Displaying exception debug information to users

Question

I\'m currently working on adding exceptions and exception handling to my OSS application. Exceptions have been the general idea from the start, but I wanted to find a good e

Answer 1

No it's not stupid. It's a very good idea, and it costs virtually nothing at runtime until you hit an unhandled exception, of course.

Be aware that there is already an exception handler wrapping your thread, provided by the OS (and another one by the C-runtime I think). You may need to pass certain exceptions on to these handlers to get correct behavior. In some architectures, accessing mis-aligned data is handled by an exception handler. so you may want to special case EXCEPTION_DATATYPE_MISALIGNMENT and let it pass on to the higher level exception handler.

I include the registers, the app version and build number, the exception type and a stack dump in hex annotated with module names and offsets for hex values that could be addresses to code. Be sure to include the version number and build number/date of your exe.

You can also use VirtualQuery to turn stack values into "ModuleName+Offset" pretty easily. And that, combined with a .MAP file will often tell you exactly where you crashed.

I found that I could train beta testers to send my the text pretty easily, but in the early days what I got was a picture of the error dialog rather than the text. I think that's because a lot of users don't know you can right click on any Edit control to get a menu with "Select All" and "Copy". If I was going to do it again, I would add a button that copied that text to the clipboard so that it can easily be pasted into an email.

Even better if you want to go to the trouble of haveing a 'send error report' button, but just giving users a way to get the text into their own emails gets you most of the way there, and doesn't raise any red flags about "what information am I sharing with them?"