From Java To C# A Developers Guide

1.10 Porting .NET to other operating systems

One common question is whether it is possible to port .NET to other non-Windows operating systems. ^[48] In theory, it is possible to write a .NET CLR for, say, a Linux machine. ^[49] This .NET CLR understands and provides a runtime environment for IL codes, in very much the same way that a JVM can be written for each operating system.

^[48] There have been reports about Microsoft funding the development of .NET on non-Windows operating systems. Corel Corp (in which Microsoft has a US$135 million investment) will be building an implementation of .NET programming tools that allows developers to build XML web services based on .NET for FreeBSD. A project codenamed Rotor, which is currently running at Microsoft, is dedicated at porting .NET to a non-Windows platform.

^[49] Of course, Windows-specific codes such as reading or writing to the Windows registry will not be truly portable. Either some clever tweaking has to be done, or developers writing portable .NET codes must avoid such operating system-specific functionalities.

There are already projects under development to do just this, ^[50] but it is my belief that .NET will remain a Windows-dominant technology. The CLR just wasn't designed for operating system portability, unlike the JVM. While the JVM is centered around the idea of operating system portability, .NET is about multiple languages and a single-vendor solution.

^[50] Project Mono (www.go-mono.com) by Ximian(www.ximian.com) aims to create an open source implementation of the .NET development framework. Mono includes a C# compiler, a runtime for the CLI, and a set of class libraries.