I can't help but notice awful threading designs manifested in some apps (which will remain nameless). Here are some random grievances I have with these apps: 1. Don't block the UI thread, especially not on file or network access . When you block the...

If you think context switching activities is cheap, then just try saying two sentences; and then try interleaving those two sentences. For example, I can say "I like kites" and "puppies are cute" in under 2 seconds. But to interleave them ("I puppies...

I have a grievance with some programs that host many separate instances (main windows) hosted by a single process. On the plus side , you can get some good perf wins from this. One process can host many windows. (I think of this as the evolution of MDI...

While managed assemblies may be very interesting from the loader and deployment perspective, they don't really have much interesting for debuggers. The debugger is far more concerned with modules: - the key debugging functionality is associated with modules...

Be careful of Image File Execution Options (IFEO) with managed debugging - it won't work like you expect. IFEO lets you set some registry goo such that when you launch a target app (specified by a registry key name), a debugger (specified by a string...

Here is a template for playing around with an extension for the MDbg sample (Mdbg is the managed debuggeer written in C#). It adds an "Addition" command to MDbg that adds two numbers. Not very exciting, but it shows the plumbing. You can download the...

In .Net 2.0, we wanted to focus managed Edit-And-Continue (EnC) resources on the core-scenarios so that we could make those as good as possible. One significant resource was testing: if you think about what it means to really test EnC, you can probably...

Sometimes we think we can make a decision, but it turns out the decision is already made for us by the consequence of earlier choices. Mathematics is filled with great examples. One of my favorites is: e πi = -1 (that's e^pi*i == -1). (See proof from...

I was wondering how well properties were integrated into C#. For example, C# lets you use += with the properties. It's easy enough to convert: MyProperty += 4 to MyProperty = MyProperty + 4 However, C# won't let you pass a property in as a ref parameter...

My TV-savvy friends tell me that there's some magic number of TV episodes that means you finally have enough unique episodes to viably show re-runs. I wonder what that number is for blogging? I bet that some of those high volume bloggers could probably...

ICorDebug has many different ways of saying "failure". The full list is everything that starts with "CORDBG_" in CorError.h. There are a lot of very specific HRs to describe specific scenarios. For example, CORDBG_E_IL_VAR_NOT_AVAILABLE will tell you...

Sometimes ICorDebug APIs will return CORDBG_E_OBJECT_NEUTERED. If you're using MDbg, COM-interop will convert this to throwing an exception. This means that the object is "logically dead". Since somebody is holding an outstanding reference to it, we...

You can discern a lot of information about an API from what appear to be subtle or irrelevant details For example, each ICorDebug object has a logical parent. (See here for a brief explanation of the different ICorDebug interfaces). Here's a chart...

I find people will often say something is impossible, when really they just aren't s mart enough to figure it out. Physicists (and the Discovery channel) love pointing this out about time-travel: No law of physics, except for perhaps the law about...

VS (and mdbg) expose the $exception pseudo-variable which shows you the most recent exception. (kudos to Shaykatc for mentioning this a year ago). Debugger authors can implement this with: HRESULT ICorDebugThread::GetCurrentException([out] ICorDebugValue...

Here's random information about ICorDebugThread that I hope eventually makes it into MSDN: 1. The managed CreateThread callback comes at the first bit of managed code that a thread runs. (I think this is a bad for these reasons , and instead it should...