Question

I attach a debugger by passing ‘-d’ as a command line parameter to my console app. That causes the following code to be called;

bool attachedDebugger = false;
try
{
   attachedDebugger = System.Diagnostics.Debugger.Launch();
}
catch (Exception) { }
finally
{
   Console.WriteLine(attachedDebugger ? "Debugger Attached" : "Failed to attach debugger");
}

After the Visual Studio 2010 JIT window pops up I sometimes change my mind and don’t want to debug, so I dismiss the dialog. If I don’t attach one then the Application exits immediately without anything being written to the console.

I know that this it a bit of an edge use case, I should just remove the ‘-d’ from the command line if I don’t want to debug. The reason for my question is that I wish to understand what’s happening.

I thought the finally block is always called, furthermore I would expect my application to continue if we fail to attach a debugger.

• Why is nothing printed to the console
  if I decline attaching a debugger?
• Does Debugger.Launch() call
  System.Exit on failure to attach?

EDIT Thanks @Moo-Juice I now know that a return value of false implies a debugger was already attached but the questions above remain unresolved.

Answer 1

This is a reported bug in dotnet 4.0