1mcs(1) General Commands Manual mcs(1)
2
6 mcs - Turbo C# Compiler
7
9 mcs [option] [source-files]
10
12 mcs is the Turbo C# compiler (also known as the Mono C# compiler), it
13 is an implementation of the ECMA-334 language specification. You can
14 pass one or more options to drive the compiler, and a set of source
15 files. Extra options or arguments can be provided in a response file.
16 Response files are referenced by prepending the @ symbol to the
17 response file name.
18 The mcs compiler is used to compile against the latest Mono Base Class
20 Library version and fully implements C# 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0
21 specifications with partial support for C# 7.0.
22 See the section on packages for more information.
24 The Turbo C# compiler accepts the same command line options that the
26 Microsoft C# compiler does. Those options can start with a slash or a
27 dash (/checked is the same as -checked). Additionally some GNU-like
28 options are supported, those begin with "--". All MCS-specific flags
29 which are not available in the Microsoft C# compiler are available only
30 with the GNU-style options.
31 C# source files must end with a ".cs" extension. Compilation of C#
33 source code requires all the files that make up a library, module or
34 executable to be provided on the command line. There is no support for
35 partial compilation. To achieve the benefits of partial compilation,
36 you should compile programs into their own assemblies, and later refer‐
37 ence them with the "-r" flag.
38 The Turbo C# compiler generates images (.exe files) that contain CIL
40 byte code that can be executed by any system that implements a Common
41 Language Infrastructure virtual machine such as the Microsoft .NET run‐
42 time engine on Windows or the Mono runtime engine on Unix systems.
43 Executables are not bound to a specific CPU or operating system.
44 The Turbo C# compiler by default only references three assemblies:
46 mscorlib.dll, System.dll and System.Xml.dll. If you want to reference
47 extra libraries you must manually specify them using the -pkg: command
48 line option or the -r: command line option. Alternatively if you want
49 to get all of the System libraries, you can use the -pkg:dotnet command
50 line option.
51
53 --about
54 Displays information about the Turbo C# compiler
55 --addmodule:MODULE1[,MODULE2]
57 Includes the specified modules in the resulting assembly. Mod‐
58 ules are created by calling the compiler with the -target:module
59 option
60 -checked, -checked+
62 Sets the default compilation mode to `checked'. This makes all
63 the math operations checked (the default is unchecked).
64 -checked-
66 Sets the default compilation mode to `unchecked'. This makes
67 all the math operations unchecked (this is the default).
68 -clscheck-, -clscheck+
70 Disables or enables the Common Language Specification (CLS)
71 checks (it is enabled by default).
72 The Common Language Specification (CLS) defines an interoperable
74 subset of types as well as conventions that compilers (CLS pro‐
75 ducers) and developers must follow to expose code to other pro‐
76 gramming languages (CLS consumers).
77 -codepage:ID
79 Specifies the code page used to process the input files from the
80 point it is specified on. By default files will be processed in
81 the environment-dependent native code page. The compiler will
82 also automatically detect Unicode files that have an embedded
83 byte mark at the beginning.
84 Other popular encodings are 28591 (Latin1), 1252 (iso-8859-1)
86 and 65001 (UTF-8).
87 MCS supports a couple of shorthands: "utf8" can be used to spec‐
89 ify utf-8 instead of using the cryptic 65001 and "reset"
90 restores the automatic handling of code pages. These shorthands
91 are not available on the Microsoft compiler.
92 -define:SYMLIST, -d:SYMLIST
94 Defines the symbol listed by the semi-colon separated list SYM‐
95 LIST SYMBOL. This can be tested in the source code by the pre-
96 processor, or can be used by methods that have been tagged with
97 the Conditional attribute.
98 -debug, -debug+
100 Generate debugging information. To obtain stack traces with
101 debugging information, you need to invoke the mono runtime with
102 the `--debug' flag. The debugging information is stored in a MDB
103 file located in same output folder as produced assembly.
104 -debug-
106 Do not generate debugging information.
107 -delaysign+
109 Only embed the strongname public key into the assembly. The
110 actual signing must be done in a later stage using the SN tool.
111 This is useful to protect the private key during development.
112 Note that delay signing can only be done using a strongname key
113 file (not a key container). The option is equivalent to includ‐
114 ing [assembly: AssemblyDelaySign (true)] in your source code.
115 Compiler option takes precedence over the attributes.
116 -delaysign-
118 Default. Strongname (sign) the assembly using the strong name
119 key file (or container). The option is equivalent to including
120 [assembly: AssemblyDelaySign (false)] in your source code. Com‐
121 piler option takes precedence over the attributes.
122 -doc:FILE
124 Extracts the C#/XML documentation from the source code and
125 stores in in the given FILE.
126 -errorreport
128 This flag is ignored by Mono's C# compiler and is present only
129 to allow MCS to be used as a CSC replacement for msbuild/xbuild.
130 --fatal
132 This is used for debugging the compiler. This makes the error
133 emission generate an exception that can be caught by a debugger.
134 -filealign
136 This flag is ignored by Mono's C# compiler and is present only
137 to allow MCS to be used as a CSC replacement for msbuild/xbuild.
138 -fullpaths
140 Any source code error or warning issued by the compiler includes
141 file name only by default. This option causes compiler to issue
142 absolute file path instead.
143 -keyfile:KEYFILE
145 Strongname (sign) the output assembly using the key pair present
146 in the specified strong name key file (snk). A full key pair is
147 required by default (or when using delaysign-). A file contain‐
148 ing only the public key can be used with delaysign+. The option
149 is equivalent to including [assembly: AssemblyKeyFile ("KEY‐
150 FILE")] in your source code. Compiler option takes precedence
151 over the attributes.
152 -keycontainer:CONTAINER
154 Strongname (sign) the output assembly using the key pair present
155 in the specified container. Note that delaysign+ is ignored when
156 using key containers. The option is equivalent to including
157 [assembly: AssemblyKeyName ("CONTAINER")] in your source code.
158 Compiler option takes precedence over the attributes.
159 -langversion:TEXT
161 The option specifies the version of the language to use. The
162 feature set is different in each C# version. This switch can be
163 used to force the compiler to allow only a subset of the fea‐
164 tures. The possible values are:
165 Default
167 Instruct compiler to use the latest version. Equivalent
168 is to omit the switch (this currently defaults to the C#
169 6.0 language specification).
170 ISO-1 Restrict compiler to use only first ISO standardized fea‐
172 tures. The usage of features such as generics, static
173 classes, anonymous methods will lead to error.
174 ISO-2 Restrict compiler to use only the second ISO standardized
176 features. This allows the use of generics, static
177 classes, iterators and anonymous methods for example.
178 3 Restrict the compiler to use only the features available
180 in C# 3.0 (a superset of ISO-1 and ISO-2).
181 4 Restrict the compiler to use only the features available
183 in C# 4.0 specification.
184 5 Restrict the compiler to use only the features available
186 in C# 5.0 specification.
187 6 Restrict the compiler to use only the features available
189 in C# 6.0 specification.
190 experimental
192 Enables unstable features from upcoming versions of the
193 language.
194 Notice that this flag only restricts the language features
196 available to the programmer. A version of produced assemblies
197 can be controlled using SDK option.
198 -lib:PATHLIST
200 Each path specified in the comma-separated list will direct the
201 compiler to look for libraries in that specified path.
202 -L PATH
204 Directs the compiler to look for libraries in the specified
205 path. Multiple paths can be provided by using the option multi‐
206 ple times.
207 -main:CLASS
209 Tells the compiler which CLASS contains the entry point. Useful
210 when you are compiling several classes with a Main method.
211 -nostdlib, -nostdlib+
213 Use this flag if you want to compile the core library. This
214 makes the compiler load its internal types from the assembly
215 being compiled.
216 -noconfig, -noconfig+
218 Disables the default compiler configuration to be loaded. The
219 compiler by default has references to the system assemblies.
220 -nowarn:WARNLIST
222 Makes the compiler ignore warnings specified in the comma-sepa‐
223 rated list WARNLIST>
224 -optimize, -optimize+, -optimize-
226 Controls compiler code generation optimizations on the code.
227 Using -optimize or -optimize+ will turn on optimizations, -opti‐
228 mize- will turn it off. The default in mcs is to optimize-. The
229 option can be mixed with -debug but for the best debugging expe‐
230 rience it is recommended leave the options off.
231 -out:FNAME, -o FNAME
233 Names the output file to be generated.
234 --parse
236 Used for benchmarking. The compiler will only parse its input
237 files.
238 -pathmap:K=V[,Kn=Vn]
240 Sets a mapping for source path names used in generated output.
241 -pkg:package1[,packageN]
243 Reference assemblies for the given packages.
244 The compiler will invoke pkg-config --libs on the set of pack‐
246 ages specified on the command line to obtain libraries and
247 directories to compile the code.
248 This is typically used with third party components, like this:
250 $ mcs -pkg:gtk-sharp demo.cs
252 -pkg:dotnet
254 This will instruct the compiler to reference the System.*
255 libraries available on a typical dotnet framework instal‐
256 lation, notice that this does not include all of the Mono
257 libraries, only the System.* ones. This is a convenient
258 shortcut for those porting code.
259 -platform:ARCH
261 Used to specify the target platform. The possible values are:
262 anycpu, anycpu32bitpreferred, arm, x86, x64 or itanium. The
263 default option is anycpu.
264 -resource:RESOURCE[,ID]
266 Embeds to the given resource file. The optional ID can be used
267 to give a different name to the resource. If not specified, the
268 resource name will be the file name.
269 -linkresource:RESOURCE[,ID]
271 Links to the specified RESOURCE. The optional ID can be used to
272 give a name to the linked resource.
273 -r:ASSEMBLY1[,ASSEMBLY2], -reference ASSEMBLY1[,ASSEMBLY2]
275 Reference the named assemblies. Use this to use classes from
276 the named assembly in your program. The assembly will be loaded
277 from either the system directory where all the assemblies live,
278 or from the path explicitly given with the -L option.
279 You can also use a semicolon to separate the assemblies instead
281 of a comma.
282 -reference:ALIAS=ASSEMBLY
284 Extern alias reference support for C#.
285 If you have different assemblies that provide the same types,
287 the extern alias support allows you to provide names that your
288 software can use to tell those appart. The types from ASSEM‐
289 BLY will be exposed as ALIAS, then on the C# source code, you
290 need to do:
291 extern alias ALIAS;
293 To bring it into your namespace. For example, to cope with two
294 graphics libraries that define "Graphics.Point", one in
295 "OpenGL.dll" and one in "Postscript.dll", you would invoke the
296 compiler like this:
297 mcs -r:Postscript=Postscript.dll -r:OpenGL=OpenGL.dll
299 And in your source code, you would write:
301 extern alias Postscript;
303 extern alias OpenGL;
304 class X {
306 // This is a Graphics.Point from Postscrip.dll
307 Postscript.Point p = new Postscript.Point ();
308 // This is a Graphics.Point from OpenGL.dll
310 OpenGL.Point p = new OpenGL.Point ();
311 }
312 -recurse:PATTERN, --recurse PATTERN
314 Does recursive compilation using the specified pattern. In Unix
315 the shell will perform globbing, so you might want to use it
316 like this:
317 $ mcs -recurse:'*.cs'
319 -sdk:VERSION
321 Used to specify the version of Base Class Library assemblies
322 used for compilation. Following predefined values are valid: 2,
323 4 (default) as well as any custom value. The predefined version
324 number means which custom value is specified mcs will try to
325 find Base Class Libraries in the mono installed location PRE‐
326 FIX/lib/mono/<value>.
327 --shell
329 Starts up the compiler in interactive mode, providing a C# shell
330 for statements and expressions. A shortcut is to use the
331 csharp command directly.
332 --stacktrace
334 Generates a stack trace at the time the error is reported, use‐
335 ful for debugging the compiler.
336 -target:KIND, -t:KIND
338 Used to specify the desired target. The possible values are:
339 exe (plain executable), winexe (Windows.Forms executable),
340 library (component libraries) and module (partial library).
341 --timestamp
343 Another debugging flag. Used to display the times at various
344 points in the compilation process.
345 -unsafe, -unsafe+
347 Enables compilation of unsafe code.
348 -v Debugging. Turns on verbose yacc parsing.
350 --version
352 Shows the compiler version.
353 -warnaserror, -warnaserror+
355 All compilers warnings will be reported as errors.
356 -warnaserror:W1,[Wn], -warnaserror+:W1,[Wn]
358 Treats one or more compiler warnings as errors.
359 -warnaserror-:W1,[Wn]
361 Sets one or more compiler warnings to be always threated as
362 warnings. Becomes useful when used together with -warnaserror.
363 -warn:LEVEL
365 Sets the warning level. 0 is the lowest warning level, and 4 is
366 the highest. The default is 4.
367 -win32res:FILE
369 Specifies a Win32 resource file (.res) to be bundled into the
370 resulting assembly.
371 -win32icon:FILE
373 Attaches the icon specified in FILE on the output into the
374 resulting assembly.
375 -- Use this to stop option parsing, and allow option-looking param‐
377 eters to be passed on the command line.
378
380 When referencing an assembly, if the name of the assembly is a path,
381 the compiler will try to load the assembly specified in the path. If
382 it does not, then the compiler will try loading the assembly from the
383 current directory, the compiler base directory and if the assembly is
384 not found in any of those places in the directories specified as argu‐
385 ments to the -lib: command argument.
386 The compiler uses the library path to locate libraries, and is able to
388 reference libraries from a particular package if that directory is
389 used. To simplify the use of packages, the C# compiler includes the
390 -pkg: command line option that is used to load specific collections of
391 libraries.
392 Libraries visible to the compiler are stored relative to the installa‐
394 tion prefix under PREFIX/lib/mono/ called the PACKAGEBASE and the
395 defaults for mcs, gmcs and smcs are as follows:
396 mcs References the PACKAGEBASE/1.0 directory
398 gmcs References the PACKAGEBASE/2.0 directory
400 smcs References the PACKAGEBASE/2.1 directory
402 Those are the only runtime profiles that exist. Although other direc‐
404 tories exist (like 3.0 and 3.5) those are not really runtime profiles,
405 they are merely placeholders for extra libraries that build on the 2.0
406 foundation.
407 Software providers will distribute software that is installed relative
409 to the PACKAGEBASE directory. This is integrated into the gacutil tool
410 that not only installs public assemblies into the Global Assembly Cache
411 (GAC) but also installs them into the PACKAGEBASE/PKG directory (where
412 PKG is the name passed to the -package flag to gacutil).
413 As a developer, if you want to consume the Gtk# libraries, you would
415 invoke the compiler like this:
416 $ mcs -pkg:gtk-sharp-2.0 main.cs
418 The -pkg: option instructs the compiler to fetch the definitions for
420 gtk-sharp-2.0 from pkg-config, this is equivalent to passing to the C#
421 compiler the output of:
422 $ pkg-config --libs gtk-sharp-2.0
424 Usually this merely references the libraries from PACKAGEBASE/PKG.
426 Although there are directory names for 3.0 and 3.5, that does not mean
428 that there are 3.0 and 3.5 compiler editions or profiles. Those are
429 merely new libraries that must be manually referenced either with the
430 proper -pkg: invocation, or by referencing the libraries directly.
431
433 The TRACE and DEBUG defines have a special meaning to the compiler.
434 By default calls to methods and properties in the System.Diagnos‐
436 tics.Trace class are not generated unless the TRACE symbol is defined
437 (either through a "#define TRACE") in your source code, or by using the
438 --define TRACE in the command line.
439 By default calls to methods and properties in the System.Diagnos‐
441 tics.Debug class are not generated unless the DEBUG symbol is defined
442 (either through a "#define DEBUG") in your source code, or by using the
443 --define DEBUG in the command line.
444 Note that the effect of defining TRACE and DEBUG is a global setting,
446 even if they are only defined in a single file.
447
449 When using the "-debug" flag, MCS will generate a file with the exten‐
450 sion .mdb that contains the debugging information for the generated
451 assembly. This file is consumed by the Mono debugger (mdb).
452
454 MCS_COLORS
455 If this variable is set, it contains a string in the form "fore‐
456 ground,background" that specifies which color to use to display
457 errors on some terminals.
458 The background is optional and defaults to your terminal current
460 background. The possible colors for foreground are: black,
461 red, brightred, green, brightgreen, yellow, brightyellow, blue,
462 brightblue, magenta, brightmagenta, cyan, brightcyan, grey,
463 white and brightwhite.
464 The possible colors for background are: black, red, green, yel‐
466 low, blue, magenta, cyan, grey and white.
467 For example, you could set these variable from your shell:
469 export MCS_COLORS
470 MCS_COLORS=errors=brightwhite,red
471 You can disable the built-in color scheme by setting this vari‐
473 able to "disable".
474
476 During compilation the MCS compiler defines the __MonoCS__ symbol, this
477 can be used by pre-processor instructions to compile Mono C# compiler
478 specific code. Please note that this symbol is only to test for the
479 compiler, and is not useful to distinguish compilation or deployment
480 platforms.
481
483 The Mono C# Compiler was written by Miguel de Icaza, Ravi Pratap, Mar‐
484 tin Baulig, Marek Safar and Raja Harinath. The development was funded
485 by Ximian, Novell and Marek Safar.
486
488 The Mono Compiler Suite is released under the terms of the GNU GPL or
489 the MIT X11. Please read the accompanying `COPYING' file for details.
490 Alternative licensing for the compiler is available from Xamarin.
491
493 csharp(1), mono(1), pkg-config(1), sn(1)
494
496 To report bugs in the compiler, you must file them on our bug tracking
497 system, at: http://www.mono-project.com/community/bugs/
498
500 The Mono Mailing lists are listed at http://www.mono-project.com/commu‐
501 nity/help/mailing-lists/
502
504 The Mono C# compiler was developed by Novell, Inc (http://www.nov‐
505 ell.com) and Xamarin Inc (http://www.xamarin.com) is based on the ECMA
506 C# language standard available here:
507 http://www.ecma.ch/ecma1/STAND/ecma-334.htm
508 The home page for the Mono C# compiler is at http://www.mono-
510 project.com/docs/about-mono/languages/csharp/
511 6 January 2001 mcs(1)