Managed code

Managed code is a differentiation created by Microsoft to identify computer program code that requires and will only execute under the "management" of a Common Language Runtime virtual machine (resulting in Bytecode). This disambiguation is prevalent and relevant only when developing Microsoft OS applications that interact with the .NET Framework or other Common Language Runtime implementations, like Mono. In this same context programmers also refer to code that doesn't depend on the Common Language Runtime as unmanaged.

Program code in any programming language could, in principle, be compiled into either managed code, some of the already existing programming languages have already been ported into the Common Language Runtime, and new languages created only on that platform.

Microsoft's Visual C++ development environment can produce both managed code (running under the .NET Common Language Runtime) or compiled binaries, running directly on the Windows platform with the help of its C Runtime Library..

Benefits of using managed code include programmer convenience (by increasing the level of abstraction, creating smaller models) and enhanced security guarantees, depending on the platform (including the VM implementation). There are many historical examples of code running on a virtual machines, such as UCSD Pascal utilizing p-code. Java popularized this approach with its bytecode executed by the Java Virtual Machine.

This is not to be confused to how compilers produce intermediate "pseudocode" with intention of compiling it further into target machine code, not running it within a virtual machine as managed code (see, for example, BCPL or ALGOL 68C).

Another source of confusion was created when Microsoft started connecting the .NET Framework with C++, it decided to call the result Managed C++, after some criticism on that name choice and further integration, C++/CLI took over.

External links

• Channel9 video of the Microsoft Research OS made in fully managed C# code