable. This exported function is not called during the database connection.
Anyone have any ideas what would be causing this apparent memory integrity crash in a COM application? Thank you in advance for your help.
This turned out to be caused by a bug in the Oracle 10g express client dll.
I'm currently trying to compile an old program (made with C++ builder 2 or 3) with the "current" Embarcadero RAD Studio XE2.
So, I was wondering whether there is an easy way to use the old code, as Borland once claimed to be fully compatible to lower versions... however I couldn't find a "project-file", only source-code (.cpp, .h, .res, etc.).
I tried to "add to project" the main .cpp, however there seem to be some wrong include-paths... it also seem to use the OWL-package and includes its important source-files...
I'm a bit confused which type of main project I have to open first, since you need to open a new project before adding the source to it. As the running .exe has a GUI, I tried a Form-Window first, but it may be better to use a console or service as the real form is produced within the code as far as I understand.
So, after installing OWL and correcting the include-paths, do you think it should be running fine? Or is there something else to take care of?
If your old project was using OWL, you're probably well outside of the supported upgrade path.
That being said, valid C++ code should still compile and work and I've heard of people using OWL with recent versions of C++Builder. (via OWLNext)
Regarding your confusion as to which type of project to use, I believe a console application would be your best bet. A forms application is completely wrong, that will bring in the VCL and give you no end of problems trying to reconcile the different windowing systems. A service application is a completely different beast as well, and isn't meant for GUI applications. A console application should work, but you'll need more. The OWLNext project has a wiki that should help quite a bit.
I have a interesting problem: Where I work we've built a home-grown ERP system in VB6 that we are slowly moving over into vb.net. There are some projects have are in .net: we have a hand-held C# project that uses a web service to talk to our database, I've built some reporting screens using Crystal and some smaller maintenance screens.
Well as we have been plotting the conversion out, we want to have a way to separate our business logic and UI so that the UI can be a win/web form or a Smart Device project. Is this even possible? I try to reference the DLL in a test I have and it gives me this error when trying to debug using a emulator
Deployment and/or registration failed with error: 0x8973190e. Error writing file '%csidl_program_files%\smartdeviceproject1\system.windows.forms.dll'. Error 0x80070070: There is not enough space on the disk.
I'm not sure what it's doing... I take my DLL out and it works fine. Does anyone know of a way I can create a DLL that can target all of these UI without may changes?
This post here
helped me alot. Using a linked projects with conditional complation would seem to work in my case.
I have a vb.net project which sometimes, when running in the IDE, suddenly hangs. Normally this wouldn't be a problem. Just hit 'pause', look at the currently running threads, and find the deadlock (or whatever else).
But now I'm running into a situation where not only does the program hang, but trying to pause it causes visual studio itself to hang. In order to get control back, I have to kill the program-being-debugged's process, at which point visual studio comes back to life and says it was unable to pause execution. This is frustrating, because killing the process means the program state is lost (of course), so I don't know where the hang is.
So are there any common causes for this behavior? What should I be looking for?
if your program installs global hooks (which communicate with app) - this might be the case. A hook tries to communicate with your app (which is paused by debugger) and gets locked. And debugger is unable to receive its window messages: classic deadlock between hooked debugger (with hook dll) and a hooking app.
Finding a specific fix for a Visual Studio problem can be tricky: http://social.msdn.microsoft.com/Search/en-US/?query=visual%20studio%202008%20hang&ac=3
Additionally, not all hotfixes from Microsoft get released directly to the public. Some are only given out to customers whose systems are exhibiting a specific problem. So you have to contact Microsoft to the get the fix. They do this to limit the potential downside of releasing a hotfix that may break something else. So if all else fails, give them a call.
Here are some other things that I like to do when Visual Studio starts acting up:
Delete old breakpoints and watch variables.
With visual studio not running, delete the intellisense file (.ncb)
Clean the solution and then do a rebuild of all of the code.
Check hotfixes and service packs. I've seen a bug related to .net programming and debugging hangs. (VS hangs for me when debugging C++ 32-bit apps on 64-bit os:es sometimes.)
I just had a very similiar issue (VS fails to break execution), using Debug -> Delete all breakpoints solved the issue.
I'd check the code of the program being debugged, I'm thinking there may be an infinite loop or race condition in the code you're trying to debug. This has been the case for me in the past, especially on a single-core laptop I used to have. Can you give any information about where in the program you think execution is when you try to pause?
We have 3 developers all using the same version (VS 2008 SP1) and we all use large VB projects (windows forms). From time to time, the IDE will have all sorts of issues such as locking up, crashing, and even not being able to drag a form object around or it will just instantly disappear.
On the largest of our projects (which is actually 5 projects in one solution file), a couple people here can only rebuild the project for testing 2 - 3 times before they have to close the studio and reopen it.
Has anyone else experienced this? Does this happen with large C# projects?
Yes, I experience this all the time! It has gotten better in 2008, if you can believe it.
I usually find that the reason has to do with an exception in my own code. The UI might bring in a custom control that does not behave well in design mode, causing the problem.
Sometimes, I will bring up a second execution of VS2008 and attach the debugger to the first execution of VS. Then, I can debug my own code as it is being run in the designer of the first instance. Often, an exception is thrown and I can fix my code to play better in the designer.
In other circumstances, I have no idea why it happens.
I have heard of people having this issue, however, I have never had an issue at all myself.
I have heard that a number of people trace the issues back to the use of ReSharper as the primary cause.
The most common problem I've had that causes the designer to crash is when I create a form where the only constructors require parameters.
To alleviate that, when I need the form only to be instantiated with parameters, I create a private parameterless constructor that the designer can use but which the form's consumers won't see.
I have personally experienced all sorts of designer wickedness with VS2008 sp1. I uninstalled the service pack to return stability to my dev environment. This is an unfortunate answer, but give it a try.
Only thing I've had close to this is the design view crashing and bringing up an error, formerly causing me to have to recreate the form and copy and paste the code across until I learnt how to fix it.
My problem was occurring because of me using ctrl+f a lot though. If you are using big files, this might be what's happening.