Running Mono

Running Mono Hinne Hettema

h.hettema@auckland.ac.nz

Jaime Anguiano Olarra

jaime@genuara.ugr.es

2002-06 0.1 2002-06-20 HH First release This document describes how to install mono on your Linux system from the source and describes some simple experiments you can perform with this installation. Introduction Mono is an open source implementation of the Common Language Infrastructure (CLI) specified in ECMA standard 335. It comes with a C# compiler and provides an extensible platform to develop and run applications that are interoperable with Microsoft .NET. Mono is not finished--it is a project still under development. As a result, installation and configuration may not be as smooth as you will be used to from other Linux applications. Nevertheless, mono is in a state that will allow you to get it up and running and gain experience with it--which is, I would suggest, a very smart thing to do. This document is limited in the following sense: it describes how to download a 'stable' version of mono as a 'tarball' and get it to run on your computer. I'm also assuming you run mono on Linux rather than on Windows. All the examples have been tested on a 'vanilla' Red Hat 7.3 installation. There are two items this document will not cover: the first is how to self host the mcs compiler under linux and the second is the graphical user environment which is implemented as GTK#. These two interesting topics are the subject of two more howto's that I'm planning. This document is also less useful for two types of people. If you are a very inexperienced linux user and want to know what mono is all about, there is an easier way to install mono. Go to mono.baselabs.org and download the rpm's ready for installation on your system. This site also runs a tutorial that is worth reading. If you are a very experienced user wanting to contribute to the mono code, you should probably regularly do a CVS download. At the moment, the mono code grows very fast, and the 'stable' releases still appear too slowly. This document is aimed at the mono beginner, and aims to present a complete view of a minimal installation, which will allow you to experiment with mono to some degree. It also describes some of those experiments. We expect that after reading this document you'll go on to do either of two things: Continue to contribute to the mono project in some shape or form. The website has some ideas and suggestions under the heading 'Contributing'. Continue to write applications that run in mono. We hope this document will be useful to you in your first steps with mono. Happy hacking! A note on the development of this document This document is expected to grow into a full 'running mono howto' over time. As of yet, it does not really discuss some of the excellent efforts of others to package mono into an rpm or deb and prepare it for easy installation. It is our aim to include this in future versions of this document. Prerequisites This document assumes you are somewhat familiar with the architecture of the Common Language Infrastructure and the C# programming language. To compile mono on your system, you will also have to satisfy some dependencies on other software. A list of these are given on the mono download page. Read through this list to see if you've got all components. On a practical note, I had no dependency issues with the installation of mono 0.12 on a 'standard issue' Red Hat 7.3 build. Disclaimer No liability for the contents of this document can be accepted. Use the concepts, examples and information at your own risk. There may be errors and inaccuracies, that could be damaging to your system. Proceed with caution, and although this is highly unlikely, the author(s) do not take any responsibility. All copyrights are held by their by their respective owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Naming of particular products or brands should not be seen as endorsements. Credits / Contributors This document was originally created by Jaime Anguiano Olarra, but has been extensively rewritten. Credits are due to Jaime Anguiano Olarra jaime@geneura.ugr.es for creating the original version of this document, and in fact the document that got me through installing mono for the first time. My partner Margaret for support on my more exotic ventures. Feedback Feedback is most certainly welcome for this document. Send your additions, comments and criticisms to the following email address: mono-docs-list@ximian.com. I am lurking on this list and will maintain this document as required. Installing Mono Obtaining Mono There are several ways to get Mono running on your computer. This document will discuss only one of those: downloading the source tarball and utilising the make utilities to get mono up and running. There is only one mono package to worry about if you are just after a 'base' install of mono: the mono runtime. This package, found under the name "mono-x.xx" has got a compiled version of the compiler built in. You'll be able to complete everything in this document if you just install the runtime, but taking a look at the compiler package is well worth the effort. The compiler is written in C# and is 'self hosting' which means it is able to compile itself. As of this moment, it is my understanding that there are still some issues with the 'self hosting' bit of the compiler on linux, although this is expected to work in later versions of mono. If you are just interested in finding out how mono will work under linux, I would not worry about the self-hosting bit for now. The self-hosting of the compiler will be the topic of a future howto. See the mono download site for the source of the tarballs. This page also lists the current versions of the software mono depends on. Make sure that your system has all the required versions, otherwise mono won't compile. At a minimum for mono 0.12, you'll need to: download and install pkg-config. download and install glib 1.3. Installing the tarballs is done via GNU autoconf and automake. The general upshot of running autoconf and automake is that you can type ./configure and then make to do the build. Typing make install completes the installation of mono on your system. To build the mono runtime package, unzip the tarball to some useful location. I tend to use /usr/src as the location, but you could really do it anywhere. For the install process, it is also a good idea to be 'root'. The installation process will shuttle some executables into /usr/local/bin (more about that later). Unzipping the tarballs will have created two directories in /usr/src/, one called something like mono-x.xx and the other mcs-x.xx. The one called 'mono' is the runtime environment, and this contains all that is initially needed to run mono and investigate its inner workings. To start building the mono runtime, first type ./configure. You will see an output like this: [root@taurus mono-0.12]# ./configure loading cache ./config.cache checking host system type... i686-pc-linux-gnu checking target system type... i686-pc-linux-gnu checking build system type... i686-pc-linux-gnu checking for a BSD compatible install... (cached) /usr/bin/install -c checking whether build environment is sane... yes checking whether make sets ${MAKE}... (cached) yes checking for working aclocal... found snip .... checking BASE_DEPENDENCIES_CFLAGS... -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include checking BASE_DEPENDENCIES_LIBS... -lglib-2.0 checking for GC_malloc in -lgc... (cached) no configure: warning: Compiling mono without GC. checking if off_t is 64 bits wide... no checking if _FILE_OFFSET_BITS=64 gives 64 bit off_t... ok snip ... creating Makefile creating mono/Makefile creating mono/utils/Makefile creating mono/metadata/Makefile creating mono/dis/Makefile creating mono/cil/Makefile creating mono/arch/Makefile creating mono/os/Makefile creating mono/os/win32/Makefile creating mono/os/unix/Makefile creating mono/arch/x86/Makefile creating mono/arch/ppc/Makefile creating mono/arch/sparc/Makefile creating mono/arch/arm/Makefile creating mono/interpreter/Makefile creating mono/tests/Makefile creating mono/benchmark/Makefile creating mono/monoburg/Makefile creating mono/monograph/Makefile creating mono/jit/Makefile creating mono/io-layer/Makefile creating mono/handles/Makefile creating runtime/Makefile creating scripts/Makefile creating man/Makefile creating doc/Makefile creating docs/Makefile creating config.h config.h is unchanged GC: auto [root@taurus mono-0.12]# This means that the configure script has now created all the makefiles necessary to complete the build on your system. Note the "GC: auto" at the end of the list of commands. GC stands for "garbage collection" and it will be addressed in a later section of this document. You are now ready to start the mono "build" process. To kick this off, you can type make at the command prompt. You'll see something like this: [root@taurus mono-0.12]# make make all-recursive make[1]: Entering directory `/usr/src/mono-0.12' Making all in mono make[2]: Entering directory `/usr/src/mono-0.12/mono' Making all in utils make[3]: Entering directory `/usr/src/mono-0.12/mono/utils' gcc -DHAVE_CONFIG_H -I. -I. -I../.. -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I../.. -I../../mono -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -g -Wall -Wunused -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wno-cast-qual -Wcast-align -Wwrite-strings -c mono-hash.c and this will continue for a while. On my 1 GHz Duron with 256 MB of RAM the total build process takes about three minutes. All the terrible flags after gcc have essentially been set by the configure script and there is no need to worry about these. To finally install mono, you can type make install to get a working version of mono. This command will copy the scripts that run the executables to a place where the operating system will be ale to find them. This location is /usr/local/bin on my system. Garbage Collection To make the mint interpreter work with garbage collection, you first need to install a garbage collection package on your system. Mono works with Boehm Garbage collection, which is found at http://www.hpl.hp.com/personal/Hans_Boehm/gc/ . To get garbage collection to work, I downloaded the source tarball into /usr/src/ and typed ./configure followed by make and make install. There is one glitch to work around. The header file for the garbage collection gc.h is found in the /usr/src/gc6.0/include directory (at least on my system). The mono build process will break on this location: it is looking for the header file in some other place called /usr/include/gc/ and won't be able to find the correct header file. The solution is to build a symbolic link between these two locations as follows [root@taurus include]# ln -s /usr/src/gc6.0/include/ /usr/include/gc after which you'll be able to list the directory contents as if they were in /usr/include [root@taurus include]# pwd /usr/include [root@taurus include]# ls /usr/include/gc cord.h gc_backptr.h gc_inline.h javaxfc.h ec.h gc_cpp.h gc_local_alloc.h leak_detector.h gc gc_gcj.h gc_mark.h new_gc_alloc.h gc_alloc.h gc.h gc_pthread_redirects.h private gc_amiga_redirects.h gc_inl.h gc_typed.h weakpointer.h [root@taurus include]# To get mono to work with garbage collection, you'll have to rebuild the environment. This is done easily by typing make distclean to clean up any existing executables. Continue the build by typing ./configure, and look at the last line. It should read: snip... creating config.h GC: boehm [root@taurus mono-0.12]# The GC: boehm tells you that garbage collection has been turned on. Now to compile the runtime, you type make and make install as previously. You now have mono working with Garbage Collection. Although my experimentation is incomplete as of this time, I have found some issues with running Garbage Collection continuously, and my recommendation would be to turn it off for now. To turn garbage collection off again, you have to go to the /usr/src directory where you extracted the tarball. Enter the gc6.0 directory and type make uninstall to uninstall Garbage Collection. Then in your mono directory, type make distclean followed by ./configure, make and make install. Running mono Basic steps To work with mono, you first have to create a C# program. Open up your favourite editor, and type in the following code: using System; class Hello { public static void Main(String[] args) { Console.WriteLine("mono:: is alive and well..."); for (int i = 0; i < args.Length; i++) Console.WriteLine("Argument {0} = {1}", i, args[i]); } } Save the file as hello.cs. To compile this into a working program, type mcs hello.cs. If you get the following: [hinne@taurus hello]$ mcs hello.cs RESULT: 0 [hinne@taurus hello]$ you know the compile worked fine. If you see some strange error messages including the word 'parser' somewhere, you made a mistake in your program. Fix this up first. You are now ready to execute your first mono program. To execute the code, type [hinne@taurus hello]$ mono hello.exe arg1 arg2 arg 3 (where we have given some arguments just for fun) and you'll see the following: mono:: is alive and well... Argument 0 = arg1 Argument 1 = arg2 Argument 2 = arg Argument 3 = 3 RESULT: 0 As you can see, mono printed the line "mono:: is alive and well" and printed the list of arguments. This completes the creation and execution of your first mono program. Interpreter But mono will allow you to do more. First of all, mono is the compiled mono execution environment which uses the Just in Time (JIT) compiler. Mono also comes with an interpreted environment, which can be accessed using the command 'mint' as follows [hinne@taurus hello]$ mint hello.exe arg1 arg 2 mono:: is alive and well... Argument 0 = arg1 Argument 1 = arg Argument 2 = 2 [hinne@taurus hello]$ As you can see, it makes no difference to mono output which environment you use, but what happens under the hood is very different. If you use 'mono' as the command line tool, you call the 'production' execution environment which will read your portable executable (PE) file, and call the just in time (JIT) compiler to compile the PE code down to machine level code (in my case, an x86 architecture) after which it is executed. If you use mint, the JIT is not used, and the PE code is interpreted into x86 instructions for execution. In fact, for our simple 'hello' mint is slightly faster. The point is that the JIT compiler will take some time to compile the code of our program and store it in some location in memory, but the subsequent execution of the code is faster with mono. You can see what happens below (the thing to look for is the 'user' time: 0.1 seconds with mono and 0.06 seconds with mint): [hinne@taurus hello]$ time mono hello.exe arg1 arg 2 mono:: is alive and well... Argument 0 = arg1 Argument 1 = arg Argument 2 = 2 RESULT: 0 real 0m0.575s user 0m0.100s sys 0m0.010s [hinne@taurus hello]$ time mint hello.exe arg1 arg 2 mono:: is alive and well... Argument 0 = arg1 Argument 1 = arg Argument 2 = 2 real 0m0.545s user 0m0.060s sys 0m0.000s [hinne@taurus hello]$ After this simple run of mono, it is time to play with some options. I won't cover these in detail since there are quite a few, and also because I assume you downloaded mono to hack it around in the first place. So I'll leave some pointers. Debugging Mono supports a debugging option when you specify the "-d" flag while running the runtime. Utilising this flag will get you a significant amount of output, and it may be an idea to specify an output file as well. The interesting aspect of this file is that it allows you to see to some extent (quite precisely, actually) what the JIT compiler is up to. Statistics It is also possible to collect some runtime statistics on your program. These will give you some idea of the resource utilisation of your program. [hinne@taurus hello]$ mono --stats hello.exe mono:: is alive and well... RESULT: 0 Mono Jit statistics Compiled methods: 58 Methods cache lookup: 15 Method trampolines: 698 Basic blocks: 188 Max basic blocks: 15 Allocated vars: 238 Analyze stack repeat: 61 Compiled CIL code size: 2450 Native code size: 10167 Max code size ratio: 7.13 (FileStream::FlushBuffer) Biggest method: 1016 (StreamWriter::Write) Code reallocs: 27 Allocated code size: 22073 Inlineable methods: 17 Inlined methods: 22 Created object count: 18 Initialized classes: 127 Used classes: 37 Static data size: 288 VTable data size: 8292 Inspecting IL Assembly code Mono also provides a small tool that will let you disassemble the executable (.exe) file so you can have a peek under the hood. This tool is monodis, and is run as follows: [hinne@taurus hello]$ monodis hello.exe .assembly extern mscorlib { .ver 0:0:0:0 } .assembly 'hello' { .hash algorithm 0x00008004 .ver 0:0:0:0 } .class private auto ansi beforefieldinit Hello extends [mscorlib]System.Object { // method line 1 .method public hidebysig specialname rtspecialname instance default void .ctor() cil managed { // Method begins at RVA 0x20ec // Code size 7 (0x7) .maxstack 8 IL_0000: ldarg.0 IL_0001: call instance void System.Object::.ctor() IL_0006: ret } // end of method instance default void .ctor() // method line 2 .method public static default void Main(string[] args) cil managed { // Method begins at RVA 0x20f4 .entrypoint // Code size 56 (0x38) .maxstack 5 .locals init ( int32 V_0, int32 V_1) IL_0000: ldstr "mono:: is alive and well..." IL_0005: call void System.Console::WriteLine(string) IL_000a: ldc.i4.0 IL_000b: stloc.0 IL_000c: ldloc.0 IL_000d: ldarg.s 0 IL_000f: ldlen IL_0010: clt IL_0012: brfalse IL_0037 IL_0017: ldstr "Argument {0} = {1}" IL_001c: ldloc.0 IL_001d: box [mscorlib]System.Int32 IL_0022: ldarg.s 0 IL_0024: ldloc.0 IL_0025: ldelem.ref IL_0026: call void System.Console::WriteLine(string, object, object) IL_002b: nop IL_002c: ldloc.0 IL_002d: ldc.i4.1 IL_002e: add IL_002f: stloc.1 IL_0030: ldloc.1 IL_0031: stloc.0 IL_0032: br IL_000c IL_0037: ret } // end of method default void Main(string[] args) } // end of type Hello [hinne@taurus hello]$ This is the listing of the code of your program in a language called IL assembly, or Common Intermediate Language (CIL). The CIL provides the portability of the mono platform, and ensures that code compiled with Microsoft's .NET framework will work on mono and vice versa. Man pages Mono has man pages already installed, and generally, typing man before the command you wish to execute should help in getting a list of the options. In many cases, it's still up to you to figure out what they do. Problems With mono being as new as it is, it is likely that you will have some problems with installation. The following are some ideas to help you out in a bind: See the Ximian Bugzilla page to find out if there is a bug report about your specific issue. Read this document. If it does not solve your problem, we want to know about it. Please send a message to the email address listed for feedback at the beginning of the document. Visit the mono mailing lists' archives and do a little research in there for threads talking about the problem you have. If you still cannot correct the problem, send a message to the mono list. When you do this, please be as precise as possible--i.e. mention the system you are running, the version of mono that you have the problem with, and give any error codes and other output that might appear. Known Problems mcs fails to compile in Linux. To the best of my knowledge, as of yet mcs cannot compile in Linux. Try to install the already made packages from http://mono.baselabs.org/index.php/software. Copyright and License This document, Running mono, is copyrighted (c) 2002 by Hinne Hettema and Jaime Anguiano Olarra. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". GNU Free Documentation License Version 1.1, March 2000

Copyright (C) 2000 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

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