+<a href="#basics">Basics</a><br>
+<a href="#ximian">The Ximian Role in the Mono project</a><br>
+<a href="#gnome">Mono and GNOME</a><br>
+<a href="#gui">Building GUI applications with Mono</a><br>
+<a href="#msft">Mono and Microsoft</a><br>
+<a href="#pnpproject">Mono and the Portable.NET Project</a><br>
+<a href="#webservices">Web Services</a><br>
+<a href="#devel">Development Tools and Issues</a><br>
+<a href="#java">Mono and Java</a><br>
+<a href="#extending">Extending Mono</a><br>
+<a href="#portability">Portability</a><br>
+<a href="#reuse">Reusing Existing Code</a><br>
+<a href="#gcc">Mono and GCC</a><br>
+<a href="#performance">Performance</a><br>
+<a href="#licensing">Licensing</a><br>
+<a href="#patents">Patents</a><br>
+<a href="#etc">Miscellaneous Questions</a><br>
+
+
+<a name="basics"></a>
** Basics
-Q: Is Mono the same as Microsoft's .NET initiative?
+Q: What is Mono exactly?
-A: It is not.
+A: The Mono Project is an open development initiative sponsored by
+ Ximian that is working to develop an open source, Linux-based
+ version of the Microsoft .NET development platform. Its objective
+ is to enable Linux developers to build and
+ deploy cross-platform .NET Applications. The project will
+ implement various technologies developed by Microsoft that have now
+ been submitted to the ECMA for standardization.
- .NET is a company-wide initiative at Microsoft that
- encompasses many different areas. The .NET development framework,
- Passport, Biztalk, new server products, and anything that is
- remotely connected to .NET gets the ".NET-stamping" treatment.
- Some components of Microsoft's .NET initiative have been announced
- and some others are in the works.
+Q: What is the difference between Mono and the .NET Initiative?
- Mono is a project to implement several technologies developed by
- Microsoft that have now been submitted to the ECMA Standards Body.
+A: The ".NET Initiative" is a somewhat nebulous company-wide effort by
+ Microsoft, one part of which is a cross-platform development
+ framework. Mono is an implementation of the development framework,
+ but not an implementation of anything else related to the .NET
+ Initiative, such as Passport, software-as-a-service, or
+ corporate rebranding.
Q: What technologies are included in Mono?
* A compiler for the C# language. In the future we
might work on other compilers that target the Common
Language Runtime.
-
- Windows has compilers that target the
- virtual machine from
- <a href="http://msdn.microsoft.com/net/thirdparty/default.asp#lang">a
- number of languages:</a> Managed C++, Java Script,
- Eiffel, Component Pascal, APL, Cobol, Oberon, Perl,
- Python, Scheme, Smalltalk, Standard ML, Haskell,
- Mercury and Oberon.
</ul>
+
+ Windows has compilers that target the virtual machine from <a
+ href="http://msdn.microsoft.com/net/thirdparty/default.asp#lang">a
+ number of languages:</a> Managed C++, Java Script, Eiffel,
+ Component Pascal, APL, Cobol, Oberon, Perl, Python, Scheme,
+ Smalltalk, Standard ML, Haskell, Mercury and Oberon.
+
The CLR and the Common Type System (CTS) enables applications and
- libraries to be written in a number of languages. Classes and
- methods created in one language can be used from a different
- language.
+ libraries to be written in a collection of different languages that
+ target the byte code
This means for example that if you define a class to do algebraic
manipulation in C#, that class can be reused from any other
A: Yes, we will be implementing the APIs of the .NET Framework SDK
class libraries.
-Q: What does Mono stand for?
+Q: Will you offer an ECMA-compliant set of class libraries?
-A: Mono is the word for `Monkey' in Spanish. We like monkeys.
+A: Eventually we will. Our current focus is on interoperating
+ with the Microsoft SDK, but we will also offer an ECMA compliant
+ set of libraries.
-Q: When will you ship it?
+Q: What does the name "Mono" mean?
-A: We do not know when the code will be shipped. The more
- contributions we get to the project, the sooner it will ship.
+A: Mono is the word for `monkey' in Spanish. We like monkeys.
- A rough estimate is that we might be able to run our C# compiler on
- Linux by the end of the year. That means running the Windows
- Executable generated by a Microsoft .NET compiler on the Linux
- platform.
+Q: Is Mono usable?
- We expect that doing GUI applications will require more work on the
- class libraries. That could take another six months.
+A: The JIT engine is usable on Intel x86 machines. An interpreter
+ can be used on other non-Intel x86 machines.
+
+ The class libraries are not yet mature enough to run real applications,
+ but if you are interested in trying out Mono, you can definetly start
+ testing things out as many programs run.
+
+ The C# compiler has made significant progress, it can even compile
+ itself now, but it can not yet be ran with our class libraries as
+ they are missing some features.
+
+Q: When will you ship it?
+
+A: It is premature to target a shipdate for the code, but we
+ anticipate that it will be available some time in the middle of
+ 2002.
Q: How can I contribute?
A: Check the <a href="contributing.html">contributing</a> section.
-Q: You guys should innovate instead of copying.
+Q: Aren't you just copying someone else's work?
+
+A: We are interested in providing the best tools for programmers to
+ develop applications for Free Operating Systems. We also want to help
+ provide the interoperability that will allow those systems to fit in
+ with other standards.
-A: In this particular case, we see a clear advantage in the platform
- and we are interested in using the features of the CLI on open source systems.
+ For more background, read the <a href="http://www.go-mono.com/rationale.html">Mono
+ Project white paper</a>.
+ the project.
- We have decided that we should spend our limited resources towards
- implementing an existing specification instead of designing and
- implementing our own.
- Designing and implementing our own would be possible, but it doesn't make
- sense to do that just because the specification comes from a
- proprietary vendor.
+<a name="ximian"></a>
-** Ximian
+** The Ximian Role in the Mono Project
Q: Why is Ximian working on .NET?
-A: We are interested in providing the best tools for programmers to
+A: Ximian is interested in providing the best tools for programmers to
develop applications for Free Operating Systems.
For more information, read the project <a
Q: Will Ximian be able to take on a project of this size?
-A: Ximian will not be able to taken on the whole project on its own.
- Mono will be a free software/open source community project, that is
- the only way we can hope to implement something of this size. You
- can <a href="contributing.html">contribute</a> to this effort.
+A: Of course not. Ximian a supporter of the Mono project, but the only way
+ to implement something of this size is for the entire free software
+ community to get involved. Visit the <a href="contributing.html">contributing</a>
+ page if you'd like to help out.
Q: What pieces will Ximian be working on?
-A: We will focus on building a development and execution
- environment.
+A: We will devote most of our resources to work on the pieces which are
+ on the critical path to release a development and execution
+ environment. Once the project is at a stage where it is useful in
+ the real world, it will achieve a critical mass of developers to
+ improve it further.
- The idea is to get Mono to a state of that would allow
- third parties to actually be able to use it real-world development.
+Q: Will Ximian offer Mono commercially?
-Q: Why does Ximian even care?
+A: When Mono is ready to be shipped Ximian will offer a commercial
+ support and services for Mono.
-A: We like the features that the CLI and its related technologies
- bring to the table. An exciting addition to the developer toolkit.
- The goal of Mono is to bring this technology to non-Windows
- platforms (although we hope Mono will also run on Windows, for
- debugging and comparative purposes).
+Q: Will you wait until Mono is finished?
+A: Mono will ship on various stages as they mature. Some people
+ require only a subset of the technologies, those will ship first.
-** Licensing
+ More advanced features will take more time to develop. A support
+ timeline will be available in June 2002.
-Q: Will I be able to write proprietary applications that run with
- Mono?
+<a name="gnome"></a>
+** Mono and GNOME
-A: Yes. The licensing scheme is planned to allow proprietary
- developers to write applications with Mono.
-
-Q: What license is Mono on?
+Q: How is Mono related to GNOME?
-A: The C# Compiler is released under the terms of the GPL. The class
- libraries will be under the LGPL or the GPL with a special
- exception. The runtime libraries are under the LGPL.
+A: In a number of ways. This project was born out of the need of
+ providing improved tools for the GNOME community, and will use
+ existing components that have been developed for GNOME when they
+ are available. For example, we plan to use Gtk+ and Libart to
+ implement Winforms and the Drawing2D API and are considering
+ GObject support.
- Since the LGPL is not suitable for embedded systems development, we
- are also licensing the libraries under the GPL with the following exception:
+Q: Has the GNOME Foundation or the GNOME team adopted Mono?
- If you link this library against your own program, then you do not
- need to release the source code for that program. However, any
- changes that you make to the library itself, or to any native
- methods upon which the library relies, must be re-distributed in
- accordance with the terms of the GPL.
+A: Mono is too new to be adopted by those groups. We hope that the
+ tools that we will provide will be adopted by free software
+ programmers including the GNOME Foundation members and the GNOME
+ project generally.
- This is similar in spirit to <a
- href="http://www.gnu.org/software/classpath/classpath.html">GNU
- Classpath.</a>
+Q: Should GNOME programmers switch over to Mono now?
-Q: But in Object Oriented Programming I need to subclass your library
- functions, does that mean that I am making modifications to your
- library and hence I would have to distribute my sources under the
- LGPL?
+A: It is still far to early for discussions of "switching over." No
+ pieces of Mono will be ready within the next six months, and a
+ complete implementation is roughly one year away.
-A: No. Object Oriented Programming in the class library is a well
- understood interface barrier, so you can actually develop
- proprietary applications with the Mono libraries.
+ We encourage GNOME developers to continue using the existing tools,
+ libraries and components. Improvements made to GNOME will have an
+ impact on Mono, as they would be the "backend" for various classes.
-Q: Will you accept code under the XXX License?
+Q: Will Mono include compatibility with Bonobo components? What is the
+ relationship between Mono and Bonobo?
-A: If the XXX License is compatible with the license we use in that
- specific piece of code, then yes. If you want to use the BSD license, make
- sure you use the BSD license without the advertisement clause (The
- `Ousterhout License').
+A: Yes, we will provide a set of classes for implementing and using
+ Bonobo components from within Mono. Mono should allow you to write
+ Bonobo components more easily, just like .NET on Windows allows you
+ to export .NET components to COM.
-** Mono and .NET
+Q: Does Mono depend on GNOME?
-Q: If applications use Mono, does that mean that I have to pay a service fee?
+A: No, Mono does not depend on GNOME. We use a few packages produced by
+ the GNOME team like the `glib' library.
-A: No. Mono is not related to Microsoft's initiative of
- software-as-a-service.
+Q: But will I be able to build GNOME applications?
-Q: If you implement .NET, will I depend on Microsoft Passport to run my software?
+A: Yes, we will enable people to write GNOME applications using Mono.
-A: No. The .NET Framework is a runtime infrastructure and collection
- of class libraries. Passport may be required to access certain web
- services written for that framework, but only if the programmer
- chooses Passport as the authentication mechanism.
+<a name="gui"></a>
+** GUI applications
-Q: Is .NET just a bunch of marketing slogans?
+Q: Will Mono enable GUI applications to be authored?
-A: Although the `.NET initiative' is still quite nebulous, The .NET Framework
- has been available for some time. Mono is not an implementation of the .NET
- initiative, just the development framework.
+A: Yes, you will be able to build GUI applications. Indeed, that is our
+ main focus. We will provide both the Windows.Forms API and the Gtk# API.
-Q: What is a 100% .NET application?
+Q: What is the difference between Gtk# and System.Windows.Forms?
-A: A `100% .NET application' is one that only uses the APIs defined
- under the System namespace and does not use PInvoke. These
- applications would in theory run unmodified on Windows, Linux,
- HP-UX, Solaris, MacOS X and others.
+A: Gtk# is a set of bindings for the Gtk+ toolkit for C# (and other
+ CIL-enabled languages). System.Windows.Forms is an API defined
+ by Microsoft to build GUI applications.
-Q: But Microsoft will release a port of the real thing under the
- `Shared Source' license, why bother with anything else?
+Q: Will I be able to run my smart clients on systems powered by Mono?
-A: The Shared Source implementation will not be usable for commercial
- purposes. We are working towards an implementation that will grant
- a number of rights to recipients: use for any purpose,
- redistribution, modification, and redistribution of modifications.
+A: As long as your applications are 100% .NET and do not make use
+ of P/Invoke to call Win32 functions, your smart client applications
+ will run on Mono platforms.
- This is what we call <a
- href="http://www.gnu.org/philosophy/free-sw.html">Free Software</a>
+<a name="msft"></a>
+** Mono and Microsoft
-** Passport
+Q: Is Microsoft helping Ximian with this project?
-Q: Is this a free implementation of Passport?
+A: No. Ximian CTO Miguel de Icaza had a friendly conversation with
+ Microsoft software architect David Stutz, but that's about the
+ extent of the contact. Microsoft is interested in other
+ implementations of .NET and are willing to help make the ECMA spec
+ more accurate for this purpose.
-A: No. Passport is part of Microsoft's Hailstorm initiative. Mono
- is just a runtime, a compiler and a set of class libraries.
+ Ximian representatives have also spoken with Sam Ruby at the ECMA
+ TG3 committee to discuss the same issues.
-Q: Will the System.Web.Security.PassportIdentity class, mean
- that my software will depend on Passport?
-
-A: No. That just means that applications might use that API to
- contact a Passport site.
+Q: Is Microsoft or Corel paying Ximian to do this?
- As long as your application does not use Passport, you will not
- need Passport.
+A: No.
- It might even be possible to implement that class with
- a set of dummy functions, or use an alternate Passport implementation.
+Q: Do you fear that Microsoft will change the spec and render Mono
+ useless?
- We do not know at this time whether the Passport protocol is
- documented and whether we will be able to talk to
- passport.com
+A: No. Microsoft proved with the CLI and the C# language that it was
+ possible to create a powerful foundation for many languages to
+ interoperate. We will always have that.
-Q: What is your opinion?
+ Even if changes happened in the platform which were undocumented,
+ the existing platform would a value on its own.
-A: You can read my personal <a href="passport.html">opinion on
- passport</a>.
+Q: Are you writing Mono from the ECMA specs?
-Q: Will Mono running on Linux make Passport available for Linux?
+A: Yes, we are writing them from the ECMA specs and the published
+ materials in print about .NET.
-A: The Passport toolkit for Linux-based web servers is available from
- Microsoft.
+Q: If my applications use Mono, will I have to pay a service fee?
- Again, Mono has nothing to do with Passport.
+A: No. Mono is not related to Microsoft's initiative of
+ software-as-a-service.
-** Mono and Windows
+Q: Is the Mono Project is related to the Microsoft Hailstorm effort? Is
+ Ximian endorsing Hailstorm?
-Q: Will Mono allow me to run Microsoft Office on Linux?
+A: No. The Mono Project is focused on providing a compatible set of
+ tools for the Microsoft .NET development platform. It does not
+ address, require, or otherwise endorse the MS Passport-based
+ Hailstorm single sign-on system that is part of Windows XP and
+ other services.
-A: No, it will not. Microsoft Office is a Windows application. To
- run Windows applications on Intel Unix systems refer to <a
- href="http://www.winehq.com">the Wine Project</a>
+Q: Will Mono or .NET applications depend on Microsoft Passport?
-** GNOME
+A: No. MS Passport is unrelated to running .NET compatible applications
+ produced with the Mono tools. The only thing you will need is a
+ just-in-time compiler (JIT).
-Q: How is this related to GNOME?
+Q: What is a 100% .NET application?
-A: In a number of ways:
+A: A `100% .NET application' is one that only uses the APIs defined
+ under the System namespace and does not use PInvoke. These
+ applications would in theory run unmodified on Windows, Linux,
+ HP-UX, Solaris, MacOS X and others.
- * Mono will use existing
- components that have been developed for GNOME when it makes
- sense. For example on X systems, we will use Gtk+ and
- Libart to implement Winforms and the Drawing2D API.
+Q: If Microsoft will release a port of their .NET platform under the
+ `Shared Source' license, why should I bother with anything else?
- For database access, we will use LibGDA (not really
- depending on GNOME, but related to).
+A: The Shared Source implementation will be expensive and its uses
+ will be tightly restricted, especially for commercial use. We are
+ working towards an implementation that will grant a number of
+ important rights to recipients: use for any purpose,
+ redistribution, modification, and redistribution of modifications.
- * This project was born out of the need of providing improved
- tools for the GNOME community.
+ This is what we call <a
+ href="http://www.gnu.org/philosophy/free-sw.html">Free Software</a>
- * We would like to add support to our CLR implementation to
- deal with GObjects (in GNOME 1.x, they are called
- GtkObjects), and allow Mono developers to provide GObjects
- or use and extend existing GObjects.
+Q: Is Mono a free implementation of Passport?
-Q: Has the GNOME Foundation or the GNOME team adopted Mono?
+A: No. Mono is just a runtime, a compiler and a set of class
+ libraries.
-A: Mono is too new to be adopted by those groups. We hope that the
- tools that we will provide will be adopted by free software
- programmers including the GNOME Foundation members and the GNOME
- project generally.
+Q: Will the System.Web.Security.PassportIdentity class mean
+ that my software will depend on Passport?
+
+A: No. Applications may use that API to contact a Passport site, but
+ are not required to do so.
-Q: Should GNOME programmers switch over to Mono?
+ As long as your application does not use Passport, you will not
+ need Passport.
-A: Mono will not be ready even within the next six months, and a
- complete implementation is probably one year away.
+Q: Will Mono running on Linux make Passport available for Linux?
- We encourage GNOME developers to continue using the existing tools,
- libraries and components. Improvements made to GNOME will have an
- impact on Mono, as they will provide the "backend" for various
- classes.
+A: No. However, the Passport toolkit for Linux-based web servers is
+ available from Microsoft.
-Q: Will Mono include compatibility with Bonobo components?
+Q: Will Mono allow me to run Microsoft Office on Linux?
-A: Yes, we will provide a set of classes for implementing and using
- Bonobo components from within Mono.
+A: No, it will not. Microsoft Office is a Windows application. To
+ learn more about running Windows applications on Intel Unix systems
+ refer to <a href="http://www.winehq.com">the Wine Project</a>.
-** Mono and the Web
+<a name="pnpproject"></a>
+** Mono and Portable.NET
-Q: Is Mono a way of running Java applets?
+Q: What are the differences between Mono and Portable.NET?
-A: No.
+A: Most of Mono is being written using C#, with only
+ a few parts written in C (The JIT engine, the runtime, the
+ interfaces to the garbage collection system). The Portable.NET
+ Project is using C for development.
+<a name="webservices"></a>
** Web Services
-Q: Is Mono just a new way of writing Web Services?
+Q: How is Mono related to Web Services?
-A: No.
+A: Mono is only related to Web Services in that it will implement the
+ same set of classes that have been authored in the .NET Framework
+ to simplify and streamline the process of building Web Services.
-Q: If this implements the SDK classes, will I be able to write and
- execute .NET Web Services with this?
-
-A: Yes, you will.
+ But most importantly, Mono is an Open Source implementation of the
+ .NET Framework.
- When the project is finished, you will be able to use the same
- technologies that are available through the .NET Framework SDK on
- Windows to write Web Services.
+Q: Can I author Web Services with Mono?
-Q: What about Soup?
+A: You will be able to write Web Services on .NET that run on Mono and
+ viceversa.
-A: Soup is a library for GNOME applications to create SOAP server and
- SOAP clients. You can browse the source code for soup using <a
- href="http://cvs.gnome.org/bonsai">GNOME's Bonsai</a>
+Q: If Mono implements the SDK classes, will I be able to write and
+ execute .NET Web Services with it?
+
+A: Yes. When the project is finished, you will be able to use the
+ same technologies that are available through the .NET Framework SDK
+ on Windows to write Web Services.
+
+Q: What about Soup? Can I use Soup without Mono?
+
+A: Soup is a library for GNOME applications to create SOAP servers and
+ SOAP clients, and can be used without Mono. You can browse the
+ source code for soup using <a
+ href="http://cvs.gnome.org/bonsai">GNOME's Bonsai</a>.
Q: Can I use CORBA?
A: Yes, although the serializing tools have not yet been planned, and
you would probably have to implement them yourself.
-** Development Tools
+Q: Will Mono use ORBit?
+
+A: No. Mono will be using a new implementation of CORBA that isn't still started.
+
+<a name="devel"></a>
+** Development Tools and Issues
Q: Will it be possible to use the CLI features without using bytecodes
or the JIT?
Q: Will you have new development tools?
-A: Hopefully Free Software enthusiasts will contribute tools to
+A: With any luck, Free Software enthusiasts will contribute tools to
improve the developer environment. These tools could be developed
- initially using Microsoft implementation of the CLI and then
+ initially using the Microsoft implementation of the CLI and then
executed later with Mono.
+Q: What kind of rules make the Common Intermediate Language useful for
+ JITers?
+
+A: The main rule is that the stack in the CLI is not a general purpose
+ stack. You are not allowed to use it for other purposes than
+ computing values and passing arguments to functions or return
+ values.
+
+ At any given call or return instruction, the types on the stack
+ have to be the same independently of the flow of execution of your
+ code.
+
+Q: Is it true that the CIL is ideal for JITing and not efficient for
+ interpreters?
+
+A: The CIL is better suited to be JITed than JVM byte codes, but you
+ can interpret them as trivially as you can interpret JVM byte
+ codes.
+
+<a name="java">
** Mono and Java
-Q: What about using Java? After all there are many languages that
+Q: Why don't you use Java? After all, there are many languages that
target the Java VM.
A: You can get very good tools for doing Java development on free
wide variety of programming languages, and has a set of rules
designed to be optimal for JITers.
+Q: Could Java target the CLI?
-Q: What kind of rules make the Common Intermediate Language useful for
- JITers?
+A: Yes, Java could target the CLI. We have details on a <a
+ href="ideas.html#guavac">project</a> that someone could take on to
+ make this happen.
-A: The main rule is that the stack in the CLI is not a general purpose
- stack. You are not allowed to use it for other purposes than
- computing values and passing arguments to functions or return
- values.
+ Microsoft has an implemenation of the Java language called J# that
+ can target the CIL execution engine.
- At any given call or return instruction, the types on the stack
- have to be the same independently of the flow of execution of your
- code.
+Q: Is it possible to write a JVM byte code to CIL convertor?
-Q: I heard that the CIL is ideal for JITing and not efficient for
- interpreters, is this the case?
+A: Yes, it is possible. Here are a few starting point:
-A: The CIL is better suited to be JITed than JVM byte codes, but you
- can interpret them as trivially as you can interpret JVM byte
- codes.
+ <ul>
+ * A byte code representation is really a flattened forest of
+ trees. Look at the Mono JIT engine to see how we compute
+ the basic blocks (this is used to figure out the "trees").
-Q: Could Java target the CLI?
+ The forest is just an array of trees.
-A: Yes, Java could target the CLI. We have details on a <a
- href="ideas.html#guavac">project</a> that someone could take on to
- make this happen.
+ Indeed, run the JIT engine with -d (mono -d prog.exe) and
+ you will see how these trees look like.
+
+ You will have to do something similar for Java.
+
+ * Each "forest of trees" has a meaning. This meaning can now
+ be translated into the equivalent "meaning" in CLR-land.
+ </ul>
+<a name="extending"></a>
** Extending Mono
Q: Would you allow other classes other than those in the
For more information on extending Mono, see our <a
href="ideas.html">ideas</a> page.
-** Mono and portability
+Q: Do you plan to Embrace and Extend .NET?
+
+A: Embracing a good technology is good. Extending technologies in
+ incompatible ways is bad for the users, so we do not plan on
+ extending the technologies.
+
+ If you have innovative ideas, and want to create new classes, we
+ encourage you to make those classes operate correctly well in both
+ Mono and .NET
+
+<a name="portability"></a>
+** Portability
Q: Will Mono only work on Linux?
applications with Mono, but if you are interested in providing a
port of the Winform classes to other platforms (frame buffer or
MacOS X for example), we would gladly integrate them, as long
- they are under a Free Software License.
+ they are under an open source license.
+
+Q: Will Mono run on Windows?
-** Reusing existing Code
+A: We hope so. Currently some parts of Mono only run on Windows
+ (the C# compiler is a .NET executable) and other parts have only
+ been compiled on Linux, but work on Windows with Cygwin.
+
+Q: Will Mono depend on GNOME?
+
+A: It will depend only if you are using a particular assembly (for
+ example, for doing GUI applications). If you are just interested
+ in Mono for implementing a `Hello World Enterprise P2P Web
+ Service', you will not need any GNOME components.
+
+<a name="reuse"></a>
+** Reusing Existing Code
Q: What projects will you reuse or build upon?
Q: What about Intel's research JIT framework, ORP?
A: At this time, we are investigating whether we can use elements of
- ORP for Mono. ORP is a research JIT engine that has a clear
+ ORP for Mono. ORP is a research JIT engine that has a clearly
defined API that splits the JIT from the GC system and the actual
- byte code implementation. It is a research product.
+ byte code implementation.
Q: What about using GNU Lightning?
href="http://www.gnu.org/software/lightning/lightning.html">GNU
Lightning</a>.
-<a name="ximian-and-microsoft">
-** Ximian and Microsoft
-
-Q: I read that Microsoft is helping out Ximian, is this true?
-
-A: Initial contact between David Stutz and Miguel de Icaza happened.
- It was a friendly conversation. Microsoft is interested in other
- implementing .NET and are willing to help make the ECMA spec more
- accurate for this purpose.
-
- We were initially contacted by Sam Ruby at the ECMA TG3 committee
- to discuss the same issue. And we are glad to have good contacts
- to ask questions about the specs.
-
-Q: Do you fear that Microsoft will change the spec and render Mono useless?
-
-A: No. Microsoft proved with the CLI and the C# language that it was
- possible to create a powerful foundation for many languages to
- interoperate. We will always have that.
-
- Even if changes happened in the platform which were undocumented
- (which is very unlikely), the existing platform has a value on its
- own.
-
- Miguel once explained its motivation for working on Mono to Dave
- Winer, and his mail got posted <a
- href="http://scriptingnews.userland.com/stories/storyReader$1275">here</a>
-
-Q: Didn't Miguel de Icaza say that `Unix Sucks'?
-
-A: Yes, he did, as a catch phrase in his opening remark on the Ottawa
- Linux Symposium. His talk focused on various ways to improve Unix.
-
- There is a paper describing some ways to improve Unix at:
-
- <a href="http://primates.ximian.com/~miguel/bongo-bong.html">
- http://primates.ximian.com/~miguel/bongo-bong.html</a>
-
-Q: Didn't Ximian's Miguel work for Microsoft?
-
-A: Actually, Nat Friedman (Ximian's co-founder) did work as an
- intern for Microsoft for one summer but Miguel did not.
-
-Q: Did Nat and Miguel meet at Microsoft?
-
-A: They met online on the Linux IRC network; They met in person for
- the first time in 1997.
-
-** Mono and Microsoft
-
-Q: How can you expect Mono to compete with Microsoft, wont this
- require an effort too large?
-
-A: You are right. Mono will never become a reality without the help
- of other contributors. Ximian is a small company that can not
- finish Mono alone. We will be working with members of the
- community to deliver the product.
-
-Q: Is Microsoft and Corel involved in the Mono implementation?
-
-A: No, they are not.
-
-Q: Are you writing Mono from the ECMA specs?
-
-A: yes, we are writing them from the ECMA specs and the published
- materials in print about .NET
-
-** Acronyms
-
-Q: What is the difference between CLR (Common Language Runtime) and
- CLI (Common Language Infrastructure)?
-
-A: CLI is the specification of an execution system. The Microsoft
- implementation of this specification is named CLR.
-
- Unless we come up with our own acronym, we could just call ours
- also CLR, just because it would do exactly the same thing the
- Microsoft implementation does.
-
-<a name="gcc">
+<a name="gcc"></a>
** Mono and GCC
-Q: Should someone work on a GCC front-end to C#?
-
-A: I would love if someone does, and we would love to help anyone that
- takes on that task, but we do not have the time or expertise to
- build a C# compiler with the GCC engine. I find it a lot more fun
- personally to work on C# on a C# compiler, which has an intrinsic
- beauty.
-
-Q: Should someone make a GCC backend that will generate CIL images?
-
-A: I would love to see a backend to GCC that generates CIL images. It
- would provide a ton of free compilers that would generate CIL
- code. This is something that people would want to look into
- anyways for Windows interoperation in the future.
+Q: Are you working on a GCC front-end to C#? A GCC backend that will
+ generate CIL images? What about making a front-end to GCC that
+ takes CIL images and generates native code?
-Q: What about making a front-end to GCC that takes CIL images and
- generates native code?
-
-A: I would love to see this, specially since GCC supports this same
- feature for Java Byte Codes. You could use the metadata library
- from Mono to read the byte codes (ie, this would be your
- "front-end") and generate the trees that get passed to the
- optimizer.
-
- Ideally our implementation of the CLI will be available as a shared
- library that could be linked with your application as its runtime
- support.
+A: We are currently seeking volunteers for those projects.
+ Visit the <a href="contributing.html">contributing</a> section if
+ you are interested.
Q: But would this work around the GPL in the GCC compiler and allow
people to work on non-free front-ends?
Q: Why are you writing a JIT engine instead of a front-end to GCC?
-A: The JIT engine and runtime engine will be able to execute CIL
- executables generated on Windows.
-
-** Mono and Portability
-
-Q: Will Mono work on other variants of Unix?
-
-A: Yes. We do not expect to add any gratuitous incompatibilities.
-
-Q: Will Mono run on Windows?
-
-A: Hopefully yes. Currently some parts of Mono only run on Windows
- (the C# compiler is a .NET executable) and other parts have only
- been compiled on Linux, but work on Windows with Cygwin.
-
-Q: Will Mono depend on GNOME?
-
-A: It will depend only if you are using a particular assembly (for
- example, for doing GUI applications). If you are just interested
- in Mono for implementing a `Hello World Enterprise P2P Web
- Service', you will not need any GNOME component.
+A: We want the JIT engine and runtime engine because they will be able
+ to execute CIL executables generated on Windows, and so no recompilation
+ will be necessary.
+<a name="performance"></a>
** Performance
-Q: How fast will be Mono?
+Q: How fast will Mono be?
A: We can not predict the future, but a conservative estimate is that
it would be at least `as fast as other JIT engines'.
- Now, wishfully thinking I hope that we will ship various JITs with
- Mono just like Microsoft has done. A fast JITer when maximum
- performance is not needed, but fast load times are important; And
- an optimizing JITer that would be slower at generating code but
- produce more optimal output.
+ We would like to ship various JIT engines with Mono, just like
+ Microsoft has done with their .NET development platform. We could
+ provide a faster, JIT for fast load times but lower performance,
+ and an and an optimizing JIT that would be slower at generating
+ code but produce more optimal output.
The CIL has some advantages over the Java byte code: it is really
an intermediate representation and there are a number of
restrictions on how you can emit CIL code that simplify creating
better JIT engines.
- For example, on the CIL the stack is not really an abstraction
- available for the code generator to use at will: it is just a way
- of creating a postfix representation of the parsed tree. At any
- given call point or return point, the contents of the stack are
+ For example, on the CIL, the stack is not really an abstraction
+ available for the code generator to use at will. Rather, it is a
+ way of creating a postfix representation of the parsed tree. At
+ any given call point or return point, the contents of the stack are
expected to contain the same object types independently of how the
- instructions was reached.
+ instruction was reached.
+
+<a name="licensing"></a>
+** Licensing
-** Assorted questions
+Q: Will I be able to write proprietary applications that run with
+ Mono?
+
+A: Yes. The licensing scheme is planned to allow proprietary
+ developers to write applications with Mono.
+
+Q: What license or licenses are you using for the Mono Project?
+
+A: The C# Compiler is released under the terms of the <a
+ href="http://www.opensource.org/licenses/gpl-license.html">GNU GPL</a>. The runtime
+ libraries are under the <a
+ href="http://www.opensource.org/licenses/lgpl-license.html">GNU
+ Library GPL</a>. And the class libraries are released
+ under the terms of the <a
+ href="http://www.opensource.org/licenses/mit-license.html">MIT X11</a>
+ license.
+
+Q: I would like to contribute code to Mono under a particular
+ license. What licenses will you accept?
+
+A: We will have to evaluate the licenses for compatibility first,
+ but as a general rule, we will accept the code under the same
+ terms of the "container" module.
+
+<a name="patents></a>
+** Patents
+
+Q: Could patents be used to completely disable Mono (either submarine
+ patents filed now, or changes made by Microsoft specifically to
+ create patent problems)?
+
+A: No. First, its basic functional capabilities have pre-existed too
+ long to be held up by patents. The basic components of Mono are
+ technologically equivalent to Sun's Java technology, which has been
+ around for years. Mono will also implement multi-language and
+ multi-architecture support, but there are previous technologies
+ such as UCSD p-code and ANDF that also support multiple languages
+ using a common intermediate language. The libraries are similar
+ to other language's libraries, so again, they're too similar to
+ be patentable in large measure.
+
+ However, if Microsoft does patent some technology, then our plan is
+ to either (1) work around it, (2) chop out patented pieces, (3)
+ find prior art that would render the patent useless.
+
+ Not providing a patented capability would weaken the
+ interoperability, but it would still provide the free software /
+ open source software community with good development tools, which
+ is the primary reason for developing Mono.
+
+<a name="etc"></a> **
+Miscellaneous Questions
Q: You say that the CLI allows multiple languages to execute on the
same environment. Isn't this the purpose of CORBA?
space. This means much less copying and no need for reference
counting.
+Q: Will you support COM?
+
+A: The runtime will support XPCOM on Unix systems and COM on Windows.
+ Most of the code for dynamic trampolines exists already.
+
+Q: Will Ximian offer certifications on Mono or related technologies?.
+
+A: It's possible. But there is no plan about this. So the short answer is no.
+