meson/docs/markdown/Commands.md

Command-line commands

There are two different ways of invoking Meson. First, you can run it directly from the source tree with the command /path/to/source/meson.py. Meson may also be installed in which case the command is simply meson. In this manual we only use the latter format for simplicity.

Meson is invoked using the following syntax: meson [COMMAND] [COMMAND_OPTIONS]

This section describes all available commands and some of their Optional arguments. The most common workflow is to run setup, followed by compile, and then install.

For the full list of all available options for a specific command use the following syntax: meson COMMAND --help

configure

{{ configure_usage.inc }}

Changes options of a configured meson project.

{{ configure_arguments.inc }}

Most arguments are the same as in setup.

Note: reconfiguring project will not reset options to their default values (even if they were changed in meson.build).

Examples:

List all available options:

meson configure builddir

Change value of a single option:

meson configure builddir -Doption=new_value

compile

(since 0.54.0)

{{ compile_usage.inc }}

Builds a default or a specified target of a configured Meson project.

{{ compile_arguments.inc }}

--verbose argument is available since 0.55.0.

Targets

(since 0.55.0)

TARGET has the following syntax [PATH/]NAME.SUFFIX[:TYPE], where:

• NAME: name of the target from meson.build (e.g. foo from executable('foo', ...)).
• SUFFIX: name of the suffix of the target from meson.build (e.g. exe from executable('foo', suffix: 'exe', ...)).
• PATH: path to the target relative to the root meson.build file. Note: relative path for a target specified in the root meson.build is ./.
• TYPE: type of the target. Can be one of the following: 'executable', 'static_library', 'shared_library', 'shared_module', 'custom', 'alias', 'run', 'jar'.

PATH, SUFFIX, and TYPE can all be omitted if the resulting TARGET can be used to uniquely identify the target in meson.build.

Note that SUFFIX did not exist prior to 1.3.0.

Backend specific arguments

(since 0.55.0)

BACKEND-args use the following syntax:

If you only pass a single string, then it is considered to have all values separated by commas. Thus invoking the following command:

$ meson compile --ninja-args=-n,-d,explain

would add -n, -d and explain arguments to ninja invocation.

If you need to have commas or spaces in your string values, then you need to pass the value with proper shell quoting like this:

$ meson compile "--ninja-args=['a,b', 'c d']"

Examples:

Build the project:

meson compile -C builddir

Execute a dry run on ninja backend with additional debug info:

meson compile --ninja-args=-n,-d,explain

Build three targets: two targets that have the same foo name, but different type, and a bar target:

meson compile foo:shared_library foo:static_library bar

Produce a coverage html report (if available):

ninja coverage-html

dist

(since 0.52.0)

{{ dist_usage.inc }}

Generates a release archive from the current source tree.

{{ dist_arguments.inc }}

See notes about creating releases for more info.

Examples:

Create a release archive:

meson dist -C builddir

init

(since 0.45.0)

{{ init_usage.inc }}

Creates a basic set of build files based on a template.

{{ init_arguments.inc }}

Examples:

Create a project in sourcedir:

meson init -C sourcedir

env2mfile

This command is experimental and subject to change.

{Since 0.62.0}

{{ env2mfile_usage.inc }}

Create native and cross files from the current environment, typically by sniffing environment variables like CC and CFLAGS.

{{ env2mfile_arguments.inc }}

Examples:

Autodetect the current cross build environment:

meson env2mfile --cross -o current_cross.txt --cpu=arm7a --cpu-family=arm --system=linux

Generate a cross build using Debian system information:

meson env2mfile --cross --debarch=armhf -o deb_arm_cross.txt

introspect

{{ introspect_usage.inc }}

Displays information about a configured Meson project.

{{ introspect_arguments.inc }}

Examples:

Display basic information about a configured project in builddir:

meson introspect builddir --projectinfo

install

(since 0.47.0)

{{ install_usage.inc }}

Installs the project to the prefix specified in setup.

{{ install_arguments.inc }}

See the installation documentation for more info.

Examples:

Install project to prefix:

meson install -C builddir

Install project to $DESTDIR/prefix:

DESTDIR=/path/to/staging/area meson install -C builddir

Since 0.60.0 DESTDIR and --destdir can be a path relative to build directory. An absolute path will be set into environment when executing scripts.

reprotest

(since 1.6.0)

{{ reprotest_usage.inc }}

Simple reproducible build tester that compiles the project twice and checks whether the end results are identical.

This command must be run in the source root of the project you want to test.

{{ reprotest_arguments.inc }}

Examples

meson reprotest

Builds the current project with its default settings.

meson reprotest --intermediaries -- --buildtype=debugoptimized

Builds the target and also checks that all intermediate files like object files are also identical. All command line arguments after the -- are passed directly to the underlying meson invocation. Only use option arguments, i.e. those that start with a dash, Meson sets directory arguments automatically.

rewrite

(since 0.50.0)

{{ rewrite_usage.inc }}

Modifies the Meson project.

{{ rewrite_arguments.inc }}

See the Meson file rewriter documentation for more info.

setup

{{ setup_usage.inc }}

Configures a build directory for the Meson project.

Deprecated since 0.64.0: This is the default Meson command (invoked if there was no COMMAND supplied). However, supplying the command is necessary to avoid clashes with future added commands, so "setup" should be used explicitly.

Since 1.1.0 --reconfigure is allowed even if the build directory does not already exist, that argument is ignored in that case.

Since 1.3.0 If the build directory already exists, options are updated with their new value given on the command line (-Dopt=value). Unless --reconfigure is also specified, this won't reconfigure immediately. This has the same behaviour as meson configure <builddir> -Dopt=value.

Since 1.3.0 It is possible to clear the cache and reconfigure in a single command with meson setup --clearcache --reconfigure <builddir>.

{{ setup_arguments.inc }}

See Meson introduction page for more info.

Examples:

Configures builddir with default values:

meson setup builddir

subprojects

(since 0.49.0)

{{ subprojects_usage.inc }}

Manages subprojects of the Meson project. Since 0.59.0 commands are run on multiple subprojects in parallel by default, use --num-processes=1 if it is not desired.

Since 0.64.0 the update subcommand will not download new wrap files from WrapDB any more. Use meson wrap update command for that instead.

{{ subprojects_arguments.inc }}

test

{{ test_usage.inc }}

Run tests for the configure Meson project.

{{ test_arguments.inc }}

See the unit test documentation for more info.

Since 1.2.0 you can use wildcards in args for test names. For example, "bas*" will match all test with names beginning with "bas".

Since 1.2.0 it is an error to provide a test name or wildcard that does not match any test.

Examples:

Run tests for the project:

meson test -C builddir

Run only specific_test_1 and specific_test_2:

meson test -C builddir specific_test_1 specific_test_2

wrap

{{ wrap_usage.inc }}

An utility to manage WrapDB dependencies.

{{ wrap_arguments.inc }}

See the WrapDB tool documentation for more info.

devenv

(since 0.58.0)

{{ devenv_usage.inc }}

Runs a command, or open interactive shell if no command is provided, with environment setup to run project from the build directory, without installation.

We automatically handle bash and set $PS1 accordingly. If the automatic $PS1 override is not desired (maybe you have a fancy custom prompt), set the $MESON_DISABLE_PS1_OVERRIDE environment variable and use $MESON_PROJECT_NAME when setting the custom prompt, for example with a snippet like the following:

...
if [[ -n "${MESON_PROJECT_NAME-}" ]];
then
  PS1+="[ ${MESON_PROJECT_NAME} ]"
fi
...

These variables are set in environment in addition to those set using meson.add_devenv:

• MESON_DEVENV is defined to '1'.
• MESON_PROJECT_NAME is defined to the main project's name.
• PKG_CONFIG_PATH includes the directory where Meson generates -uninstalled.pc files.
• PATH includes every directory where there is an executable that would be installed into bindir. On windows it also includes every directory where there is a DLL needed to run those executables.
• LD_LIBRARY_PATH includes every directory where there is a shared library that would be installed into libdir. This allows to run system application using custom build of some libraries. For example running system GEdit when building GTK from git. On OSX the environment variable is DYLD_LIBRARY_PATH and PATH on Windows.
• GI_TYPELIB_PATH includes every directory where a GObject Introspection typelib is built. This is automatically set when using gnome.generate_gir().
• GSETTINGS_SCHEMA_DIR Since 0.59.0 includes every directory where a GSettings schemas is compiled. This is automatically set when using gnome.compile_schemas(). Note that this requires GLib >= 2.64 when gnome.compile_schemas() is used in more than one directory.
• QEMU_LD_PREFIX Since 1.0.0 is set to the sys_root value from cross file when cross compiling and that property is defined.

Since 0.62.0 if bash-completion scripts are being installed and the shell is bash, they will be automatically sourced.

Since 0.62.0 when GDB helper scripts (*-gdb.py, *-gdb.gdb, and *-gdb.csm) are installed with a library name that matches one being built, Meson adds the needed auto-load commands into <builddir>/.gdbinit file. When running gdb from top build directory, that file is loaded by gdb automatically. In the case of python scripts that needs to load other python modules, PYTHONPATH may need to be modified using meson.add_devenv().

Since 0.63.0 when cross compiling for Windows WINEPATH is used instead of PATH which allows running Windows executables using wine. Note that since WINEPATH size is currently limited to 1024 characters, paths relative to the root of build directory are used. That means current workdir must be the root of build directory when running wine.

Since 1.1.0 meson devenv --dump [<filename>] command takes an optional filename argument to write the environment into a file instead of printing to stdout.

Since 1.1.0 --dump-format argument has been added to select which shell format should be used. There are currently 3 formats supported:

• sh: Lines are in the format VAR=/prepend:$VAR:/append.
• export: Same as sh but with extra export VAR lines.
• vscode: Same as sh but without $VAR substitution because they do not seems to be properly supported by vscode.

{{ devenv_arguments.inc }}

format

(since 1.5.0)

{{ format_usage.inc }}

Format specified meson.build documents. For compatibility with muon, fmt is an alias to format.

{{ format_arguments.inc }}

The configuration file is a .ini file. If a meson.format file exists beside the provided build file to analyze, and no configuration file is provided on the command line, the meson.format file is automatically used.

If no build file is provided on the command line, the meson.build file in current directory is analyzed.

The following options are recognized:

• max_line_length (int): When an array, a dict, a function or a method would be longer that this, it is formatted one argument per line (Default is 80).
• indent_by (str): Indentation to use (Default is four spaces ' ').
• space_array (bool): Whether to add spaces between [] and array arguments (default is false).
• kwargs_force_multiline (bool): If true, arguments are formatted one per line as soon as there is a keyword argument (default is false).
• wide_colon (bool): If true, a space is placed before colon in dict and in keyword arguments (default is false).
• no_single_comma_function (bool): If true, a comma is never appended to function arguments if there is only one argument, even if using multiline arguments (default is false).
• end_of_line ('cr', 'lf', 'crlf', 'native'): Line ending to use (applied when using --output or --inline argument) (default is 'native).
• indent_before_comments (str): Indentation to use before inline comments (default is two spaces ' ').
• simplify_string_literals (bool): When true, multiline strings are converted to single line strings if they don't contain newlines. Formatted strings are converted to normal strings if they don't contain substitutions (default is true).
• insert_final_newline (bool): If true, force the meson.build file to end with a newline character (default is true).
• tab_width (int): Width of tab stops, used to compute line length when indent_by uses tab characters (default is 4).
• sort_files (bool): When true, arguments of files() function are sorted alphabetically (default is false).
• group_arg_value (bool): When true, string argument with -- prefix followed by string argument without -- prefix are grouped on the same line, in multiline arguments (default is false).
• use_editor_config (bool): When true, also uses config from .editorconfig .

The first six options are the same than for the muon fmt command.

It is also possible to use a .editorconfig file, by providing the --editor-config option on the command line, or with the use_editor_config option in the config file.

When --recursive option is specified, meson.build files from subdir are also analyzed (must be used in conjunction with --inplace or --check-only option).

Differences with muon fmt

The meson format command should be compatible with the muon fmt command. However, it has more features, and some differences:

• By default, meson format put two spaces before inline comments, while muon fmt only puts one.
• muon fmt can potentially mix crlf and lf end-of-lines, as it is not aware of them. meson format will always be consistent in the output it produces.
• muon fmt only recognize the indent_by option from .editorconfig files. meson format also recognizes max_line_length, end_of_line, insert_final_newline and tab_width options.
• meson format has many additional format rules (see option list above).