1 <a href="#basics">Basics</a><br>
2 <a href="#novell">The Novell 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="#platforms">Mono platforms</a><br>
7 <a href="#compatibility">Compatibility</a></br>
8 <a href="#pnpproject">Mono and the Portable.NET Project</a><br>
9 <a href="#webservices">Web Services</a><br>
10 <a href="#asp">Mono and ASP.NET</a><br>
11 <a href="#ado">Mono and ADO.NET</a><br>
12 <a href="#monodoc">MonoDoc</a><br>
13 <a href="#devel">Development Tools and Issues</a><br>
14 <a href="#java">Mono and Java</a><br>
15 <a href="#extending">Extending Mono</a><br>
16 <a href="#portability">Portability</a><br>
17 <a href="#reuse">Reusing Existing Code</a><br>
18 <a href="#gcc">Mono and GCC</a><br>
19 <a href="#performance">Performance</a><br>
20 <a href="#licensing">Licensing</a><br>
21 <a href="#patents">Patents</a><br>
22 <a href="#etc">Miscellaneous Questions</a><br>
23 <a href="#problems">Mono Common Problems</a><br>
26 href="http://www.es.gnome.org/documentacion/articulos/mono-puf/mono-puf/">Spanish
27 translation</a> is also available
32 Q: What is Mono exactly?
34 A: The Mono Project is an open development initiative sponsored by
35 Ximian that is working to develop an open source, Unix
36 version of the Microsoft .NET development platform. Its objective
37 is to enable Unix developers to build and
38 deploy cross-platform .NET Applications. The project will
39 implement various technologies developed by Microsoft that have now
40 been submitted to the ECMA for standardization.
42 The Mono project has also sparked a lot of interest in developing
43 C#-based components, libraries and frameworks. Today Mono is not
44 limited to implement the .NET Framework, but also contains other
45 components. Some of the components of the Mono platform were
46 developed by the Mono team, and some others we have incorporated
47 from other open source efforts, the most important ones:
51 href="http://remoting-corba.sourceforge.net/">Remoting.CORBA</a>: A
52 CORBA implementation for Mono.
54 <li>Ginzu: An implementation on top of Remoting for the <a
55 href="http://www.zeroc.com">ICE</a> stack
57 <li><a href="http://gtk-sharp.sf.net">Gtk#</a>: Bindings for
58 the popular Gtk+ GUI toolkit for Unix and Windows systems.
59 Other bindings are available: Diacanvas-Sharp and MrProject.
62 href="http://www.icsharpcode.net/OpenSource/SharpZipLib/Default.aspx">#ZipLib</a>:
63 A library to manipulate various kinds of compressed files and
64 archives (Zip and tar).
66 <li>GlGen (available from the Mono CVS): Bindings for OpenGL.
68 <li>Mono.LDAP: LDAP access for .NET apps.
70 <li>Mono.Data: We ship support for Postgress, MySql, Sybase,
71 DB2, SqlLite, Tds (SQL server protocol) and Oracle databases.
73 <li>Mono.Cairo: Bindings for the <a
74 href="http://www.cairographics.org">Cairo</a> rendering
75 engine (Our System.Drawing is implemented on top of this).
77 <li>Mono.Posix: Bindings for building POSIX applications using
80 <li>Mono.Http: Support for creating custom, embedded HTTP
81 servers and common HTTP handlers for your applications.
84 Q: What is the difference between Mono and the .NET Initiative?
86 A: The ".NET Initiative" is a somewhat nebulous company-wide effort by
87 Microsoft, one part of which is a cross-platform development
88 framework. Mono is an implementation of the development framework,
89 but not an implementation of anything else related to the .NET
90 Initiative, such as Passport or software-as-a-service.
92 Q: What technologies are included in Mono?
94 A: Mono contains a number of components useful for building new
98 * A Common Language Infrastructure (CLI) virtual
99 machine that contains a class loader, Just-in-time
100 compiler, and a garbage collecting runtime.
102 * A class library that can work with any language
103 which works on the CLR. Both .NET compatible class
104 libraries as well as Mono-provided class libraries
107 * A compiler for the C# language. In the future we
108 might work on other compilers that target the Common
113 Windows has compilers that target the virtual machine from <a
114 href="http://msdn.microsoft.com/net/thirdparty/default.asp#lang">a
115 number of languages:</a> Managed C++, Java Script, Eiffel,
116 Component Pascal, APL, Cobol, Perl, Python, Scheme,
117 Smalltalk, Standard ML, Haskell, Mercury and Oberon.
119 The CLR and the Common Type System (CTS) enables applications and
120 libraries to be written in a collection of different languages that
123 This means for example that if you define a class to do algebraic
124 manipulation in C#, that class can be reused from any other
125 language that supports the CLI. You could create a class in C#,
126 subclass it in C++ and instantiate it in an Eiffel program.
128 A single object system, threading system, class libraries, and
129 garbage collection system can be shared across all these languages.
131 Q: Where can I find the specification for these technologies?
133 A: You can find the information here:
136 C# <a href="http://www.ecma.ch/ecma1/STAND/ecma-334.htm">http://www.ecma.ch/ecma1/STAND/ecma-334.htm</a>
138 CLI <a href="http://www.ecma.ch/ecma1/STAND/ecma-335.htm">http://www.ecma.ch/ecma1/STAND/ecma-335.htm</a>
140 Q: Will you implement the .NET Framework SDK class libraries?
142 A: Yes, we will be implementing the APIs of the .NET Framework SDK
145 Q: Will you offer an ECMA-compliant set of class libraries?
147 A: Eventually we will. Our current focus is on inter-operating
148 with the Microsoft SDK, but we will also offer an ECMA compliant
149 subset of the libraries.
151 Q: What does the name "Mono" mean?
153 A: Mono is the word for `monkey' in Spanish. We like monkeys.
155 Q: Does Mono work today?
157 A: The execution engine works on various platforms, we support
158 Just-in-Time and Ahead-of-Time compilations on Intel x86 machines
161 The class libraries are mature enough to run various real
162 applications: our C# compiler, ASP.NET, and Gtk#-based
165 Q: When will you ship Mono?
167 A: Please see the <a href="mono-roadmap.html">Mono Roadmap</a> for
168 more details on the release plans.
170 Q: How can I contribute?
172 A: Check the <a href="contributing.html">contributing</a> section.
174 Q: Aren't you just copying someone else's work?
176 A: We are interested in providing the best tools for programmers to
177 develop applications for Free Operating Systems. We also want to help
178 provide the interoperability that will allow those systems to fit in
179 with other standards.
181 For more background, read the <a href="http://www.go-mono.com/rationale.html">Mono
182 Project white paper</a>.
185 Q: Miguel said once that Mono was being implemented in COBOL. Is that true?.
187 A: No. It was a joke.
190 <a name="novell"></a>
192 ** The Novell Role in the Mono Project
194 Q: Why is Novell working on .NET?
196 A: Novell is interested in providing the best tools for programmers to
197 develop applications for Free Operating Systems.
199 For more information, read the project <a
200 href="rationale.html">rationale</a> page.
202 Q: Will Novell be able to take on a project of this size?
204 A: Of course not. Novell is a supporter of the Mono project, but the only way
205 to implement something of this size is for the entire free software
206 community to get involved. Visit the <a href="contributing.html">contributing</a>
207 page if you'd like to help out.
209 Q: What pieces Novell be working on?
211 A: We will devote most of our resources to work on the pieces which are
212 on the critical path to release a development and execution
213 environment. Once the project is at a stage where it is useful in
214 the real world, it will achieve a critical mass of developers to
217 Q: Will Novell offer Mono commercially?
219 A: When Mono is ready to be shipped Ximian will offer a commercial
220 support and services for Mono. Mono components are also
221 available to be licensed commercially. For licensing details,
223 href="mailto:mono-licensing@ximian.com">mono-licensing@ximian.com</a>
225 Q: Does Novell provide consulting services around Mono?
227 A: Yes, Novell does provide consulting services around Mono to
228 make it suitable to your needs. Porting the runtime engine,
229 customizing it, working on specific classes or tuning the code
230 for your particular needs.
233 href="mailto:mono-licensing@ximian.com">mono-licensing@ximian.com</a>
234 for consulting services information.
236 Q: Will you wait until Mono is finished?
238 A: Mono will ship on various stages as they mature. Some people
239 require only a subset of the technologies, those will ship first,
240 see the <a href="mono-roadmap.html">Mono Roadmap</a> for details
245 Q: How is Mono related to GNOME?
247 A: In a number of ways. This project was born out of the need of
248 providing improved tools for the GNOME community, and will use
249 existing components that have been developed for GNOME when they
250 are available. For example, we plan to use Gtk+ and Libart to
251 implement Winforms and the Drawing2D API and are considering
254 Mono team members work actively on the <a
255 href="http://gtk-sharp.sf.net">Gtk#</a> project: a binding of the
256 GNOME class libraries for .NET and Mono.
258 Q: Has the GNOME Foundation or the GNOME team adopted Mono?
260 A: Mono is too new to be adopted by those groups. We hope that the
261 tools that we will provide will be adopted by free software
262 programmers including the GNOME Foundation members and the GNOME
265 Q: Should GNOME programmers switch over to Mono now?
267 A: It is still far to early for discussions of "switching over." No
268 pieces of Mono will be ready within the next six months, and a
269 complete implementation is roughly one year away.
271 We encourage GNOME developers to continue using the existing tools,
272 libraries and components. Improvements made to GNOME will have an
273 impact on Mono, as they would be the "back-end" for various classes.
275 Q: Will Mono include compatibility with Bonobo components? What is the
276 relationship between Mono and Bonobo?
278 A: Yes, we will provide a set of classes for implementing and using
279 Bonobo components from within Mono. Mono should allow you to write
280 Bonobo components more easily, just like .NET on Windows allows you
281 to export .NET components to COM.
283 Q: Does Mono depend on GNOME?
285 A: No, Mono does not depend on GNOME. We use a few packages produced by
286 the GNOME team like the `glib' library, we also use other
287 third-party open source libraries like Cairo and ICU.
289 Q: But will I be able to build GNOME applications?
291 A: Yes, we will enable people to write GNOME applications using Mono.
293 Q: Do you have C# bindings for GNOME?.
295 A: Yes, the <a href="http://gtk-sharp.sf.net">Gtk# project</a>
296 provides bindings for Gtk+, Gdk, Atk, libgnome, libgnomecanvas, and
297 libgnomeui. Other libraries under the GNOME framework will be
298 added on an as-needed (and as-requested) basis.
303 Q: Will Mono enable GUI applications to be authored?
305 A: Yes, you will be able to build GUI applications. Indeed, that is
306 our main focus. Today you can use Gtk# or #WT to develop GUI
307 applications, and support for Windows.Forms is underway.
309 Q: What is the difference between Gtk# and System.Windows.Forms?
311 A: Gtk# is a set of bindings for the Gtk+ toolkit for C# (and other
312 CIL-enabled languages), it integrates natively with the Gnome
313 desktop. System.Windows.Forms is an API defined by Microsoft to
314 build GUI applications.
316 Windows.Forms is currently being implemented on top of a modified
317 version of Wine that can be used as a library: WineLib.
319 Q: Why not implement System.Windows.Forms on top of Gtk# or Qt#?
323 Although it is possible to run simple Windows.Forms applications
324 with the Gtk#-based backend of Windows.Forms, it is very unlikely
325 that the implementation will ever implement everything needed for
326 full compatibility with Windows.Forms.
328 The reason is that Windows.Forms is not a complete toolkit, and to
329 work around this problem some of the underlying Win32 foundation is
330 exposed to the programmer in the form of exposing the Windows
331 message handler (WndProc). Any control can override this method.
332 Also developers often P/Invoke into Win32 to get to functionality
333 that was not wrapped.
335 To achieve full compatibility, we would have to emulate this, and
336 it would take too long.
338 For more details see the <a href="winforms.html">winforms page</a>
340 Q: Wine applications do not look like native applications, what are
341 you going to do about this?
343 A: We have already a few patches into our version of Windows.Forms
344 that makes Wine use the colors and font settings from your desktop,
345 improving the integration a lot. In the future, we will continue
346 to improve this interoperability scenario.
348 Q: Will I be able to run my smart clients on systems powered by Mono?
350 A: As long as your applications are 100% .NET and do not make use
351 of P/Invoke to call Win32 functions, your smart client applications
352 will run on Mono platforms.
354 Q: Where can I learn more about Gtk#?
356 A: The following <a href="http://gtk-sharp.sourceforge.net>link</a> sends you to the page of the project.
358 Q: What can I do with Gtk#?.
360 A: Gtk# is becoming very usable and you can create applications and
361 applets like those you see in a GNOME desktop environment. It's
362 easy to install so it's worth a try.
364 Q: How can I compile my HelloWorld.cs which uses Gtk#?.
366 A: Try: mcs -r:gtk-sharp HelloWorld.cs
368 Q: Is there any way how to connect DataAdapter to some GTK# controls?
370 A: There is a sample file called `DbClient' in gtk-sharp/samples that you
371 might to look at. It is a sample program in Gtk# that adds/updates/deletes
372 information on a Postgress database. When we have the new table/tree widgets,
373 I am sure someone would write an adapter for System.Data (in Gtk2 the
374 tree/list widgets are written using a view/model, so you only need to write
375 a model that maps to the database). You can have a look at
376 gtk-sharp/sample/DbClient, where there is a GTK# application that uses
377 System.Data. It does not use DataAdapter, but DataReader though.
379 Q: Do you have an estimate for when Windows.Forms will be released?
381 A: The plan currently is aimed at Q3/2004.
384 Q: Do you have a comparission chart about the various toolkit
387 A: A document explaining this is available at: <a
388 href="http://primates.ximian.com/~miguel/toolkits.html">http://primates.ximian.com/~miguel/toolkits.html</a>.
391 ** Mono and Microsoft
393 Q: Is Microsoft helping Ximian with this project?
395 A: There is no high level communication between Ximian and Microsoft
396 at this point, but engineers who work on .NET or the ECMA groups
397 have been very friendly, and very nice to answer our questions, or
398 clarify part of the specification for us.
400 Microsoft is interested in other implementations of .NET and are
401 willing to help make the ECMA spec more accurate for this purpose.
403 Ximian was also invited to participate in the ECMA committee
404 meetings for C# and the CLI.
406 Q: Are Microsoft or Corel paying Ximian to do this?
410 Q: Do you fear that Microsoft will change the spec and render Mono
413 A: No. Microsoft proved with the CLI and the C# language that it was
414 possible to create a powerful foundation for many languages to
415 inter-operate. We will always have that.
417 Even if changes happened in the platform which were undocumented,
418 the existing platform would a value on its own.
420 Q: Are you writing Mono from the ECMA specs?
422 A: Yes, we are writing them from the ECMA specs and the published
423 materials in print about .NET.
425 Q: If my applications use Mono, will I have to pay a service fee?
427 A: No. Mono is not related to Microsoft's initiative of
428 software-as-a-service.
430 Q: Is the Mono Project is related to the Microsoft Hailstorm effort? Is
431 Ximian endorsing Hailstorm?
433 A: No. The Mono Project is focused on providing a compatible set of
434 tools for the Microsoft .NET development platform. It does not
435 address, require, or otherwise endorse the MS Passport-based
436 Hailstorm single sign-on system that is part of Windows XP and
439 Q: Will Mono or .NET applications depend on Microsoft Passport?
441 A: No. MS Passport is unrelated to running .NET compatible applications
442 produced with the Mono tools. The only thing you will need is a
443 just-in-time compiler (JIT).
445 Q: If Microsoft will release a port of their .NET platform under the
446 `Shared Source' license, why should I bother with anything else?
448 A: The Shared Source implementation will be expensive and its uses
449 will be tightly restricted, especially for commercial use. We are
450 working towards an implementation that will grant a number of
451 important rights to recipients: use for any purpose,
452 redistribution, modification, and redistribution of modifications.
454 This is what we call <a
455 href="http://www.gnu.org/philosophy/free-sw.html">Free Software</a>
457 Q: Is Mono a free implementation of Passport?
459 A: No. Mono is just a runtime, a compiler and a set of class
462 Q: Will the System.Web.Security.PassportIdentity class mean
463 that my software will depend on Passport?
465 A: No. Applications may use that API to contact a Passport site, but
466 are not required to do so.
468 As long as your application does not use Passport, you will not
471 Q: Will Mono running on Linux make Passport available for Linux?
473 A: No. However, the Passport toolkit for Linux-based web servers is
474 available from Microsoft.
476 Q: Will Mono allow me to run Microsoft Office on Linux?
478 A: No, it will not. Microsoft Office is a Windows application. To
479 learn more about running Windows applications on Intel Unix systems
480 refer to <a href="http://www.winehq.com">the Wine Project</a>.
482 Q: Can mono run the WebMatrix?
484 A: No. That requires System.Windows.Forms support which is not
485 currently implemented.
487 Q: Does mono have something like Passport?
488 Will mono have a server side Passport/Similar framework for XSP as well as client classes?
490 A: Not yet, but the client side API for authentication is not the problem.
491 We will likely have a lot of other authentication APIs, like the Liberty
492 Alliance APIs. The problem is people on the web provider end that might use
493 this for authentication.
495 <a name="platforms"></a>
498 Q: What operating systems does Mono run on?
500 A: Mono is known to run on Linux, Unix and Windows systems.
502 Q: What architectures does Mono support?
504 A: Mono today ships with a Just-in-Time compiler for x86-based
505 systems. It is tested regularly on Linux, FreeBSD and Windows
506 (with the XP/NT core).
508 There is also an interpreter, which is slower that runs on the
509 s390, SPARC and PowerPC architectures.
511 Q: Can Mono run on Windows 9x, or ME editions?
513 A: Mono requires Unicode versions of Win32 APIs to run,
514 and only a handful of *W functions is supported under Win9x.
516 There is Microsoft Layer for Unicode that provides implementation
517 of these APIs on 9x systems.
519 Unfortunately it uses linker trick for delayed load that is not
520 supported by ld, so some sort of adapter is necessary.
522 You will need MSLU and one of the following libs to link Mono to
524 href="http://mono.eurosoft.od.ua/files/unimono.zip">http://mono.eurosoft.od.ua/files/unimono.zip</a>
525 or alternatively search the net for "libunicows".
527 No changes to Mono source code required, the only thing is to make
528 sure that linker will resolve imports to adapter library instead of
529 Win32 libs. This is achieved by inserting -lunimono before
530 -lkerner32/user32 in the linker's specs file.
532 Q: Why support Windows, when you can run the real thing?
534 A: There are various reasons:
537 <li> About half the contributors to Mono are Windows developers.
538 They have many different for contributing to the effort, and
539 we find it very important to let those developers run the runtime on Windows without forcing
540 them to use a new operating system.
542 <li> Supporting Windows helps us identify the portable portions
543 of Mono from the non-portable versions of it, helping Mono
544 become more portable in the future.
546 <li> Mono does not heavily modify the windows registry, update system DLLs,
547 install DLLs to the Windows/System32 path. Another words, I knew Mono would
548 not cause any legacy enterprise applications to stop working - and it
549 hasn't. However, our CIO er is againt it because of the changes that would
550 be made to Windows 2000, such as, affecting security.
553 <a name="compatibility"></a>
556 Q: Can Mono run applications developed with the Microsoft.NET framework?
558 A: Yes, Mono can run applications developed with the Microsoft .NET Framework
559 on Unix. There are a few caveats to keep in mind: Mono has not
560 been completed yet, so a few API calls might be missing; And in
561 some cases the Mono behavior *might* be incorrect.
563 Q: Will missing API entry points be implemented?
565 A: Yes, the goal of Mono is to implement precisely the .NET Framework
566 API (as well as compile-time selectable subsets, for those
567 interested in a lighter version of Mono).
569 Q: If the behavior of an API call is different, will you fix it?
571 A: Yes, we will. But we will need your assistance for this. If you find a bug
572 in the Mono implementation, please fill a bug report in <a
573 href="http://bugzilla.ximian.com">http://bugzilla.ximian.com</a>.
574 Do not assume we know about the problem, we might not, and using the bug tracking
575 system helps us organize the development process.
577 Q: Can I develop my applications on Windows, and deploy on a supported
578 Mono platform (like Linux)?
582 As of today, Mono is not 100% finished, so it is sometimes useful
583 to compile the code with Mono, to find out if your application
584 depends on unimplemented functionality.
586 Q: Will applications run out the box with Mono?
588 A: Sometimes they will. But sometimes a .NET application might invoke
589 Win32 API calls, or assume certain patterns that are not correct
590 for cross-platform applications.
592 Q: What is a 100% .NET application?
594 A: A `100% .NET application' is one that only uses the APIs defined
595 under the System namespace and does not use P/Invoke. These
596 applications would in theory run unmodified on Windows, Linux,
597 HP-UX, Solaris, MacOS X and others.
599 Note that this requirement also holds for all assemblies used by the
600 application. If one of them is Windows-specific, then the entire program
601 is not a 100% .NET application.
603 Furthermore, a 100% .NET application must not contain non-standard data
604 streams in the assembly. For example, Visual Studio .NET will insert a
605 <tt>#-</tt> stream into assemblies built under the "Debug" target.
606 This stream contains debugging information for use by Visual Studio .NET;
607 however, this stream can not be interpreted by Mono (unless you're willing
610 Thus, it is recommended that all Visual Studio .NET-compiled code be
611 compiled under the Release target before it is executed under Mono.
613 Q: Can I execute my Visual Studio .NET program (Visual Basic .NET, Visual C#,
614 Managed Extensions for C++, etc.) under Mono?
616 A: Yes, with some reservations.
618 The .NET program must either be a 100% .NET application, or (somehow) have
619 all dependent assemblies available on all desired platforms. (How to do so
620 is outside the bounds of this FAQ.)
622 Mono must also have an implementation for the .NET assemblies used. For
623 example the System.EnterpriseServices namespace is part of .NET, but it
624 has not been implemented in Mono. Thus, any applications using this
625 namespace will not run under Mono.
627 With regards to languages, C# applications tend to be most portable.
629 Visual Basic .NET applications are portable, but Mono's
630 Microsoft.VisualBasic.dll implementation is incomplete. It is recommended
631 to either avoid using this assembly in your own code, only use the
632 portions that Mono has implemented, or to help implement the missing
633 features. Additionally, you can set 'Option Strict On', which
634 eliminates the implicit calls to the unimplemented
635 Microsoft.VisualBasic.CompilerServices.ObjectType class.
636 (Thanks to Jörg Rosenkranz.)
638 Managed Extensions for C++ is least likely to operate under Mono. Mono
639 does not support mixed mode assemblies (that is, assemblies containing both
640 managed and unmanaged code, which Managed C++ can produce). You need a
641 fully-managed assembly to run under Mono, and getting the Visual C++ .NET
642 compiler to generate such an executable can be difficult. You need to use
643 only the .NET-framework assemblies, not the C libraries (you can't use
644 <b>printf</b>(3) for example.), and you need to use
645 the linker options <tt>/nodefaultlib /entry:main mscoree.lib</tt> in
646 addition to the <tt>/clr</tt> compiler flag. You can still use certain
647 compiler intrinsic functions (such as <b>memcpy</b>(3)) and the STL.
648 You should also see <a
649 href="http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vcmex/html/vcgrfconvertingmanagedextensionsforcprojectsfrommixed-modetopureil.asp"
650 >Converting Managed Extensions for C++ Projects from Mixed Mode to Pure
651 Intermediate Language</a> at MSDN.
652 Finally, you can use PEVERIFY.EXE from the .NET SDK to determine if the
653 assembly is fully managed.
655 Thanks to Serge Chaban for the linker flags to use.
657 <a name="pnpproject"></a>
658 ** Mono and Portable.NET
660 Q: What are the differences between Mono and Portable.NET?
662 A: Most of Mono is being written using C#, with only
663 a few parts written in C (The JIT engine, the runtime, the
664 interfaces to the garbage collection system).
666 It is easier to describe what is unique about Mono:
668 <li> An advanced native-code compilation engine: Both
669 just-in-time compilation (JIT) and pre-compilation of CIL
670 bytecodes into native code are supported.
672 <li> A foundation for code optimization: The new code generator in
673 Mono builds on the experience of our first JIT engine, and enables
674 us to implement various advanced compiler optimization
675 tricks. With an SSA-framework, plenty of new optimizations are possible.
677 The current list of optimizations are: Peephole postpass,
678 Branch optimizations, Inline method calls, Constant folding, Constant
679 propagation, Copy propagation, Dead code elimination, Linear scan
680 global reg allocation, Conditional moves, Emit per-domain code,
681 Instruction scheduling, Intrinsic method implementations, Tail
682 recursion and tail calls, Loop related optimizations, Fast x86 FP
683 compares, Leaf procedures optimizations
685 <li> A self-hosting C# compiler written in C#, which is clean, easy
688 <li> Focus on the .NET Framework: we are tracking down the .NET
689 Framework API definition, as we believe it is the API people
690 will be most familiar with.
692 <li> A multi-platform runtime engine: both a JIT engine and an
693 interpreter exist. The JIT engine runs currently on x86
694 systems, while the interpreter works on SPARC, StrongARM,
695 s390 and PowerPC systems.
697 Our new compilation engine is being ported to the PowerPC.
699 <li> Supports Linux, BSD, Windows and Solaris at this point.
701 <li> The JIT engine is written using a portable instruction
702 selector which not only generates good code but
703 is also the foundation to re-target the JIT engine to other
706 <li> Full support for remoting in the runtime.
708 <li> The C# compiler, the JIT engine and the class libraries are
709 mature enough that the whole system has been self-hosting
710 since April 2002. This means that we develop Mono
711 completely with itself at this point.
713 By forcing ourselves to use our own code to develop our
714 tools, we bug fix problems rapidly, and the system is
715 overall more robust and tested than if we did not.
717 <li> We have a great community of developers, without which Mono
718 would not be possible.
721 In general, Mono is more mature and complete since it has been used
722 to develop itself, which is a big motivator for stability and
723 correctness, while Portable.NET remains pretty much an untested
726 Q: I hear Mono keeps changing the P/Invoke API, why?
728 A: We are just fixing our implementation to be compatible with the
729 Microsoft implementation. In other words, the Mono P/Invoke API is
730 more complete when compared to the Portable.NET version, hence
731 various pieces of software that depend on this extended
732 functionality fail to work properly with Portable.NET.
734 <a name="webservices"></a>
737 Q: How is Mono related to Web Services?
739 A: Mono is only related to Web Services in that it will implement the
740 same set of classes that have been authored in the .NET Framework
741 to simplify and streamline the process of building Web Services.
743 But most importantly, Mono is an Open Source implementation of the
746 Q: Can I author Web Services with Mono?
748 A: You will be able to write Web Services on .NET that run on Mono and
751 Q: If Mono implements the SDK classes, will I be able to write and
752 execute .NET Web Services with it?
754 A: Yes. When the project is finished, you will be able to use the
755 same technologies that are available through the .NET Framework SDK
756 on Windows to write Web Services.
758 Q: What about Soup? Can I use Soup without Mono?
760 A: Soup is a library for GNOME applications to create SOAP servers and
761 SOAP clients, and can be used without Mono. You can browse the
762 source code for soup using <a
763 href="http://cvs.gnome.org/bonsai">GNOME's Bonsai</a>.
767 A: Yes. The CLI contains enough information about a class that
768 exposing it to other RPC systems (like CORBA) is really simple, and
769 does not even require support from an object.
771 <a href="http://remoting-corba.sourceforge.net/">Remoting.CORBA</a> is
772 a CORBA implementation that is gaining momentum.
774 Building an implementation of the Bonobo interfaces once this is ready
775 should be relatively simple.
777 Q: Can I serialize my objects to other things other than XML?
779 A: Yes, although the serializing tools have not yet been planned, and
780 you would probably have to implement them yourself.
782 Q: Will Mono use ORBit?
784 A: There are a few advantages in using ORBit, like reusing existing code
785 and leveraging all the work done on it. Michael Meeks has posted
786 a few <a href="http://lists.ximian.com/archives/public/mono-list/2002-September/008592.html">reasons</a>,
787 as well as some <a href="http://lists.ximian.com/archives/public/mono-list/2002-September/008657.html">ideas</a>
788 that could be used to reuse ORBit.
790 Most users are likely to choose a native .NET solution, like <a href="http://cvs.gnome.org/bonsai">Remoting.CORBA</a>
793 <a name="monodoc"></a>
798 A: MonoDoc is a graphical documentation browser for the Mono class
799 libraries. Currently, monodoc consists of a Gtk# application and is
800 in heavy development.
803 ** Development Tools and Issues
805 Q: I am having trouble compiling a new version of Mono from CVS, it
806 complains about my runtime being out of sync.
808 A: To upgrade your class libraries and compiler, see the
809 INSTALL.txt in the MCS directory.
811 The single biggest source of confusion seems to be the "Your
812 runtime is out of sync" messages. Realize that this is *normal*
813 while BUILDING. Think about it: you're building a new class
814 library with the old runtime. If the new class library references
815 a function that the old runtime knows nothing about, the runtime
816 system issues this warning.
818 Basically what needs to happen is for a new mono runtime to be
819 compiled, then the corlib class library be compiled, and once this
820 is done, install the new runtime, followed by corlib.
822 Once this is done, you can continue building your entire
825 For instance you just need to:
826 1.- Upgrade your Mono runtime (you might better do it with the
827 mono-build.sh script available in the <a
828 href="http://www.go-mono.com">download</a> page.
829 2.- Get the latest mono-lite tarball from the daily snapshots
830 <a href="http://www.go-mono.com/daily/">page</a>, unzip and
831 untar and copy all the dll files to your install path lib
832 directory (typically pointed by the $MONO_PATH variable).
833 Copy all the exe files to the install path bin directory.
834 3.- Then checkout or update your mcs CVS copy. Then follow
835 the steps described in mcs/INSTALL.txt.
837 Q: Will it be possible to use the CLI features without using byte codes
840 A: Yes. The CLI engine will be made available as a shared library.
841 The garbage collection engine, the threading abstraction, the
842 object system, the dynamic type code system and the JIT will be
843 available for C developers to integrate with their applications if
846 Q: Will you have new development tools?
848 A: With any luck, Free Software enthusiasts will contribute tools to
849 improve the developer environment. These tools could be developed
850 initially using the Microsoft implementation of the CLI and then
851 executed later with Mono.
853 We are recommending people to use and contribute to existing
854 projects like SharpDevelop, Anjuta and Eclipse.
856 Q: What kind of rules make the Common Intermediate Language useful for
859 A: The main rule is that the stack in the CLI is not a general purpose
860 stack. You are not allowed to use it for other purposes than
861 computing values and passing arguments to functions or return
864 At any given call or return instruction, the types on the stack
865 have to be the same independently of the flow of execution of your
868 Q: Is it true that the CIL is ideal for JITing and not efficient for
871 A: The CIL is better suited to be JITed than JVM byte codes, but you
872 can interpret them as trivially as you can interpret JVM byte
875 Q: Isn't it a little bit confusing to have the name of "XSP" (the same
876 as in the Apache Project) for the ASP.NET support in Mono?.
878 A: In Mono, xsp is just the name of the C# code generator for ASP.NET
879 pages. In the Apache Project, it is a term for the "eXtensible Server
880 Pages" technology so as they are very different things, they don't
883 Q: Is there any plan to develop an aspx server for Mono?.
885 A: The XSP reference server is available and you can also use mod_mono
888 Q: Is there any way I can develop the class libraries using Linux yet?
890 A: Yes. Mono has been self hosting since May 2002.
892 Q: Is there any way I can install a known working copy of mono in /usr,
893 and an experimental copy somewhere else, and have both copies use
894 their own libraries? (I'm still not very good at library paths in
897 A: Yes. Just use two installation prefixes.
899 Q: How should I write tests or a tests suite?
901 A: If you do a test suite for C#, you might want to keep it
902 independent of the Mono C# compiler, so that other compiler
903 implementations can later use it.
905 Q: Would it be too terrible to have another corlib signed as mscorlib?
907 A: We rename corlib to mscorlib also when saving the PE files, in fact,
908 the runtime can execute program created by mono just fine.
910 Q: Is it possible to build a C# file to some sort of intermediate format which
911 can linked into a final module, like the traditional .c -> .o -> .so path?
915 mcs /target:library file1.cs, mcs /target:library file2.cs,
916 mcs /target:exe file1.dll file2.dll /out:mybin.exe
918 Q: Is there any plans for implementing remoting in the near future?
920 A: The remoting infrastructure is in place. We have implementations
921 of the TcpChannel, HttpChannel and the Soap and Binary Formatters.
922 They are compatible with .NET.
924 However, some classes from the library may have a different binary
925 representation, because they may have a different internal data
926 structure, so for example you won't be able to exchange a Hastable
927 object between Mono and MS.NET. It should not be a problem if you
928 are using primitive types, arrays or your own classes. In any case,
929 could you post a test case?
932 Q: My C code uses the __stdcall which is not availble on Linux, how can I
933 make the code portable Windows/Unix across platforms?
935 A: Replace the __stdcall attribute with the STDCALL macro, and include this
936 in your C code for newer gcc versions:
939 #define STDCALL __attribute__((stdcall))
942 Q: I want to be able to execute Mono binaries, without having to use the "mono"
943 command. How can I do this?
945 A: From Carlos Perelló:
947 <i>I think that the best solution is the binfmt feature with the
948 wrapper that exists with Debian packages at:
950 <a href="http://www.debianplanet.org/mono/dists/unstable/main/source/admin/">http://www.debianplanet.org/mono/dists/unstable/main/source/admin/</a>
952 If you want use it with Big endian machines, you should apply a patch
953 (<a href="http://carlos.pemas.net/debian/mono/binfmt-detector-cli.c.diff">http://carlos.pemas.net/debian/mono/binfmt-detector-cli.c.diff</a>)
955 It works really good and lets you use wine also, it reads the .exe file
956 headers and check if it's a .net executable.
958 This way you just execute: ./my-cool-mono-application.exe and it works
959 without the need of any wrapper.</i>
961 Q: I see funny characters when I run programs, what is the problem?
963 A: (From Peter Williams and Gonzalo Paniagua):
965 This is Red Hat 9 (probably) using UTF8 on its console; the bytes are
966 the UTF8 endianness markers. You can do:
968 LC_ALL=C mono myexe.exe
970 And they wont show up.
972 Alternatively, you can do:
976 to enable UTF-8 on the console.
981 Q: Does Mono support ASP.NET?
985 Mono supports ASP.NET, we have shown an unmodified IBuySpy
986 installation running on Mono as well as various other programs. You can
987 try it yourself downloading the XSP server.
989 Q: Do I need install cygwin to work on ASP.NET in mono or Linux is enough since
990 it is self host right now.
994 Q: How can I run ASP.NET-based applications with Mono?
996 A: You need the Mono runtime and a hosting web server. Currently we distribute a
997 small web server called `xsp' which is used to debug applications, or you can choose
998 to use Daniel's Apache 2 module.
1000 Q: Any plan to make ASP.NET in mono works with Apache in Linux?.
1002 A: Daniel has authored an Apache2 Module for Mono that hosts the ASP.NET runtime
1003 and is available here: <a
1004 href="http://apacheworld.org/modmono/">http://apacheworld.org/modmono/</a>
1006 Q: Will you support Apache 1?
1008 A: Modules developed for Apache 2 are not compatible with Apache 1.3
1009 Daniel plans to support Apache 1.3 in the future but the current focus is on
1010 Apache 2, because of the better support for threading and Windows.
1012 Q: Can I run Apache 1 and Apache 2 on the same machine?
1014 You can always keep a copy of Apache 2 running in parallel with your Apache
1015 1.3 (either different port or using a reverse proxy).
1017 You can also bind the two servers to different IP addresses on the
1018 same physical machine.
1023 Q: What is the status of ADO.NET support?. Could I start migrating
1024 applications from MS.NET to Mono?.
1026 A: You could start right now using the ADO.NET support in mono, of course,
1027 if you want to help filling the missing gaps while you develop your app
1028 :-) Well, what I mean is that we're not that far to having full ADO.NET
1029 support in Mono, and we've got a lot of working things, so if we could
1030 get more help, we'd finish it really soon :-)
1032 Q: In developing the data architecture for the application are there and
1033 objects I should stay away from in order to insure the smoothest possible
1034 transition (minimum code rewrite) to Mono's ADO.NET implementation? (For
1035 example, strongly typed datasets versus untyped datasets, etc...)
1037 A: We are implementing all the classes in Microsoft .NET's System.Data, so
1038 you can be sure that things will work the same in Mono as with the Microsoft
1041 Q: Does Mono can to connect to Sybase by using Mono.Data.*?
1043 A: Yes. use Mono.Data.SybaseClient. First of all you have to create a
1044 SybaseConnection, and then, from it, use it as any other
1045 IDbConnection-based class.
1050 Q: Why don't you use Java? After all, there are many languages that
1053 A: You can get very good tools for doing Java development on free
1054 systems right now. <a href="http://www.redhat.com">Red Hat</a> has
1055 contributed a <a href="http://gcc.gnu.org">GCC</a> <a
1056 href="http://gcc.gnu.org/java">front-end for Java</a> that can take
1057 Java sources or Java byte codes and generate native executables; <a
1058 href="http://www.transvirtual.com">Transvirtual</a> has implemented
1059 <a href="http://www.kaffe.org">Kaffe</a> a JIT engine for Java;
1060 Intel also has a Java VM called <a
1061 href="http://www.intel.com/research/mrl/orp">ORP</a>.
1063 The JVM is not designed to be a general purpose virtual machine.
1064 The Common Intermediate Language (CIL), on the other hand, is
1065 designed to be a target for a
1066 wide variety of programming languages, and has a set of rules
1067 designed to be optimal for JITers.
1069 Q: Could Java target the CLI?
1071 A: Yes, Java could target the CLI, Microsoft's J# compiler does that.
1073 The <a href="http://weblog.ikvm.net/">IKVM</a> project builds a
1074 Java runtime that works on top of .NET and on top of Mono. IKVM is
1075 essentially a JIT compiler that translates from JVM bytecodes into
1076 CIL instructions, and then lets the native JIT engine take over.
1078 Q: Is it possible to write a JVM byte code to CIL converter?
1080 A: Yes, this is what <a href="http://weblog.ikvm.net">IKVM</a> does.
1082 Q: Could mono become a hybrid CIL/java platform?
1084 A: This can be obtained easily with IKVM.
1086 Q: Do you plan to implement a Javascript compiler?
1088 A: Yes. The beginnings of the JScript compiler can be found on CVS.
1089 Cesar coordinates this effort.
1091 Q: Can Mono or .NET share system classes (loaded from mscore.dll and other
1092 libs) or will it behave like Sun's Java VM?
1094 A: What you can do with mono is to load different applications in their own
1095 application domain: this is a feature of the CLR that allows sandboxing
1096 applications inside a single process space. This is usualy exploited to
1097 compartmentalize different parts of the same app, but it can also be
1098 effectively used to reduce the startup and memory overhead.
1099 Using different appdomains the runtime representation of types and
1100 methods is shared across applications.
1102 <a name="extending"></a>
1105 Q: Would you allow other classes other than those in the
1108 A: Yes. The Microsoft class collection is very big, but it is by no
1109 means complete. It would be nice to have a port of `Camel' (the
1110 Mail API used by Evolution inspired by Java Mail) for Mono
1113 You might also want to look into implementing CORBA for Mono. Not
1114 only because it would be useful, but because it sounds like a fun
1115 thing to do, given the fact that the CLI is such a type rich
1118 For more information on extending Mono, see our <a
1119 href="ideas.html">ideas</a> page.
1121 Q: Do you plan to Embrace and Extend .NET?
1123 A: Embracing a good technology is good. Extending technologies in
1124 incompatible ways is bad for the users, so we do not plan on
1125 making incompatible changes to the technologies.
1127 If you have innovative ideas, and want to create new classes, we
1128 encourage you to make those classes operate correctly well in both
1131 Today Mono ships with a number of extra libraries that were
1132 developed either by members of the Mono community, or other
1135 In some cases, we have found the bits from Microsoft to be
1136 incomplete, but we avoid breaking the API, instead we expose the
1137 missing functionality in new assemblies (See Mono.Security and
1140 Q: Is there any way I can develop the class libraries using Linux yet?
1142 A: Yes. Mono has been selfhosting since March 2002.
1144 Q: Is there any way I can install a known working copy of mono in /usr,
1145 and an experimental copy somewhere else, and have both copies use
1146 their own libraries? (I'm still not very good at library paths in
1149 A: Yes. Just use two installation prefixes.
1152 <a name="portability"></a>
1155 Q: Will Mono only work on Linux?
1157 A: Currently, we are doing our work on Linux-based systems and
1158 Windows. We do not expect many Linux-isms in the code, so it
1159 should be easy to port Mono to other UNIX variants.
1161 Q: What about Mono on non Linux-based systems?
1163 A: Our main intention at Ximian is to be able to develop GNOME
1164 applications with Mono, but if you are interested in providing a
1165 port of the Winforms classes to other platforms (frame buffer or
1166 MacOS X for example), we would gladly integrate them, as long
1167 they are under an open source license.
1169 Q: What operating systems/CPUs do you support
1171 A: Mono currently runs on Linux, Windows, Solaris, FreeBSD, HP-UX and
1174 There is a JIT engine available for x86 processors that can
1175 generate code and optimizations tailored for a particular CPU.
1177 Interpreters exist for the SPARC v8, SPARC v9, Itanium, HP-PA,
1178 PowerPC and StrongARM CPUs.
1180 Q: Does Mono run on Windows?
1182 A: Yes. You can get pre-compiled
1183 binaries from <a href="http://www.go-mono.com/download.html">http://www.go-mono.com/download.html</a>
1185 Q: Does Mono run on Linux?
1187 A: Yes. You can get pre-compiled
1188 binaries from <a href="http://www.go-mono.com/download.html">http://www.go-mono.com/download.html</a>
1190 Q: Will I require Cygwin to run mono?
1192 A: No. Cygwin is only required to build Mono.
1194 Q: Will Mono depend on GNOME?
1196 A: It will depend only if you are using a particular assembly (for
1197 example, for doing GUI applications). If you are just interested
1198 in Mono for implementing a `Hello World Enterprise P2P Web
1199 Service', you will not need any GNOME components.
1201 Q: Do you plan to port Rhino to C#?.
1203 A: Eto Demerzal has started a Rhino port to C#.
1205 Q: Has anyone succeeded in building a Mac version of the C# environment.
1206 If so can you explain how?
1208 A: You could try to check with the Darwin people, or the Fink people.
1209 Mono/C# is self hosting on Linux/PPC which is the hard part, so it
1210 should be relatively simple to get it to work on MacOS
1212 <a name="reuse"></a>
1213 ** Reusing Existing Code
1215 Q: What projects will you reuse or build upon?
1217 A: We want to get Mono in the hands of programmers soon. We are
1218 interested in reusing existing open source software.
1220 Q: Will I be able to use Microsoft SQL Server 2000 or will I need to switch
1221 to a specific Open Source Database. Will I need to recode?
1223 A: There is no need to rewrite your code as long as you keep using
1224 Microsoft SQL Server. If you want to use an open source database,
1225 you might need to make changes to your code.
1227 Q: What do I need to watch out for when programming in VB.NET so that I'm
1228 sure to be able to run those apps on Linux?
1230 A: Not making any P/Invoke or DLL calls should and not using anything in
1231 the Microsoft.* namespaces should suffice. Also do not use any
1232 Methods/Classes marked as "This type/method supports the .NET Framework
1233 infrastructure and is not intended to be used directly from your code."
1234 even if you know what these classes/methods do.
1236 Q: Will built-in reporting be supported for crystal reports? This is a
1237 heavily used part of our system.
1239 A: . Crystal Reports are propriety. Someone may try to emulate
1240 the behavior, but no-one has yet volunteered.
1242 Q: Who about writing to the registry? As I understand it, Linux does not have
1243 a counterpart to the registry. Should I avoid relying on that feature?
1245 A: Try to avoid it. Although there would be a emulation for registry in
1246 Mono too. GNOME does have a registry like mechanism for configuration. But
1247 Even if gnome has a configuration system similar to the registry, the keys
1248 will not be equal, so you will probably end up having to do some runtime
1249 detection, and depending on this load an assembly that has your
1250 platform-specific hacks.
1252 Q: System.Data.SqlClient with FreeTDS, will you port parts of these to C# and
1255 A: This has been done.
1260 Q: Are you working on a GCC front-end to C#? A GCC back-end that will
1261 generate CIL images?
1263 A: We would love to see a GCC modification that would generate CIL
1264 images, but there is nothing at this point.
1266 Q: What about making a front-end to GCC that takes CIL images and
1267 generates native code?
1269 A: There is no active work on this area, but Mono already provides
1270 pre-compilation services (Ahead-of-Time compilation).
1272 Q: But would this work around the GPL in the GCC compiler and allow
1273 people to work on non-free front-ends?
1275 A: People can already do this by targeting the JVM byte codes (there
1276 are about 130 compilers for various languages that target the JVM).
1278 <a name="performance"></a>
1281 Q: How fast will Mono be?
1283 A: We can not predict the future, but a conservative estimate is that
1284 it would be at least `as fast as other JIT engines'.
1286 Mono's JIT engine has been recently re-architected, and it provides
1287 many new features, and layers suitable for optimization. It is
1288 relatively easy to add new optimizations to Mono.
1290 The CIL has some advantages over the Java byte code: it is really
1291 an intermediate representation and there are a number of
1292 restrictions on how you can emit CIL code that simplify creating
1295 For example, on the CIL, the stack is not really an abstraction
1296 available for the code generator to use at will. Rather, it is a
1297 way of creating a postfix representation of the parsed tree. At
1298 any given call point or return point, the contents of the stack are
1299 expected to contain the same object types independently of how the
1300 instruction was reached.
1302 <a name="licensing"></a>
1305 Q: Will I be able to write proprietary applications that run with
1308 A: Yes. The licensing scheme is planned to allow proprietary
1309 developers to write applications with Mono.
1311 Q: What license or licenses are you using for the Mono Project?
1313 A: The C# Compiler is released under the terms of the <a
1314 href="http://www.opensource.org/licenses/gpl-license.html">GNU GPL</a>. The runtime
1315 libraries are under the <a
1316 href="http://www.opensource.org/licenses/lgpl-license.html">GNU
1317 Library GPL</a>. And the class libraries are released
1318 under the terms of the <a
1319 href="http://www.opensource.org/licenses/mit-license.html">MIT X11</a>
1322 The Mono runtime and the Mono C# Compiler are also available under
1323 a proprietary license for those who can not use the LGPL and the
1326 For licensing details, contact <a
1327 href="mailto:mono-licensing@ximian.com">mono-licensing@ximian.com</a>
1330 Q: I would like to contribute code to Mono under a particular
1331 license. What licenses will you accept?
1333 A: We will have to evaluate the licenses for compatibility first,
1334 but as a general rule, we will accept the code under the same
1335 terms of the "container" module.
1337 <a name="patents"></a>
1340 Q: Could patents be used to completely disable Mono (either submarine
1341 patents filed now, or changes made by Microsoft specifically to
1342 create patent problems)?
1344 A: First some background information.
1346 The .NET Framework is divided in two parts: the ECMA/ISO covered
1347 technologies and the other technologies developed on top of it like
1348 ADO.NET, ASP.NET and Windows.Forms.
1350 Mono implements the ECMA/ISO covered parts, as well as being a
1351 project that aims to implement the higher level blocks like
1352 ASP.NET, ADO.NET and Windows.Forms.
1354 The Mono project has gone beyond both of those components and has
1355 developed and integrated third party class libraries, the most
1356 important being: Debugging APIs, integration with the Gnome
1357 platform (Accessibility, Pango rendering, Gdk/Gtk, Glade, GnomeUI),
1358 Mozilla, OpenGL, extensive database support (Microsoft only
1359 supports a couple of providers out of the box, while Mono has
1360 support for 11 different providers), our POSIX integration
1361 libraries and finally the embedded API (used to add scripting to
1362 applications and host the CLI, or for example as an embedded
1365 The core of the .NET Framework, and what has been patented by
1366 Microsoft falls under the ECMA/ISO submission. Jim Miller at
1367 Microsoft has made a statement on the patents covering ISO/ECMA,
1368 (he is one of the inventors listed in the patent): <a
1369 href="https://mailserver.di.unipi.it/pipermail/dotnet-sscli/msg00218.html">here</a>.
1371 Basically a grant is given to anyone who want to implement those
1372 components for free and for any purpose.
1374 The controversial elements are the ASP.NET, ADO.NET and
1375 Windows.Forms subsets. Those are convenient for people who need
1376 full compatibility with the Windows platform, but are not required
1377 for the open source Mono platform, nor integration with today's
1378 Mono's rich support of Linux.
1380 The Mono strategy for dealing with these technologies is as
1381 follows: (1) work around the patent by using a different
1382 implementation technique that retains the API, but changes the
1383 mechanism; if that is not possible, we would (2) remove the pieces
1384 of code that were covered by those patents, and also (3) find prior
1385 art that would render the patent useless.
1387 Not providing a patented capability would weaken the
1388 interoperability, but it would still provide the free software /
1389 open source software community with good development tools, which
1390 is the primary reason for developing Mono.
1392 The patents do not apply in countries where software patents are
1395 For Linux server and desktop development, we only need the ECMA
1396 components, and things that we have developed (like Gtk#) or Apache
1399 Q: Is Mono only an implementation of the .NET Framework?
1401 A: Mono implements both the .NET Framework, as well as plenty of class
1402 libraries that are either Unix specific, <a
1403 href="http://www.gnome.org">Gnome</a> specific, or that are not
1404 part of the .NET Framework but people find useful.
1406 The following map shows the relationship between the components:
1408 <img src="http://primates.ximian.com/~miguel/tmp/map.png">
1411 ** Miscellaneous Questions
1413 Q: You say that the CLI allows multiple languages to execute on the
1414 same environment. Isn't this the purpose of CORBA?
1416 A: The key difference between CORBA (and COM) and the CLI is that the
1417 CLI allows "data-level interoperability" because every
1418 language/component uses the same data layout and memory management.
1420 This means you can operate directly upon the data types that someone
1421 else provides, without having to go via their interfaces. It also
1422 means you don't have to "marshal" (convert) parameters (data
1423 layouts are the same, so you can just pass components directly) and
1424 you don't have to worry about memory management, because all
1425 languages/components share the same garbage collector and address
1426 space. This means much less copying and no need for reference
1429 Q: Will you support COM?
1431 A: The runtime will support XPCOM on Unix systems and COM on Windows.
1432 Most of the code for dynamic trampolines exists already.
1434 Q: Will Ximian offer certifications on Mono or related technologies?.
1436 A: It's possible. But there is no plan about this. So the short answer is no.
1438 Q: How can I report a bug?
1440 A: The best thing is to track down the bug and provide a simple test
1441 to reproduce the bug. You can then add the bug to our bug tracking
1442 system. You can use our <a href="bugs.html">Bug Form</a> to enter
1443 bugs for the appropriate component.
1445 Please provide information about what version of mono you're using
1446 and any relevant details to be able to reproduce the bug. Note that
1447 bugs reported on the mailing-list may be easily forgotten, so it's
1448 better to file them in the <a href="http://bugzilla.ximian.com/enter_bug.cgi">bug tracking system</a>.
1450 Q: Does mcs support the same command line options as the MS C#
1453 A: The Mono C# compiler now supports the same command line
1454 arguments as the Microsoft C# compiler does.
1456 Q: How about getting searchable archives on lists.ximian.com?
1458 A: You can perform a search on the mono-related mailing lists
1459 <a href="http://www.go-mono.com/mailing-lists.html">here</a>.
1461 Q: When using mono from cvs or from a snapshot, I get an error messaage
1462 saying that Mono and the runtime are out of sync. How do I fix that?
1464 A: If you use mono from cvs, you need to be prepared for changes in the
1465 runtime internals. This means that you should keep a working setup
1466 before blindling updating (a working setup may just be the last released
1467 tarball or a recent binary snapshot).
1468 Usually, compiling corlib with mcs before recompiling the C runtime does
1469 the right thing (but occasionally you may need to do it the other
1472 Q: Why are you going for a GtkHtml implementation?
1474 A: GtkHTML is just a lightweight HTML rendering engine that does not
1475 support CSS, so we need it to look decent for those of us that will
1476 be using the documentation in our day-to-day work on Linux. The
1477 Web-based interfaces lack the agility that you get from a native GUI
1478 tool to browse your documentation. Probably later on, we will write
1479 scripts and generate a full documentation set that is web-browsable,
1480 but we need a command-line and GUI tools that we can use natively on
1481 Linux when disconnected from the Web (and that has better
1482 interactions than a web page).
1484 Q: Is there a command-line tool that allows me to access .NET interactively?
1486 A: There are several but one that is free software and uses MCS is the one
1487 Dennis Lu from Rice University is working on; a REPL C# interpreter.
1489 Q: Is it possible to use Visual C++ with Mono?.
1491 A: It's possible to run VC++ generated apps under Mono, but we do not
1492 provide a Manager C++ compiler ourselves.
1494 Q: Does Mono support generics?.
1496 A: Mono doesn't support generics currently but a lot of work is being
1499 <a name="problems"></a>
1500 ** Mono Common Problems
1502 If you are having problems compiling or running Mono software
1503 or if you think that you found a bug, etc. Please visit the
1504 <a href="http://monoevo.sf.net/mono-common-problems.html">Mono Common Problems</a> document and try there.
1508 The FAQ contains material contributed by Miguel de Icaza, Jaime Anguiano, Lluis Sánchez.