1 <a href="#basics">Basics</a><br>
2 <a href="#ximian">The Ximian Role in the Mono project</a><br>
3 <a href="#gnome">Mono and GNOME</a><br>
4 <a href="#gui">Building GUI applications with Mono</a><br>
5 <a href="#msft">Mono and Microsoft</a><br>
6 <a href="#pnpproject">Mono and the Portable.NET Project</a><br>
7 <a href="#webservices">Web Services</a><br>
8 <a href="#asp">Mono and ASP.NET</a><br>
9 <a href="#devel">Development Tools and Issues</a><br>
10 <a href="#java">Mono and Java</a><br>
11 <a href="#extending">Extending Mono</a><br>
12 <a href="#portability">Portability</a><br>
13 <a href="#reuse">Reusing Existing Code</a><br>
14 <a href="#gcc">Mono and GCC</a><br>
15 <a href="#performance">Performance</a><br>
16 <a href="#licensing">Licensing</a><br>
17 <a href="#patents">Patents</a><br>
18 <a href="#etc">Miscellaneous Questions</a><br>
24 Q: What is Mono exactly?
26 A: The Mono Project is an open development initiative sponsored by
27 Ximian that is working to develop an open source, Unix
28 version of the Microsoft .NET development platform. Its objective
29 is to enable Unix developers to build and
30 deploy cross-platform .NET Applications. The project will
31 implement various technologies developed by Microsoft that have now
32 been submitted to the ECMA for standardization.
34 Q: What is the difference between Mono and the .NET Initiative?
36 A: The ".NET Initiative" is a somewhat nebulous company-wide effort by
37 Microsoft, one part of which is a cross-platform development
38 framework. Mono is an implementation of the development framework,
39 but not an implementation of anything else related to the .NET
40 Initiative, such as Passport, software-as-a-service, or
43 Q: What technologies are included in Mono?
45 A: Mono contains a number of components useful for building new
49 * A Common Language Infrastructure (CLI) virtual
50 machine that contains a class loader, Just-in-time
51 compiler, and a garbage collecting runtime.
53 * A class library that can work with any language
54 which works on the CLR.
56 * A compiler for the C# language. In the future we
57 might work on other compilers that target the Common
62 Windows has compilers that target the virtual machine from <a
63 href="http://msdn.microsoft.com/net/thirdparty/default.asp#lang">a
64 number of languages:</a> Managed C++, Java Script, Eiffel,
65 Component Pascal, APL, Cobol, Oberon, Perl, Python, Scheme,
66 Smalltalk, Standard ML, Haskell, Mercury and Oberon.
68 The CLR and the Common Type System (CTS) enables applications and
69 libraries to be written in a collection of different languages that
72 This means for example that if you define a class to do algebraic
73 manipulation in C#, that class can be reused from any other
74 language that supports the CLI. You could create a class in C#,
75 subclass it in C++ and instantiate it in an Eiffel program.
77 A single object system, threading system, class libraries, and
78 garbage collection system can be shared across all these languages.
80 Q: Where can I find the specification for these technologies?
82 A: You can find the work-in-progress documentation from the T3G ECMA
85 <a href="http://www.dotnetexperts.com">http://www.dotnetexperts.com</a>
87 Q: Will you implement the .NET Framework SDK class libraries?
89 A: Yes, we will be implementing the APIs of the .NET Framework SDK
92 Q: Will you offer an ECMA-compliant set of class libraries?
94 A: Eventually we will. Our current focus is on interoperating
95 with the Microsoft SDK, but we will also offer an ECMA compliant
98 Q: What does the name "Mono" mean?
100 A: Mono is the word for `monkey' in Spanish. We like monkeys.
104 A: The JIT engine is usable on Intel x86 machines. An interpreter
105 can be used on other non-Intel x86 machines.
107 The class libraries are mature enough to run some real applications
108 (the compiler for instance, and every day more and more applications
109 are natively developed with Mono).
111 Q: When will you ship it?
113 A: Different parts of Mono will achieve usability at different stages,
114 once we are comfortable with the compiler, we will release "Mono Core",
115 which contains everything needed to develop applications with the base
116 class libraries. This should be available at some point during 2002.
118 Other higher level class libraries (ASP.NET, ADO.NET, Windows.Forms) will
119 be released when they become stable.
121 Q: What major components will you include in Mono?
123 A: Hopefully everything that Microsoft ships on their Framework
124 (ADO.NET, ASP.NET, Windows.Forms), and
125 we encourage third party developers to create reusable components that
126 work on both Mono and Windows.
128 Q: How can I contribute?
130 A: Check the <a href="contributing.html">contributing</a> section.
132 Q: Aren't you just copying someone else's work?
134 A: We are interested in providing the best tools for programmers to
135 develop applications for Free Operating Systems. We also want to help
136 provide the interoperability that will allow those systems to fit in
137 with other standards.
139 For more background, read the <a href="http://www.go-mono.com/rationale.html">Mono
140 Project white paper</a>.
143 Q: Miguel said once that Mono was being implemented in COBOL. Is that true?.
145 A: No. It was a joke.
148 <a name="ximian"></a>
150 ** The Ximian Role in the Mono Project
152 Q: Why is Ximian working on .NET?
154 A: Ximian is interested in providing the best tools for programmers to
155 develop applications for Free Operating Systems.
157 For more information, read the project <a
158 href="rationale.html">rationale</a> page.
160 Q: Will Ximian be able to take on a project of this size?
162 A: Of course not. Ximian a supporter of the Mono project, but the only way
163 to implement something of this size is for the entire free software
164 community to get involved. Visit the <a href="contributing.html">contributing</a>
165 page if you'd like to help out.
167 Q: What pieces will Ximian be working on?
169 A: We will devote most of our resources to work on the pieces which are
170 on the critical path to release a development and execution
171 environment. Once the project is at a stage where it is useful in
172 the real world, it will achieve a critical mass of developers to
175 Q: Will Ximian offer Mono commercially?
177 A: When Mono is ready to be shipped Ximian will offer a commercial
178 support and services for Mono.
180 Q: Does Ximian provide consulting services around Mono?
182 A: Yes, Ximian does provide consulting services around Mono to
183 make it suitable to your needs. Porting the runtime engine,
184 customizing it, working on specific classes or tuning the code
185 for your particular needs.
187 Q: Will you wait until Mono is finished?
189 A: Mono will ship on various stages as they mature. Some people
190 require only a subset of the technologies, those will ship first.
192 More advanced features will take more time to develop. A support
193 timeline will be available in June 2002.
198 Q: How is Mono related to GNOME?
200 A: In a number of ways. This project was born out of the need of
201 providing improved tools for the GNOME community, and will use
202 existing components that have been developed for GNOME when they
203 are available. For example, we plan to use Gtk+ and Libart to
204 implement Winforms and the Drawing2D API and are considering
207 Q: Has the GNOME Foundation or the GNOME team adopted Mono?
209 A: Mono is too new to be adopted by those groups. We hope that the
210 tools that we will provide will be adopted by free software
211 programmers including the GNOME Foundation members and the GNOME
214 Q: Should GNOME programmers switch over to Mono now?
216 A: It is still far to early for discussions of "switching over." No
217 pieces of Mono will be ready within the next six months, and a
218 complete implementation is roughly one year away.
220 We encourage GNOME developers to continue using the existing tools,
221 libraries and components. Improvements made to GNOME will have an
222 impact on Mono, as they would be the "backend" for various classes.
224 Q: Will Mono include compatibility with Bonobo components? What is the
225 relationship between Mono and Bonobo?
227 A: Yes, we will provide a set of classes for implementing and using
228 Bonobo components from within Mono. Mono should allow you to write
229 Bonobo components more easily, just like .NET on Windows allows you
230 to export .NET components to COM.
232 Q: Does Mono depend on GNOME?
234 A: No, Mono does not depend on GNOME. We use a few packages produced by
235 the GNOME team like the `glib' library.
237 Q: But will I be able to build GNOME applications?
239 A: Yes, we will enable people to write GNOME applications using Mono.
244 Q: Will Mono enable GUI applications to be authored?
246 A: Yes, you will be able to build GUI applications. Indeed, that is our
247 main focus. We will provide both the Windows.Forms API and the Gtk# API.
249 Q: What is the difference between Gtk# and System.Windows.Forms?
251 A: Gtk# is a set of bindings for the Gtk+ toolkit for C# (and other
252 CIL-enabled languages). System.Windows.Forms is an API defined
253 by Microsoft to build GUI applications.
255 Q: Will I be able to run my smart clients on systems powered by Mono?
257 A: As long as your applications are 100% .NET and do not make use
258 of P/Invoke to call Win32 functions, your smart client applications
259 will run on Mono platforms.
261 Q: Where can I learn mora about Gtk#?
263 A: The following <a href="http://gtk-sharp.sourceforge.net>link</a> sends you to the page of the project.
265 Q: What can I do with Gtk#?.
267 A: Gtk# is becoming very usable and you can create applications and
268 applets like those you see in a GNOME desktop environment. It's
269 easy to install so it's worth a try.
271 Q: How can I compile my HelloWorld.cs which uses Gtk#?.
273 A: Try: mcs --unsafe -o HelloWorld.exe -r glib-sharp -r pango-sharp -r
274 atk-sharp -r gdk-sharp -r gtk-sharp -r gdk-imaging-sharp
279 ** Mono and Microsoft
281 Q: Is Microsoft helping Ximian with this project?
283 A: No. Ximian CTO Miguel de Icaza had a friendly conversation with
284 Microsoft software architect David Stutz, but that's about the
285 extent of the contact. Microsoft is interested in other
286 implementations of .NET and are willing to help make the ECMA spec
287 more accurate for this purpose.
289 Ximian representatives have also spoken with Sam Ruby at the ECMA
290 TG3 committee to discuss the same issues.
292 Q: Is Microsoft or Corel paying Ximian to do this?
296 Q: Do you fear that Microsoft will change the spec and render Mono
299 A: No. Microsoft proved with the CLI and the C# language that it was
300 possible to create a powerful foundation for many languages to
301 interoperate. We will always have that.
303 Even if changes happened in the platform which were undocumented,
304 the existing platform would a value on its own.
306 Q: Are you writing Mono from the ECMA specs?
308 A: Yes, we are writing them from the ECMA specs and the published
309 materials in print about .NET.
311 Q: If my applications use Mono, will I have to pay a service fee?
313 A: No. Mono is not related to Microsoft's initiative of
314 software-as-a-service.
316 Q: Is the Mono Project is related to the Microsoft Hailstorm effort? Is
317 Ximian endorsing Hailstorm?
319 A: No. The Mono Project is focused on providing a compatible set of
320 tools for the Microsoft .NET development platform. It does not
321 address, require, or otherwise endorse the MS Passport-based
322 Hailstorm single sign-on system that is part of Windows XP and
325 Q: Will Mono or .NET applications depend on Microsoft Passport?
327 A: No. MS Passport is unrelated to running .NET compatible applications
328 produced with the Mono tools. The only thing you will need is a
329 just-in-time compiler (JIT).
331 Q: What is a 100% .NET application?
333 A: A `100% .NET application' is one that only uses the APIs defined
334 under the System namespace and does not use PInvoke. These
335 applications would in theory run unmodified on Windows, Linux,
336 HP-UX, Solaris, MacOS X and others.
338 Q: If Microsoft will release a port of their .NET platform under the
339 `Shared Source' license, why should I bother with anything else?
341 A: The Shared Source implementation will be expensive and its uses
342 will be tightly restricted, especially for commercial use. We are
343 working towards an implementation that will grant a number of
344 important rights to recipients: use for any purpose,
345 redistribution, modification, and redistribution of modifications.
347 This is what we call <a
348 href="http://www.gnu.org/philosophy/free-sw.html">Free Software</a>
350 Q: Is Mono a free implementation of Passport?
352 A: No. Mono is just a runtime, a compiler and a set of class
355 Q: Will the System.Web.Security.PassportIdentity class mean
356 that my software will depend on Passport?
358 A: No. Applications may use that API to contact a Passport site, but
359 are not required to do so.
361 As long as your application does not use Passport, you will not
364 Q: Will Mono running on Linux make Passport available for Linux?
366 A: No. However, the Passport toolkit for Linux-based web servers is
367 available from Microsoft.
369 Q: Will Mono allow me to run Microsoft Office on Linux?
371 A: No, it will not. Microsoft Office is a Windows application. To
372 learn more about running Windows applications on Intel Unix systems
373 refer to <a href="http://www.winehq.com">the Wine Project</a>.
375 <a name="pnpproject"></a>
376 ** Mono and Portable.NET
378 Q: What are the differences between Mono and Portable.NET?
380 A: Most of Mono is being written using C#, with only
381 a few parts written in C (The JIT engine, the runtime, the
382 interfaces to the garbage collection system).
384 It is easier to describe what is unique about Mono:
386 <li> A self-hosting C# compiler written in C#, which is clean, easy
389 <li> A multi-platform runtime engine: both a JIT engine and an
390 interpreter exist. The JIT engine runs currently on x86
391 systems, while the interpreter works on Sparc, StrongARM and
394 <li> Supports Linux, Windows and Solaris at this point.
396 <li> The JIT engine is written using a portable instruction
397 selector which not only generates good code (we are told
398 that we are faster than Rotor, but it is hard to tell) but
399 is also the foundation to retarget the JIT engine to other
402 The system employed is described in various compiler
403 books and it is very similar to what is described in the
404 book that covers LCC, the Ansi C retargetable C compiler.
406 <li> The JIT engine supports inlining, constant folding and propagation,
408 <li> Full support for remoting in the runtime, but the class
409 libraries are still behind.
411 <li> The C# compiler, the JIT engine and the class libraries are
412 mature enough that the whole system is self-hosting, ie, that
413 it can be fully developed with itself at this point.
415 <li> We are not yet done, and there is a lot of work left to be
418 <li> We have a great community of developers, without which Mono
419 would not be possible.
421 <li> We will provide an ahead of time compilation mode in the
425 <a name="webservices"></a>
428 Q: How is Mono related to Web Services?
430 A: Mono is only related to Web Services in that it will implement the
431 same set of classes that have been authored in the .NET Framework
432 to simplify and streamline the process of building Web Services.
434 But most importantly, Mono is an Open Source implementation of the
437 Q: Can I author Web Services with Mono?
439 A: You will be able to write Web Services on .NET that run on Mono and
442 Q: If Mono implements the SDK classes, will I be able to write and
443 execute .NET Web Services with it?
445 A: Yes. When the project is finished, you will be able to use the
446 same technologies that are available through the .NET Framework SDK
447 on Windows to write Web Services.
449 Q: What about Soup? Can I use Soup without Mono?
451 A: Soup is a library for GNOME applications to create SOAP servers and
452 SOAP clients, and can be used without Mono. You can browse the
453 source code for soup using <a
454 href="http://cvs.gnome.org/bonsai">GNOME's Bonsai</a>.
458 A: Yes. The CLI contains enough information about a class that
459 exposing it to other RPC systems (like CORBA) is really simple, and
460 does not even require support from an object.
462 We will be implementing CORBA interoperation as an extension to the
463 Mono classes so that we can integrate with Bonobo, just like
464 Microsoft provides COM interoperation classes and support
467 Q: Can I serialize my objects to other things other than XML?
469 A: Yes, although the serializing tools have not yet been planned, and
470 you would probably have to implement them yourself.
472 Q: Will Mono use ORBit?
474 A: No. Mono will be using a new implementation of CORBA that isn't still started.
477 ** Development Tools and Issues
479 Q: Will it be possible to use the CLI features without using bytecodes
482 A: Yes. The CLI engine will be made available as a shared library.
483 The garbage collection engine, the threading abstraction, the
484 object system, the dynamic type code system and the JIT will be
485 available for C developers to integreate with their applications if
488 Q: Will you have new development tools?
490 A: With any luck, Free Software enthusiasts will contribute tools to
491 improve the developer environment. These tools could be developed
492 initially using the Microsoft implementation of the CLI and then
493 executed later with Mono.
495 Q: What kind of rules make the Common Intermediate Language useful for
498 A: The main rule is that the stack in the CLI is not a general purpose
499 stack. You are not allowed to use it for other purposes than
500 computing values and passing arguments to functions or return
503 At any given call or return instruction, the types on the stack
504 have to be the same independently of the flow of execution of your
507 Q: Is it true that the CIL is ideal for JITing and not efficient for
510 A: The CIL is better suited to be JITed than JVM byte codes, but you
511 can interpret them as trivially as you can interpret JVM byte
514 Q: Isn't it a little bit confusing to have the name of "XSP" (the same
515 as in the Apache Project) for the ASP.NET support in Mono?.
517 A: In Mono, xsp is just the name of the C# code generator for ASP.NET
518 pages. In the Apache Project, it is a term for the "eXtensible Server
519 Pages" technology so as they are very different things, they don't
522 Q: What about using something like Jabber instead of the System.Messaging
525 A: In short, MSMQ is not something like Jabber, but asynchronous messaging
526 through queues. Usefull queues do more than serialize messages, they are
527 also platform bridges.
529 Q: Are you supporting XMLDocument and relatives?.
531 A: Currently, we aren't implementing them yet. It would require updates to
532 most of the XmlNode derivatives so it's not a trivial task. We are
533 currently focusing on getting XPath support working.
535 Q: Is there any plan to develop an aspx server for Mono?.
537 A: The webserver turned out to be very simple compared to the rest of the
538 work. Gonzalo has got the page generator mostly done (a module called
539 xsp, who has nothing to do with the XSP term used in the Apache Project).
540 Patrik has done a lot of the work to get the ProcessRequest to work.
541 You can try to help in the final touches to the System.Web classes and
542 writing regression tests for the widgets we have.
547 Q: Is Mono supporting ASP.NET?
549 A: Yes. The development of the support for ASP.NET comes in various stages,
550 here is what Gonzalo has been working on: 1. The Parser. 2. Getting the
551 parser to generate output compatible with ASP.NET. 3. Running the sample
552 output with the real Microsoft runtime but using our generated page. 4.
553 Running the sample with our classes with the .NET runtime. 5. Running
554 our sample code with our classes with our runtime. This is the process
555 we are following. Currently Gonzalo has reached point 3.
557 Q: I have heard that their is a webserver developed with Mono. Is it true?.
559 A: Yes. You can find it <a href="http://home.adelphia.net/~aljames/webserver.htm">here</a>
560 Read the README for more info.
565 Q: Why don't you use Java? After all, there are many languages that
568 A: You can get very good tools for doing Java development on free
569 systems right now. <a href="http://www.redhat.com">Red Hat</a> has
570 contributed a <a href="http://gcc.gnu.org">GCC</a> <a
571 href="http://gcc.gnu.org/java">frontend for Java</a> that can take
572 Java sources or Java byte codes and generate native executables; <a
573 href="http://www.transvirtual.com">Transvirtual</a> has implemented
574 <a href="http://www.kaffe.org">Kaffe</a> a JIT engine for Java;
575 Intel also has a Java VM called <a
576 href="http://www.intel.com/research/mrl/orp">ORP</a>.
578 The JVM is not designed to be a general purpose virtual machine.
579 The Common Intermediate Language (CIL), on the other hand, is
580 designed to be a target for a
581 wide variety of programming languages, and has a set of rules
582 designed to be optimal for JITers.
584 Q: Could Java target the CLI?
586 A: Yes, Java could target the CLI. We have details on a <a
587 href="ideas.html#guavac">project</a> that someone could take on to
590 Microsoft has an implemenation of the Java language called J# that
591 can target the CIL execution engine.
593 Q: Is it possible to write a JVM byte code to CIL convertor?
595 A: Yes, it is possible. Here are a few starting point:
598 * A byte code representation is really a flattened forest of
599 trees. Look at the Mono JIT engine to see how we compute
600 the basic blocks (this is used to figure out the "trees").
602 The forest is just an array of trees.
604 Indeed, run the JIT engine with -d (mono -d prog.exe) and
605 you will see how these trees look like.
607 You will have to do something similar for Java.
609 * Each "forest of trees" has a meaning. This meaning can now
610 be translated into the equivalent "meaning" in CLR-land.
613 Q: Could mono become a hybrid cil/java platform?
615 A: No. It is quite far from the philosophy of the project. The idea of Mono
616 is, to have only _one_ VM, on which all can run. And if there existing a
617 binary-converter from Java-.class to IL and if there existing something
618 like J-Sharp on Mono, you can write programs in Java, which than can run
619 on Mono. You do not need two bindings (like your example: GTK-Sharp _and_
620 Java-Gnome). You need only _one_ of it (GTK-Sharp). Thats the idea of Mono.
621 An other point is, that there are no people, who use OpenSource-JVMs. They
622 all prefer Suns original. But for Unix there don't exist a .NET-Framework.
623 So it is possible, that in the future Mono is the standard .NET for unixes.
625 <a name="extending"></a>
628 Q: Would you allow other classes other than those in the
631 A: Yes. The Microsoft class collection is very big, but it is by no
632 means complete. It would be nice to have a port of `Camel' (the
633 Mail API used by Evolution inspired by Java Mail) for Mono
636 You might also want to look into implementing CORBA for Mono. Not
637 only because it would be useful, but because it sounds like a fun
638 thing to do, given the fact that the CLI is such a type rich
641 For more information on extending Mono, see our <a
642 href="ideas.html">ideas</a> page.
644 Q: Do you plan to Embrace and Extend .NET?
646 A: Embracing a good technology is good. Extending technologies in
647 incompatible ways is bad for the users, so we do not plan on
648 extending the technologies.
650 If you have innovative ideas, and want to create new classes, we
651 encourage you to make those classes operate correctly well in both
654 <a name="portability"></a>
657 Q: Will Mono only work on Linux?
659 A: Currently, we are doing our work on Linux-based systems and
660 Windows. We do not expect many Linux-isms in the code, so it
661 should be easy to port Mono to other UNIX variants.
663 Q: What about Mono on non Linux-based systems?
665 A: Our main intention at Ximian is to be able to develop GNOME
666 applications with Mono, but if you are interested in providing a
667 port of the Winform classes to other platforms (frame buffer or
668 MacOS X for example), we would gladly integrate them, as long
669 they are under an open source license.
671 Q: What operating systems/CPUs do you support
673 A: Mono currently runs on Linux, Windows, Solaris and FreeBSD.
674 There is a JIT engine available for x86 processors that can
675 generate code and optimizations tailored for a particular CPU.
677 Interpreters exist for the SPARC, PowerPC and StrongARM cpus.
679 Q: Does Mono run on Windows?
681 A: Yes. The Compiler and the runtime both run on Windows.
683 Q: When will mono and mcs compile on Linux?.
685 A: That happend a long time ago. Know you can download and compile
686 them or even install them from already made binary packages for
687 Windows and for Linux (RPM/DEB).
689 Q: Will I require Cygwin to run mono?
691 A: No. While you'll need it to compile it, it runs without cygwin and does not even require cygwin1.dll
693 Q: Will Mono depend on GNOME?
695 A: It will depend only if you are using a particular assembly (for
696 example, for doing GUI applications). If you are just interested
697 in Mono for implementing a `Hello World Enterprise P2P Web
698 Service', you will not need any GNOME components.
701 ** Reusing Existing Code
703 Q: What projects will you reuse or build upon?
705 A: We want to get Mono in the hands of programmers soon. We are
706 interested in reusing existing open source software.
708 Q: What about Intel's research JIT framework, ORP?
710 A: At this time, we are investigating whether we can use elements of
711 ORP for Mono. ORP is a research JIT engine that has a clearly
712 defined API that splits the JIT from the GC system and the actual
713 byte code implementation.
715 We are using some pieces of ORP (Their code generation interface)
716 and we use it as a source of inspiration for optimizations. Paolo
717 and Dietmar consider ORP as being one of the best JIT engines out
718 there (and their research work and papers are very useful if you are
719 interested in JIT technology).
721 Q: What about using GNU Lightning?
723 A: We are not using GNU Lightning. Our JIT is using an instruction
724 selector based on tree-pattern matching, and a code generation
725 interface that is very tied to the current architecture.
730 Q: Are you working on a GCC front-end to C#? A GCC backend that will
731 generate CIL images? What about making a front-end to GCC that
732 takes CIL images and generates native code?
734 A: We are currently seeking volunteers for those projects.
735 Visit the <a href="contributing.html">contributing</a> section if
738 Q: But would this work around the GPL in the GCC compiler and allow
739 people to work on non-free front-ends?
741 A: People can already do this by targeting the JVM byte codes (there
742 are about 130 compilers for various languages that target the JVM).
744 Q: Why are you writing a JIT engine instead of a front-end to GCC?
746 A: We want the JIT engine and runtime engine because they will be able
747 to execute CIL executables generated on Windows, and so no recompilation
750 <a name="performance"></a>
753 Q: How fast will Mono be?
755 A: We can not predict the future, but a conservative estimate is that
756 it would be at least `as fast as other JIT engines'.
758 We would like to ship various JIT engines with Mono, just like
759 Microsoft has done with their .NET development platform. We could
760 provide a faster, JIT for fast load times but lower performance,
761 and an and an optimizing JIT that would be slower at generating
762 code but produce more optimal output.
764 The CIL has some advantages over the Java byte code: it is really
765 an intermediate representation and there are a number of
766 restrictions on how you can emit CIL code that simplify creating
769 For example, on the CIL, the stack is not really an abstraction
770 available for the code generator to use at will. Rather, it is a
771 way of creating a postfix representation of the parsed tree. At
772 any given call point or return point, the contents of the stack are
773 expected to contain the same object types independently of how the
774 instruction was reached.
776 <a name="licensing"></a>
779 Q: Will I be able to write proprietary applications that run with
782 A: Yes. The licensing scheme is planned to allow proprietary
783 developers to write applications with Mono.
785 Q: What license or licenses are you using for the Mono Project?
787 A: The C# Compiler is released under the terms of the <a
788 href="http://www.opensource.org/licenses/gpl-license.html">GNU GPL</a>. The runtime
789 libraries are under the <a
790 href="http://www.opensource.org/licenses/lgpl-license.html">GNU
791 Library GPL</a>. And the class libraries are released
792 under the terms of the <a
793 href="http://www.opensource.org/licenses/mit-license.html">MIT X11</a>
796 Q: I would like to contribute code to Mono under a particular
797 license. What licenses will you accept?
799 A: We will have to evaluate the licenses for compatibility first,
800 but as a general rule, we will accept the code under the same
801 terms of the "container" module.
803 <a name="patents></a>
806 Q: Could patents be used to completely disable Mono (either submarine
807 patents filed now, or changes made by Microsoft specifically to
808 create patent problems)?
810 A: No. First, its basic functional capabilities have pre-existed too
811 long to be held up by patents. The basic components of Mono are
812 technologically equivalent to Sun's Java technology, which has been
813 around for years. Mono will also implement multi-language and
814 multi-architecture support, but there are previous technologies
815 such as UCSD p-code and ANDF that also support multiple languages
816 using a common intermediate language. The libraries are similar
817 to other language's libraries, so again, they're too similar to
818 be patentable in large measure.
820 However, if Microsoft does patent some technology, then our plan is
821 to either (1) work around it, (2) chop out patented pieces, (3)
822 find prior art that would render the patent useless.
824 Not providing a patented capability would weaken the
825 interoperability, but it would still provide the free software /
826 open source software community with good development tools, which
827 is the primary reason for developing Mono.
830 ** Miscellaneous Questions
832 Q: You say that the CLI allows multiple languages to execute on the
833 same environment. Isn't this the purpose of CORBA?
835 A: The key difference between CORBA (and COM) and the CLI is that the
836 CLI allows "data-level interoperability" because every
837 language/component uses the same data layout and memory management.
839 This means you can operate directly upon the datatypes that someone
840 else provides, without having to go via their interfaces. It also
841 means you don't have to "marshall" (convert) parameters (data
842 layouts are the same, so you can just pass components directly) and
843 you don't have to worry about memory managment, because all
844 languages/components share the same garbage collector and address
845 space. This means much less copying and no need for reference
848 Q: Will you support COM?
850 A: The runtime will support XPCOM on Unix systems and COM on Windows.
851 Most of the code for dynamic trampolines exists already.
853 Q: Will Ximian offer certifications on Mono or related technologies?.
855 A: It's possible. But there is no plan about this. So the short answer is no.
857 Q: Are there any Boehm's gc binaries?
859 A: Yes. You can find them <a href="http://java.thn.htu.se/~toor/">here</a>