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="#winforms">Mono and WinForms</a><br>
6 <a href="#msft">Mono and Microsoft</a><br>
7 <a href="#pnpproject">Mono and the Portable.NET Project</a><br>
8 <a href="#webservices">Web Services</a><br>
9 <a href="#asp">Mono and ASP.NET</a><br>
10 <a href="#devel">Development Tools and Issues</a><br>
11 <a href="#java">Mono and Java</a><br>
12 <a href="#extending">Extending Mono</a><br>
13 <a href="#portability">Portability</a><br>
14 <a href="#reuse">Reusing Existing Code</a><br>
15 <a href="#gcc">Mono and GCC</a><br>
16 <a href="#performance">Performance</a><br>
17 <a href="#licensing">Licensing</a><br>
18 <a href="#patents">Patents</a><br>
19 <a href="#etc">Miscellaneous Questions</a><br>
25 Q: What is Mono exactly?
27 A: The Mono Project is an open development initiative sponsored by
28 Ximian that is working to develop an open source, Unix
29 version of the Microsoft .NET development platform. Its objective
30 is to enable Unix developers to build and
31 deploy cross-platform .NET Applications. The project will
32 implement various technologies developed by Microsoft that have now
33 been submitted to the ECMA for standardization.
35 Q: What is the difference between Mono and the .NET Initiative?
37 A: The ".NET Initiative" is a somewhat nebulous company-wide effort by
38 Microsoft, one part of which is a cross-platform development
39 framework. Mono is an implementation of the development framework,
40 but not an implementation of anything else related to the .NET
41 Initiative, such as Passport, software-as-a-service, or
44 Q: What technologies are included in Mono?
46 A: Mono contains a number of components useful for building new
50 * A Common Language Infrastructure (CLI) virtual
51 machine that contains a class loader, Just-in-time
52 compiler, and a garbage collecting runtime.
54 * A class library that can work with any language
55 which works on the CLR.
57 * A compiler for the C# language. In the future we
58 might work on other compilers that target the Common
63 Windows has compilers that target the virtual machine from <a
64 href="http://msdn.microsoft.com/net/thirdparty/default.asp#lang">a
65 number of languages:</a> Managed C++, Java Script, Eiffel,
66 Component Pascal, APL, Cobol, Oberon, Perl, Python, Scheme,
67 Smalltalk, Standard ML, Haskell, Mercury and Oberon.
69 The CLR and the Common Type System (CTS) enables applications and
70 libraries to be written in a collection of different languages that
73 This means for example that if you define a class to do algebraic
74 manipulation in C#, that class can be reused from any other
75 language that supports the CLI. You could create a class in C#,
76 subclass it in C++ and instantiate it in an Eiffel program.
78 A single object system, threading system, class libraries, and
79 garbage collection system can be shared across all these languages.
81 Q: Where can I find the specification for these technologies?
83 A: You can find the work-in-progress documentation from the T3G ECMA
86 <a href="http://www.dotnetexperts.com">http://www.dotnetexperts.com</a>
88 Q: Will you implement the .NET Framework SDK class libraries?
90 A: Yes, we will be implementing the APIs of the .NET Framework SDK
93 Q: Will you offer an ECMA-compliant set of class libraries?
95 A: Eventually we will. Our current focus is on interoperating
96 with the Microsoft SDK, but we will also offer an ECMA compliant
99 Q: What does the name "Mono" mean?
101 A: Mono is the word for `monkey' in Spanish. We like monkeys.
105 A: The JIT engine is usable on Intel x86 machines. An interpreter
106 can be used on other non-Intel x86 machines.
108 The class libraries are mature enough to run some real applications
109 (the compiler for instance, and every day more and more applications
110 are natively developed with Mono).
112 Q: When will you ship it?
114 A: Different parts of Mono will achieve usability at different stages,
115 once we are comfortable with the compiler, we will release "Mono Core",
116 which contains everything needed to develop applications with the base
117 class libraries. This should be available at some point during 2002.
119 Other higher level class libraries (ASP.NET, ADO.NET, Windows.Forms) will
120 be released when they become stable.
122 Q: What major components will you include in Mono?
124 A: Hopefully everything that Microsoft ships on their Framework
125 (ADO.NET, ASP.NET, Windows.Forms), and
126 we encourage third party developers to create reusable components that
127 work on both Mono and Windows.
129 Q: How can I contribute?
131 A: Check the <a href="contributing.html">contributing</a> section.
133 Q: Aren't you just copying someone else's work?
135 A: We are interested in providing the best tools for programmers to
136 develop applications for Free Operating Systems. We also want to help
137 provide the interoperability that will allow those systems to fit in
138 with other standards.
140 For more background, read the <a href="http://www.go-mono.com/rationale.html">Mono
141 Project white paper</a>.
144 Q: Miguel said once that Mono was being implemented in COBOL. Is that true?.
146 A: No. It was a joke.
149 <a name="ximian"></a>
151 ** The Ximian Role in the Mono Project
153 Q: Why is Ximian working on .NET?
155 A: Ximian is interested in providing the best tools for programmers to
156 develop applications for Free Operating Systems.
158 For more information, read the project <a
159 href="rationale.html">rationale</a> page.
161 Q: Will Ximian be able to take on a project of this size?
163 A: Of course not. Ximian a supporter of the Mono project, but the only way
164 to implement something of this size is for the entire free software
165 community to get involved. Visit the <a href="contributing.html">contributing</a>
166 page if you'd like to help out.
168 Q: What pieces will Ximian be working on?
170 A: We will devote most of our resources to work on the pieces which are
171 on the critical path to release a development and execution
172 environment. Once the project is at a stage where it is useful in
173 the real world, it will achieve a critical mass of developers to
176 Q: Will Ximian offer Mono commercially?
178 A: When Mono is ready to be shipped Ximian will offer a commercial
179 support and services for Mono.
181 Q: Does Ximian provide consulting services around Mono?
183 A: Yes, Ximian does provide consulting services around Mono to
184 make it suitable to your needs. Porting the runtime engine,
185 customizing it, working on specific classes or tuning the code
186 for your particular needs.
188 Q: Will you wait until Mono is finished?
190 A: Mono will ship on various stages as they mature. Some people
191 require only a subset of the technologies, those will ship first.
193 More advanced features will take more time to develop. A support
194 timeline will be available in June 2002.
199 Q: How is Mono related to GNOME?
201 A: In a number of ways. This project was born out of the need of
202 providing improved tools for the GNOME community, and will use
203 existing components that have been developed for GNOME when they
204 are available. For example, we plan to use Gtk+ and Libart to
205 implement Winforms and the Drawing2D API and are considering
208 Q: Has the GNOME Foundation or the GNOME team adopted Mono?
210 A: Mono is too new to be adopted by those groups. We hope that the
211 tools that we will provide will be adopted by free software
212 programmers including the GNOME Foundation members and the GNOME
215 Q: Should GNOME programmers switch over to Mono now?
217 A: It is still far to early for discussions of "switching over." No
218 pieces of Mono will be ready within the next six months, and a
219 complete implementation is roughly one year away.
221 We encourage GNOME developers to continue using the existing tools,
222 libraries and components. Improvements made to GNOME will have an
223 impact on Mono, as they would be the "backend" for various classes.
225 Q: Will Mono include compatibility with Bonobo components? What is the
226 relationship between Mono and Bonobo?
228 A: Yes, we will provide a set of classes for implementing and using
229 Bonobo components from within Mono. Mono should allow you to write
230 Bonobo components more easily, just like .NET on Windows allows you
231 to export .NET components to COM.
233 Q: Does Mono depend on GNOME?
235 A: No, Mono does not depend on GNOME. We use a few packages produced by
236 the GNOME team like the `glib' library.
238 Q: But will I be able to build GNOME applications?
240 A: Yes, we will enable people to write GNOME applications using Mono.
245 Q: Will Mono enable GUI applications to be authored?
247 A: Yes, you will be able to build GUI applications. Indeed, that is our
248 main focus. We will provide both the Windows.Forms API and the Gtk# API.
250 Q: What is the difference between Gtk# and System.Windows.Forms?
252 A: Gtk# is a set of bindings for the Gtk+ toolkit for C# (and other
253 CIL-enabled languages). System.Windows.Forms is an API defined
254 by Microsoft to build GUI applications.
256 Q: Will I be able to run my smart clients on systems powered by Mono?
258 A: As long as your applications are 100% .NET and do not make use
259 of P/Invoke to call Win32 functions, your smart client applications
260 will run on Mono platforms.
262 Q: Where can I learn mora about Gtk#?
264 A: The following <a href="http://gtk-sharp.sourceforge.net>link</a> sends you to the page of the project.
266 Q: What can I do with Gtk#?.
268 A: Gtk# is becoming very usable and you can create applications and
269 applets like those you see in a GNOME desktop environment. It's
270 easy to install so it's worth a try.
272 Q: How can I compile my HelloWorld.cs which uses Gtk#?.
274 A: Try: mcs --unsafe -o HelloWorld.exe -r glib-sharp -r pango-sharp -r
275 atk-sharp -r gdk-sharp -r gtk-sharp -r gdk-imaging-sharp
278 <a name="winforms"></a>
281 Q: Can you tell me why aren't you implementing WinForms?.
283 A: (This is based in an original mail to mono-list written by Miguel de
284 Icaza. You should read it for completion, but the core part is here).
286 First, Windows.Forms is packed with quirks and is not that great of a
287 toolkit in the first place. Up to the point of the unconfirmed rumor
288 that Microsoft is working on a replacement for it.
290 Once the runtime is done, we will very likely start contributing to
291 the Gtk# project ourselves, and we will likely start doing feasibility
292 work on getting Mono used by Gnome developers: full gnome apps and
293 extending existing applications.
295 Those interested in hacking on Windows.Forms are welcome to do so,
296 but Ximian will not likely look at it in the near future; if there is
297 enough demand, or I can be convinced that Windows.Forms is useful for
298 something Ximian might re-evaluate our resource allocation for this
301 By doing native ports, we could use the same API on all those systems.
302 Also, Gtk is mature enough, we know this because we have built an entire
303 desktop (and all sorts of very window system-specific hacks), and we
304 have built a bunch of productivity applications with it.
308 Someone mentioned VCL. The only problem with the VCL is that it can
309 only be used for GPL applications (or I guess you could license it from
310 Borland for your app), and would have to be ported from Delphi to C#
311 (or someone would have to write a CIL compiler for it).
313 Q: What about doing something like the eclipse project (www.eclipse.org)?
315 A: The Eclipse toolkit is not a general purpose toolkit. It will require a
316 lot of work before it is such a thing. It is a toolkit used to
317 implement a development environment.
321 ** Mono and Microsoft
323 Q: Is Microsoft helping Ximian with this project?
325 A: No. Ximian CTO Miguel de Icaza had a friendly conversation with
326 Microsoft software architect David Stutz, but that's about the
327 extent of the contact. Microsoft is interested in other
328 implementations of .NET and are willing to help make the ECMA spec
329 more accurate for this purpose.
331 Ximian representatives have also spoken with Sam Ruby at the ECMA
332 TG3 committee to discuss the same issues.
334 Q: Is Microsoft or Corel paying Ximian to do this?
338 Q: Do you fear that Microsoft will change the spec and render Mono
341 A: No. Microsoft proved with the CLI and the C# language that it was
342 possible to create a powerful foundation for many languages to
343 interoperate. We will always have that.
345 Even if changes happened in the platform which were undocumented,
346 the existing platform would a value on its own.
348 Q: Are you writing Mono from the ECMA specs?
350 A: Yes, we are writing them from the ECMA specs and the published
351 materials in print about .NET.
353 Q: If my applications use Mono, will I have to pay a service fee?
355 A: No. Mono is not related to Microsoft's initiative of
356 software-as-a-service.
358 Q: Is the Mono Project is related to the Microsoft Hailstorm effort? Is
359 Ximian endorsing Hailstorm?
361 A: No. The Mono Project is focused on providing a compatible set of
362 tools for the Microsoft .NET development platform. It does not
363 address, require, or otherwise endorse the MS Passport-based
364 Hailstorm single sign-on system that is part of Windows XP and
367 Q: Will Mono or .NET applications depend on Microsoft Passport?
369 A: No. MS Passport is unrelated to running .NET compatible applications
370 produced with the Mono tools. The only thing you will need is a
371 just-in-time compiler (JIT).
373 Q: What is a 100% .NET application?
375 A: A `100% .NET application' is one that only uses the APIs defined
376 under the System namespace and does not use PInvoke. These
377 applications would in theory run unmodified on Windows, Linux,
378 HP-UX, Solaris, MacOS X and others.
380 Q: If Microsoft will release a port of their .NET platform under the
381 `Shared Source' license, why should I bother with anything else?
383 A: The Shared Source implementation will be expensive and its uses
384 will be tightly restricted, especially for commercial use. We are
385 working towards an implementation that will grant a number of
386 important rights to recipients: use for any purpose,
387 redistribution, modification, and redistribution of modifications.
389 This is what we call <a
390 href="http://www.gnu.org/philosophy/free-sw.html">Free Software</a>
392 Q: Is Mono a free implementation of Passport?
394 A: No. Mono is just a runtime, a compiler and a set of class
397 Q: Will the System.Web.Security.PassportIdentity class mean
398 that my software will depend on Passport?
400 A: No. Applications may use that API to contact a Passport site, but
401 are not required to do so.
403 As long as your application does not use Passport, you will not
406 Q: Will Mono running on Linux make Passport available for Linux?
408 A: No. However, the Passport toolkit for Linux-based web servers is
409 available from Microsoft.
411 Q: Will Mono allow me to run Microsoft Office on Linux?
413 A: No, it will not. Microsoft Office is a Windows application. To
414 learn more about running Windows applications on Intel Unix systems
415 refer to <a href="http://www.winehq.com">the Wine Project</a>.
417 <a name="pnpproject"></a>
418 ** Mono and Portable.NET
420 Q: What are the differences between Mono and Portable.NET?
422 A: Most of Mono is being written using C#, with only
423 a few parts written in C (The JIT engine, the runtime, the
424 interfaces to the garbage collection system).
426 It is easier to describe what is unique about Mono:
428 <li> A self-hosting C# compiler written in C#, which is clean, easy
431 <li> A multi-platform runtime engine: both a JIT engine and an
432 interpreter exist. The JIT engine runs currently on x86
433 systems, while the interpreter works on Sparc, StrongARM and
436 <li> Supports Linux, Windows and Solaris at this point.
438 <li> The JIT engine is written using a portable instruction
439 selector which not only generates good code (we are told
440 that we are faster than Rotor, but it is hard to tell) but
441 is also the foundation to retarget the JIT engine to other
444 The system employed is described in various compiler
445 books and it is very similar to what is described in the
446 book that covers LCC, the Ansi C retargetable C compiler.
448 <li> The JIT engine supports inlining, constant folding and propagation,
450 <li> Full support for remoting in the runtime, but the class
451 libraries are still behind.
453 <li> The C# compiler, the JIT engine and the class libraries are
454 mature enough that the whole system is self-hosting, ie, that
455 it can be fully developed with itself at this point.
457 <li> We are not yet done, and there is a lot of work left to be
460 <li> We have a great community of developers, without which Mono
461 would not be possible.
463 <li> We will provide an ahead of time compilation mode in the
467 <a name="webservices"></a>
470 Q: How is Mono related to Web Services?
472 A: Mono is only related to Web Services in that it will implement the
473 same set of classes that have been authored in the .NET Framework
474 to simplify and streamline the process of building Web Services.
476 But most importantly, Mono is an Open Source implementation of the
479 Q: Can I author Web Services with Mono?
481 A: You will be able to write Web Services on .NET that run on Mono and
484 Q: If Mono implements the SDK classes, will I be able to write and
485 execute .NET Web Services with it?
487 A: Yes. When the project is finished, you will be able to use the
488 same technologies that are available through the .NET Framework SDK
489 on Windows to write Web Services.
491 Q: What about Soup? Can I use Soup without Mono?
493 A: Soup is a library for GNOME applications to create SOAP servers and
494 SOAP clients, and can be used without Mono. You can browse the
495 source code for soup using <a
496 href="http://cvs.gnome.org/bonsai">GNOME's Bonsai</a>.
500 A: Yes. The CLI contains enough information about a class that
501 exposing it to other RPC systems (like CORBA) is really simple, and
502 does not even require support from an object.
504 We will be implementing CORBA interoperation as an extension to the
505 Mono classes so that we can integrate with Bonobo, just like
506 Microsoft provides COM interoperation classes and support
509 Q: Can I serialize my objects to other things other than XML?
511 A: Yes, although the serializing tools have not yet been planned, and
512 you would probably have to implement them yourself.
514 Q: Will Mono use ORBit?
516 A: No. Mono will be using a new implementation of CORBA that isn't still started.
519 ** Development Tools and Issues
521 Q: Will it be possible to use the CLI features without using bytecodes
524 A: Yes. The CLI engine will be made available as a shared library.
525 The garbage collection engine, the threading abstraction, the
526 object system, the dynamic type code system and the JIT will be
527 available for C developers to integreate with their applications if
530 Q: Will you have new development tools?
532 A: With any luck, Free Software enthusiasts will contribute tools to
533 improve the developer environment. These tools could be developed
534 initially using the Microsoft implementation of the CLI and then
535 executed later with Mono.
537 Q: What kind of rules make the Common Intermediate Language useful for
540 A: The main rule is that the stack in the CLI is not a general purpose
541 stack. You are not allowed to use it for other purposes than
542 computing values and passing arguments to functions or return
545 At any given call or return instruction, the types on the stack
546 have to be the same independently of the flow of execution of your
549 Q: Is it true that the CIL is ideal for JITing and not efficient for
552 A: The CIL is better suited to be JITed than JVM byte codes, but you
553 can interpret them as trivially as you can interpret JVM byte
556 Q: Isn't it a little bit confusing to have the name of "XSP" (the same
557 as in the Apache Project) for the ASP.NET support in Mono?.
559 A: In Mono, xsp is just the name of the C# code generator for ASP.NET
560 pages. In the Apache Project, it is a term for the "eXtensible Server
561 Pages" technology so as they are very different things, they don't
564 Q: What about using something like Jabber instead of the System.Messaging
567 A: In short, MSMQ is not something like Jabber, but asynchronous messaging
568 through queues. Usefull queues do more than serialize messages, they are
569 also platform bridges.
571 Q: Are you supporting XMLDocument and relatives?.
573 A: Currently, we aren't implementing them yet. It would require updates to
574 most of the XmlNode derivatives so it's not a trivial task. We are
575 currently focusing on getting XPath support working.
577 Q: Is there any plan to develop an aspx server for Mono?.
579 A: The webserver turned out to be very simple compared to the rest of the
580 work. Gonzalo has got the page generator mostly done (a module called
581 xsp, who has nothing to do with the XSP term used in the Apache Project).
582 Patrik has done a lot of the work to get the ProcessRequest to work.
583 You can try to help in the final touches to the System.Web classes and
584 writing regression tests for the widgets we have.
586 Q: Is there any way I can develop the class libraries using linux yet?
588 A: Yes. Some class libraries can be developed on Linux. Search for
589 Paolo's post (he lists which classes can be compiled fine now).
591 Q: Is there any way I can install a known working copy of mono in /usr,
592 and an experimental copy somewhere else, and have both copies use
593 their own libraries? (I'm still not very good at library paths in
596 A: Yes. Just use two installation prefixes.
602 Q: Is Mono supporting ASP.NET?
604 A: Yes. The development of the support for ASP.NET comes in various stages,
605 here is what Gonzalo has been working on: 1. The Parser. 2. Getting the
606 parser to generate output compatible with ASP.NET. 3. Running the sample
607 output with the real Microsoft runtime but using our generated page. 4.
608 Running the sample with our classes with the .NET runtime. 5. Running
609 our sample code with our classes with our runtime. This is the process
610 we are following. Currently Gonzalo has reached point 5.
615 Q: Why don't you use Java? After all, there are many languages that
618 A: You can get very good tools for doing Java development on free
619 systems right now. <a href="http://www.redhat.com">Red Hat</a> has
620 contributed a <a href="http://gcc.gnu.org">GCC</a> <a
621 href="http://gcc.gnu.org/java">frontend for Java</a> that can take
622 Java sources or Java byte codes and generate native executables; <a
623 href="http://www.transvirtual.com">Transvirtual</a> has implemented
624 <a href="http://www.kaffe.org">Kaffe</a> a JIT engine for Java;
625 Intel also has a Java VM called <a
626 href="http://www.intel.com/research/mrl/orp">ORP</a>.
628 The JVM is not designed to be a general purpose virtual machine.
629 The Common Intermediate Language (CIL), on the other hand, is
630 designed to be a target for a
631 wide variety of programming languages, and has a set of rules
632 designed to be optimal for JITers.
634 Q: Could Java target the CLI?
636 A: Yes, Java could target the CLI. We have details on a <a
637 href="ideas.html#guavac">project</a> that someone could take on to
640 Microsoft has an implemenation of the Java language called J# that
641 can target the CIL execution engine.
643 Q: Is it possible to write a JVM byte code to CIL convertor?
645 A: Yes, it is possible. Here are a few starting point:
648 * A byte code representation is really a flattened forest of
649 trees. Look at the Mono JIT engine to see how we compute
650 the basic blocks (this is used to figure out the "trees").
652 The forest is just an array of trees.
654 Indeed, run the JIT engine with -d (mono -d prog.exe) and
655 you will see how these trees look like.
657 You will have to do something similar for Java.
659 * Each "forest of trees" has a meaning. This meaning can now
660 be translated into the equivalent "meaning" in CLR-land.
663 Q: Could mono become a hybrid cil/java platform?
665 A: No. It is quite far from the philosophy of the project. The idea of Mono
666 is, to have only _one_ VM, on which all can run. And if there existing a
667 binary-converter from Java-.class to IL and if there existing something
668 like J-Sharp on Mono, you can write programs in Java, which than can run
669 on Mono. You do not need two bindings (like your example: GTK-Sharp _and_
670 Java-Gnome). You need only _one_ of it (GTK-Sharp). Thats the idea of Mono.
671 An other point is, that there are no people, who use OpenSource-JVMs. They
672 all prefer Suns original. But for Unix there don't exist a .NET-Framework.
673 So it is possible, that in the future Mono is the standard .NET for unixes.
675 <a name="extending"></a>
678 Q: Would you allow other classes other than those in the
681 A: Yes. The Microsoft class collection is very big, but it is by no
682 means complete. It would be nice to have a port of `Camel' (the
683 Mail API used by Evolution inspired by Java Mail) for Mono
686 You might also want to look into implementing CORBA for Mono. Not
687 only because it would be useful, but because it sounds like a fun
688 thing to do, given the fact that the CLI is such a type rich
691 For more information on extending Mono, see our <a
692 href="ideas.html">ideas</a> page.
694 Q: Do you plan to Embrace and Extend .NET?
696 A: Embracing a good technology is good. Extending technologies in
697 incompatible ways is bad for the users, so we do not plan on
698 extending the technologies.
700 If you have innovative ideas, and want to create new classes, we
701 encourage you to make those classes operate correctly well in both
704 Q: Is there any way I can develop the class libraries using linux yet?
706 A: Yes. Some class libraries can be developed on Linux. Search for
707 Paolo's post (he lists which classes can be compiled fine now).
709 Q: Is there any way I can install a known working copy of mono in /usr,
710 and an experimental copy somewhere else, and have both copies use
711 their own libraries? (I'm still not very good at library paths in
714 A: Yes. Just use two installation prefixes.
717 <a name="portability"></a>
720 Q: Will Mono only work on Linux?
722 A: Currently, we are doing our work on Linux-based systems and
723 Windows. We do not expect many Linux-isms in the code, so it
724 should be easy to port Mono to other UNIX variants.
726 Q: What about Mono on non Linux-based systems?
728 A: Our main intention at Ximian is to be able to develop GNOME
729 applications with Mono, but if you are interested in providing a
730 port of the Winform classes to other platforms (frame buffer or
731 MacOS X for example), we would gladly integrate them, as long
732 they are under an open source license.
734 Q: What operating systems/CPUs do you support
736 A: Mono currently runs on Linux, Windows, Solaris and FreeBSD.
737 There is a JIT engine available for x86 processors that can
738 generate code and optimizations tailored for a particular CPU.
740 Interpreters exist for the SPARC, PowerPC and StrongARM cpus.
742 Q: Does Mono run on Windows?
744 A: Yes. The Compiler and the runtime both run on Windows.
746 Q: When will mono and mcs compile on Linux?.
748 A: That happend a long time ago. Know you can download and compile
749 them or even install them from already made binary packages for
750 Windows and for Linux (RPM/DEB).
752 Q: Will I require Cygwin to run mono?
754 A: No. While you'll need it to compile it, it runs without cygwin and does not even require cygwin1.dll
756 Q: Will Mono depend on GNOME?
758 A: It will depend only if you are using a particular assembly (for
759 example, for doing GUI applications). If you are just interested
760 in Mono for implementing a `Hello World Enterprise P2P Web
761 Service', you will not need any GNOME components.
763 Q: Is anyone working on porting Mono to IA-64?
765 A: Nobody is working on such port.
767 Q: If I were about to start a Mono port to IA-64,would the same lburg code
768 generator work for IA-64 also? or anything else need to be used for code
769 generation(as the processor architecture is totally different from IA32)
771 A: The lburg approach can be use for any processor architecture. But you might
772 think in another better approach.
775 ** Reusing Existing Code
777 Q: What projects will you reuse or build upon?
779 A: We want to get Mono in the hands of programmers soon. We are
780 interested in reusing existing open source software.
782 Q: What about Intel's research JIT framework, ORP?
784 A: At this time, we are investigating whether we can use elements of
785 ORP for Mono. ORP is a research JIT engine that has a clearly
786 defined API that splits the JIT from the GC system and the actual
787 byte code implementation.
789 We are using some pieces of ORP (Their code generation interface)
790 and we use it as a source of inspiration for optimizations. Paolo
791 and Dietmar consider ORP as being one of the best JIT engines out
792 there (and their research work and papers are very useful if you are
793 interested in JIT technology).
795 Q: What about using GNU Lightning?
797 A: We are not using GNU Lightning. Our JIT is using an instruction
798 selector based on tree-pattern matching, and a code generation
799 interface that is very tied to the current architecture.
801 Q: Will I be able to use Microsoft SQL Server 2000 or will I need to switch
802 to a specific Open Source Database. Will I need to recode?
804 A: There should not be any need to recode.
806 Q: What do I need to watch out for when programming in VB.NET so that I'm
807 sure to be able to run those apps on Linux?
809 A: Not making any PInvoke or DLL calls should and not using anything in
810 the Microsoft.* namespaces should suffice. Also do not use any
811 Methods/Classes marked as "This type/method supports the .NET Framework
812 infrastructure and is not intended to be used directly from your code."
813 even if you know what these classes/methods do.
815 Q: Will built-in reporting be supported for crystal reports? This is a
816 heavily used part of our system.
818 A: Probably not. Crystal Reports are propriety. Someone may try to emulate
819 the behaviour, but no-one has yet volunteered.
821 Q: Who about writing to the registry? As I understand it, Linux does not have
822 a counterpart to the registry. Should I avoid relying on that feature?
824 A: Try to avoid it. Although there would be a emulation for registry in
825 Mono too. GNOME does have a registry like mechanism for configuration. But
826 Even if gnome has a configuration system similar to the registry, the keys
827 will not be equal, so you will probably end up having to do some runtime
828 detection, and depending on this load an assembly that has your
829 platform-specific hacks.
831 Q: System.Data.SqlClient with FreeTDS, will you port parts of these to C# and
834 A: if their license is compatible with mono's, yes, we'd think about porting
835 them. If not, we'll continue with the plan of using FreeTDS.
840 Q: Are you working on a GCC front-end to C#? A GCC backend that will
841 generate CIL images? What about making a front-end to GCC that
842 takes CIL images and generates native code?
844 A: We are currently seeking volunteers for those projects.
845 Visit the <a href="contributing.html">contributing</a> section if
848 Q: But would this work around the GPL in the GCC compiler and allow
849 people to work on non-free front-ends?
851 A: People can already do this by targeting the JVM byte codes (there
852 are about 130 compilers for various languages that target the JVM).
854 Q: Why are you writing a JIT engine instead of a front-end to GCC?
856 A: We want the JIT engine and runtime engine because they will be able
857 to execute CIL executables generated on Windows, and so no recompilation
860 <a name="performance"></a>
863 Q: How fast will Mono be?
865 A: We can not predict the future, but a conservative estimate is that
866 it would be at least `as fast as other JIT engines'.
868 We would like to ship various JIT engines with Mono, just like
869 Microsoft has done with their .NET development platform. We could
870 provide a faster, JIT for fast load times but lower performance,
871 and an and an optimizing JIT that would be slower at generating
872 code but produce more optimal output.
874 The CIL has some advantages over the Java byte code: it is really
875 an intermediate representation and there are a number of
876 restrictions on how you can emit CIL code that simplify creating
879 For example, on the CIL, the stack is not really an abstraction
880 available for the code generator to use at will. Rather, it is a
881 way of creating a postfix representation of the parsed tree. At
882 any given call point or return point, the contents of the stack are
883 expected to contain the same object types independently of how the
884 instruction was reached.
886 <a name="licensing"></a>
889 Q: Will I be able to write proprietary applications that run with
892 A: Yes. The licensing scheme is planned to allow proprietary
893 developers to write applications with Mono.
895 Q: What license or licenses are you using for the Mono Project?
897 A: The C# Compiler is released under the terms of the <a
898 href="http://www.opensource.org/licenses/gpl-license.html">GNU GPL</a>. The runtime
899 libraries are under the <a
900 href="http://www.opensource.org/licenses/lgpl-license.html">GNU
901 Library GPL</a>. And the class libraries are released
902 under the terms of the <a
903 href="http://www.opensource.org/licenses/mit-license.html">MIT X11</a>
906 Q: I would like to contribute code to Mono under a particular
907 license. What licenses will you accept?
909 A: We will have to evaluate the licenses for compatibility first,
910 but as a general rule, we will accept the code under the same
911 terms of the "container" module.
913 <a name="patents></a>
916 Q: Could patents be used to completely disable Mono (either submarine
917 patents filed now, or changes made by Microsoft specifically to
918 create patent problems)?
920 A: No. First, its basic functional capabilities have pre-existed too
921 long to be held up by patents. The basic components of Mono are
922 technologically equivalent to Sun's Java technology, which has been
923 around for years. Mono will also implement multi-language and
924 multi-architecture support, but there are previous technologies
925 such as UCSD p-code and ANDF that also support multiple languages
926 using a common intermediate language. The libraries are similar
927 to other language's libraries, so again, they're too similar to
928 be patentable in large measure.
930 However, if Microsoft does patent some technology, then our plan is
931 to either (1) work around it, (2) chop out patented pieces, (3)
932 find prior art that would render the patent useless.
934 Not providing a patented capability would weaken the
935 interoperability, but it would still provide the free software /
936 open source software community with good development tools, which
937 is the primary reason for developing Mono.
940 ** Miscellaneous Questions
942 Q: You say that the CLI allows multiple languages to execute on the
943 same environment. Isn't this the purpose of CORBA?
945 A: The key difference between CORBA (and COM) and the CLI is that the
946 CLI allows "data-level interoperability" because every
947 language/component uses the same data layout and memory management.
949 This means you can operate directly upon the datatypes that someone
950 else provides, without having to go via their interfaces. It also
951 means you don't have to "marshall" (convert) parameters (data
952 layouts are the same, so you can just pass components directly) and
953 you don't have to worry about memory managment, because all
954 languages/components share the same garbage collector and address
955 space. This means much less copying and no need for reference
958 Q: Will you support COM?
960 A: The runtime will support XPCOM on Unix systems and COM on Windows.
961 Most of the code for dynamic trampolines exists already.
963 Q: Will Ximian offer certifications on Mono or related technologies?.
965 A: It's possible. But there is no plan about this. So the short answer is no.
967 Q: Are there any Boehm's gc binaries?
969 A: Yes. You can find them <a href="http://java.thn.htu.se/~toor/">here</a>
971 Q: I have get into trouble when trying to build the site in my Linux box, what
974 A: Try to change the line "./mono-rss.exe ../index deploy/index.rss" for
975 "mono ./mono-rss.exe ../index deploy/index.rss"
977 Q: How can I report a bug?
979 A: The best thing is to track down the bug and provide a simple test to
980 reproduce the bug. You can then add the bug to bugzilla:
981 http://bugzilla.ximian.com/enter_bug.cgi or simply send it to
982 mono-list@ximian.com.
984 Q: Does mcs support the same command line options as the MS C#
987 A: The Mono C# compiler on CVS now supports the same command line
988 arguments as the Microsoft C# compiler does.