Mismanaged code

Managed code is all the rage. Once long ago we had either slow code that was interpreted during runtime or fast compiled code that was built into a binary which the processor could execute natively. Microsoft said fuck this shit and introduced a middle ground. Probably to combat their mess of an operating system. To be fair, Microsoft wasn't first, they were just the ones to come up with the name.

Managed code does compile, not into something that is understood by the hardware CPU, but by a virtual processor. This way the program can be made more secure and portable between different architectures among other things. Java and dotNet are the most common platforms for managed code.

One of the many many problems with Windows is the convoluted way it runs and separates the 32 and 64 bit environment. Adding a third architecture, code that compiles into something that is neither 32 nor 64 bit Intel instructions adds to the confusion.

I wrote earlier about how a 64 bit Windows is really two Windows in one, Windows On Windows. As you might remember in the unlikely case you read that post, 32 bit processes access the 32 bit operating system, and 64 bit processes access the 64 bit one.

So, which OS is accessed by a program written in managed code?

It depends.

Lets say you need to deploy a program that requires some third party database client for an ODBC connection. The supplier tells you it needs the 64 bit version, "or it wont work". You have the 32 bit one installed sitewide already and you know they don't play well together. You know this, because you are an ORACLE.

Luckily, the program you need to deploy is written in C#. If a dotNet program utilize the 32 or 64 bit environment is decided by the programmer at compile time by setting the target platform. If he does not, it compiles to AnyCPU which chooses the 64 bit platform if available.

With the Microsoft tool corflags this can be changed after the fact! Flags in the file header tells the runtime environment if 32 bit is preferred or required and voila the program works well with the already installed 32-bit ODBC, saving me a lot of future work and headaches.

Java programs can be launched with either a 32 or 64 bit javaw.exe. Most Java programs can be launched with a specific client, bundled with the program itself. This is useful since most Java versions are incompatible with anything. But that's a different blog post.

Right now I'm working on something that is going to bring a different kind of headache. Cheers!