Python -> c++ dll -> c# dll
I have a com interop c# dll that is loaded in a wrapper c++ dll throught the .tlb file generated in c# to be used in a python project. When I run in my computer it works fine but when I run in a computer that just got formated it gives:
WindowsError: exception code 0xe0434f4d
I have the redistribute c++ installed and the .net compact framework 3.5 on the formatted computer.
How can I see what is the correct exception on a computer that does not have visual studio installed? How can I debug all of this? I can't debug the dll's itself can I?
Note: in my computer all works well so maybe is some dll or file missing. I allready used Dependency Walker to see if there's some dll missing, and nop!
Download the Microsoft Debugging Tools for Windows.
It contains the WinDbg debugger, which can also be used for debugging.
Advantage of WinDbg over Visual Studio is that you have much more low-level commands to find problems.
Disadvantage of WinDbg is that it's not that user friendly (compared to Visual Studio).
You can use WinDbg or other good applications to attach to the process or even run the application in the debugger application.
Another really good software is OllyDbg.
Both of these will both allow you to set breakpoints on different locations in your application.
Related
I'm quite new to VS Code. I have been debugging DLLs for 3rd party applications earlier in Visual Studio but it seems all the tools available there are not available in VS Code.
What I have been doing in VS earlier is:
create, develop and build my DLL to the plugins folder of that 3rd application (with references to the 3rd party application's libraries)
add the 3rd party exe as another project and set it as startup project.
when starting debugging session, VS automatically launches/attaches to my dll, i.e. I can step through my code when I start the plugin inside the app.
I am able to successfully build the DLL in VS Code to the correct folder and it works (will show me the simple msgbox i am waiting for). However, when I try to debug it by attaching the debugger to the 3rd party app process, the debugger does not stop at the breakpoints. When I hover over the breakpoint during debugging (which is not red anymore during debug), I get the message "No symbols loaded for this document". I guess I'm doing something wrong. The .pdb for the DLL is in that plugins directory. Is this because the debugger does not find it? Honestly, I'm not very well in with the launch.json contents yet (no need to work with those in full VS). What is the best way (if any) to do this kind of debugging in VS Code? In case this is something that definitely can't be done in VS Code, please let me know, so I know I need to return back to full IDE.
It turned out I just had some issues in my launch.json. I am now able to step through my code and the UX is practically the same than that with full VS. Problem solved.
#vernou Thanks for the link anyway!
I have a runtime written in C++ (with Mono embedded) which calls functions in a dll written in C# using mono_jit_exec and mono_runtime_invoke. The glue code is generated with CppSharp - which I don't think is relevant here, but just to mention.
So far all good, I can communicate in both directions.
What I want now is to debug the C# code only, using Visual Studio (I'm using the version 2019 on macOS). So in my C# project, I went to Run Configuration and selected the Start external program option pointing to my C++ assembly. After that, I've set some breakpoints, but when I run the C# project in Debug mode, they're never triggered.
Why is not working - is there something else that needs to be done? Is it because Mono is involved?
Ok, so the answer is that is currently not supported.
A workaround would be to do remote debugging using a plugin for Visual Studio or Visual Studio Code, as Unity does.
One available extension is VS Code Mono Debug, which is based on the SDB: Mono Soft Debugger Client.
So i have one C# desktop application that references a C++ dll. This dll project was developped by other persons, it can't be compiled on visual studio, I use NMake with the parameter -DCMAKE_BUILB=Debug to generate the .dll & .PDB files. I copied the files on the C# project reference folder and enabled Debugging of Unmanaged Code in the project properties. So im actualy able to debug unmanaged code from the dll. My issue is that i can't inspect any of the object nor the variables im lokking in the unmanaged code side. The visual studio contextual inspector doen't show when I passe my mouse on the objects/variables & when trying to add a spy it's not better. I need to see the values of the objects/variables from the unmanaged code to make sure it doen't do anything wrong.
Note : a coworker of mine had already opened a thread here How add spy on Visual studio using unmanaged code
But sadly the thread was closed for lack of details, so I tried to add more details to describe the issue.
Pls don't close this one
Inspect unmanaged C++ objects/variables on Visual studio 2017
Suggestion
Update 1
Please make sure that you have installed the C++ development and C# development workload in VS Installer. That's all the premises.
1) when you reference the path of the dll, make sure that the pdb file already exists under the reference folder(the folder where you referenced the dll) and then use DLLImport node to import the c++ functions.
2) Tools-->Options-->Debugging-->General-->check the option Used Managed Compatibility Mode
3) Right-click on your C# project-->Properties---> Debugging-->check the option Enable native code debugging
Also, check Allow unsafe code option under Build.
4) also, if your c++ dll is built with x64 platform, you should also use x64 platform to debug your c# main project.
In addition, you can refer to this similar issue for more detailed info.
I am developing a .NET core (.NET Standard 1.6) application in VS2015. The application calls C++ code via P/Invoke. Now I need to step into the C/C++ code of my native dll project.
In regular .NET application, by enabling unmanaged code debugging in the property window of the application, we can step into the C/C++ code directly:
But I can't find such option on a .NET core project. And I know that I can attach the debugger to the application to debug native code only, but that's not suitable for my case.
Again, I want to debug from managed C# code into native C/C++ code.
Any ideas?
Maybe I should switch back to .NET Framework so I can debug the native code. It's really hard to debug by printf. :(
UPDATE
The mixed mode debugging, i.e. debugging from managed C# code into native C/C++ code, has been implemented. See Tutorial: Debug managed and native code in Visual Studio.
UPDATE
The feature may have already been implemented, see this.
Just as #cynic said, this is not yet supported now (2016-11-1).
That can be verified by following steps provided by cynic.
Put a pause in your program (e.g. a Console.ReadKey call).
Attaching to the dotnet.exe process selecting "Managed (CoreCLR)" and "Native" code types
You'll get a message box stating explicitly that "Interop debugging is not supported".
Here is a proper way to debug the native dll.
Right click on the solution, Add Existing Project
Open 'dotnet.exe'. This is normally installed to 'C:\Program Files\dotnet\dotnet.exe'.
You should now see another node in solution explorer for dotnet.exe. Right click it to bring up project properties:
Change the working directory to be what you want
Change the arguments to be the path to your built dll
Change the exe project to your startup project
RECOMENDED: Go to Tools->Options->Projects and Solutions->Build and Run, uncheck 'Only build startup projects and dependcies on Run'
I have an old DLL written in Visual Studio 6 which I am calling from C# written in Visual Studio 2010. The DLL is not working properly and I want to debug into it. How can I do this? I have the source code project but cannot see how I can step into it.
Note: When I say "doesn't work", the call to the DLL succeeds and it gets a little way through the code in the DLL before failing, but I want to track down exactly where.
The technique of debugging a DLL is described here on MSDN. You'll need to do this from Visual Studio 6 (i.e. the tool that developed the DLL) and so the terminology will have changed. But the principles remain the same.
Attaching VS6 debugger on the .NET process shall work, as long you have the PDB file with the corresponding binary and the sources. You can break only on DLL code, however.
Attaching another VS+ shall work if the flag "Allow unmanaged debugging" is checked, but there is a possibility that symbols are not loaded by the debugger. A recompilation of the DLL shall solve the last problem.
Open Visual C++ Dll project, set breakpoint where you need. In the Project properties, Debug, Executable for debug session, type .NET executable file which uses this Dll. Start debugging (Go). When VC++ function is called, debugger breaks. Using this way, you can debug only unmanaged VC++ code.
Another way is to start debugging from .NET client in mixed debugging mode. Add VC++ project to the solution and rebuild it to debug both managed and unmanaged code.