DotGNU is a decommissioned part of the

GNU Project The GNU Project ( ) is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and Computer hardware, computing dev ...

that started in January 2001 and aimed to provide a

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

replacement for

Microsoft Microsoft Corporation is an American multinational corporation and technology company, technology conglomerate headquartered in Redmond, Washington. Founded in 1975, the company became influential in the History of personal computers#The ear ...

's .NET Framework. The DotGNU project was run by the

Free Software Foundation The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985. The organisation supports the free software movement, with the organization's preference for software being distributed ...

. Other goals of the project are better support for non-

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

platforms and support for more processors. The main goal of the DotGNU project code base was to provide a class library that is 100% Common Language Specification (CLS) compliant.

Main development projects

Portable.NET

DotGNU Portable.NET, an implementation of the ECMA-335

Common Language Infrastructure The Common Language Infrastructure (CLI) is an open specification and technical standard originally developed by Microsoft and standardized by International Organization for Standardization, ISO/International Electrotechnical Commission, IEC (ISO/ ...

(CLI), includes software to compile and run

Visual Basic .NET Visual Basic (VB), originally called Visual Basic .NET (VB.NET), is a multi-paradigm, object-oriented programming language developed by Microsoft and implemented on .NET, Mono, and the .NET Framework. Microsoft launched VB.NET in 2002 as the ...

, C#, and C applications that use the .NET base class libraries, XML, and

Windows Forms Windows Forms, also known as WinForms, is a free, open-source graphical user interface (GUI) class library for building Windows desktop applications, included as a part of Microsoft .NET, .NET Framework or Mono, providing a platform to write c ...

. Portable.NET claims to support various

instruction set architectures In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. A device or program that executes instructions described by that ISA, ...

including

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel, based on the 8086 microprocessor and its 8-bit-external-bus variant, the 8088. Th ...

, PPC, ARM, and SPARC.

DGEE

DotGNU Execution Environment (DGEE) is a web service server.

libJIT

libJIT is a

just-in-time compilation In computing, just-in-time (JIT) compilation (also dynamic translation or run-time compilations) is compilation (of computer code) during execution of a program (at run time) rather than before execution. This may consist of source code transl ...

library A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

for development of advanced just-in-time compilation in

virtual machine In computing, a virtual machine (VM) is the virtualization or emulator, emulation of a computer system. Virtual machines are based on computer architectures and provide the functionality of a physical computer. Their implementations may involve ...

implementations,

dynamic programming language A dynamic programming language is a type of programming language that allows various operations to be determined and executed at runtime. This is different from the compilation phase. Key decisions about variables, method calls, or data types are ...

s, and

scripting languages In computing, a script is a relatively short and simple set of instructions that typically automation, automate an otherwise manual process. The act of writing a script is called scripting. A scripting language or script language is a programming ...

. It implements an

intermediate representation An intermediate representation (IR) is the data structure or code used internally by a compiler or virtual machine to represent source code. An IR is designed to be conducive to further processing, such as optimization and translation. A "good" ...

based on

three-address code In computer science, three-address code (often abbreviated to TAC or 3AC) is an intermediate language, intermediate code used by optimizing compilers to aid in the implementation of code-improving transformations. Each TAC instruction has at most t ...

, in which variables are kept in

static single assignment form In compiler design, static single assignment form (often abbreviated as SSA form or simply SSA) is a type of intermediate representation (IR) where each variable is assigned exactly once. SSA is used in most high-quality optimizing compilers for ...

. libJIT has also seen some use in other open source projects, including

GNU Emacs GNU Emacs is a text editor and suite of free software tools. Its development began in 1984 by GNU Project founder Richard Stallman, based on the Emacs editor developed for Unix operating systems. GNU Emacs has been a central component of the GNU ...

, ILDJIT and HornetsEye.

Framework architecture

The Portable .NET class library seeks to provide facilities for application development. These are primarily written in C#, but because of the Common Language Specification they can be used by any .NET language. Like .NET, the class library is structured into Namespaces and Assemblies. It has additional top-level namespaces including Accessibility and DotGNU. In a typical operation, the Portable .NET compiler generates a Common Language Specification (CLS) image, as specified in chapter 6 of ECMA-335, and the Portable .NET runtime takes this image and runs it.

Free software

DotGNU points out that it is Free Software, and it sets out to ensure that all aspects of DotGNU minimize dependence on proprietary components, such as calls to Microsoft Windows' GUI code. DotGNU was one of the High Priority Free Software Projects from till .

DotGNU and Microsoft's patents

DotGNU's implementation of those components of the .NET stack not submitted to the ECMA for standardization has been the source of patent violation concerns for much of the life of the project. In particular, discussion has taken place about whether Microsoft could destroy the DotGNU project through patent suits. The base technologies submitted to the ECMA may be non-problematic. The concerns primarily relate to technologies developed by Microsoft on top of the .NET Framework, such as

ASP.NET ASP.NET is a server-side web-application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, applications and services. The name stands for Ac ...

, ADO.NET, and

(see Non standardized namespaces), i.e. parts composing DotGNU's Windows compatibility stack. These technologies are today not fully implemented in DotGNU and are not required for developing DotGNU-applications. In 2009, Microsoft released .NET Micro Framework under Apache License, Version 2.0, which includes a patent grant. However, the .NET Micro Framework is a reimplementation of the CLR and limited subset of the base class libraries meant for use on embedded devices. Additionally, the patent grant in the Apache License would have protected only contributors and users of the .NET Micro Framework—not users and developers of alternative implementations such as DotGNU or Mono. In 2014, Microsoft released Roslyn, the next generation official Microsoft C# compiler, under the Apache License. Later that year, Microsoft announced a "reboot" of the official .NET Framework. The framework would be based on .NET Core, including the official runtime and standard libraries released under the

MIT License The MIT License is a permissive software license originating at the Massachusetts Institute of Technology (MIT) in the late 1980s. As a permissive license, it puts very few restrictions on reuse and therefore has high license compatibility. Unl ...

and a patent grant explicitly protecting recipients from Microsoft-owned patents regarding .NET Core.

References

External links

Project homepageArticle '2001 – The Year When DotGNU Was Born'
{{DEFAULTSORT:Dotgnu .NET implementations Computing platforms GNU Project software