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+---
+short-description: Running external commands
+...
+
+# External commands
+
+As a part of the software configuration, you may want to get extra
+data by running external commands. The basic syntax is the following.
+
+```meson
+r = run_command('command', 'arg1', 'arg2', 'arg3')
+if r.returncode() != 0
+  # it failed
+endif
+output = r.stdout().strip()
+errortxt = r.stderr().strip()
+```
+
+Since 0.52.0, you can pass the command environment as a dictionary:
+
+```meson
+run_command('command', 'arg1', 'arg2', env: {'FOO': 'bar'})
+```
+
+Since 0.50.0, you can also pass the command
+[`environment`](Reference-manual.md#environment-object) object:
+
+```meson
+env = environment()
+env.set('FOO', 'bar')
+run_command('command', 'arg1', 'arg2', env: env)
+```
+
+The `run_command` function returns an object that can be queried for
+return value and text written to stdout and stderr. The `strip` method
+call is used to strip trailing and leading whitespace from strings.
+Usually output from command line programs ends in a newline, which is
+unwanted in string variables. The first argument can be either a
+string or an executable you have detected earlier with `find_program`.
+
+Meson will autodetect scripts with a shebang line and run them with
+the executable/interpreter specified in it both on Windows and on
+Unixes.
+
+Note that you can not pass your command line as a single string. That
+is, calling `run_command('do_something foo bar')` will not work. You
+must either split up the string into separate arguments or pass the
+split command as an array. It should also be noted that Meson will not
+pass the command to the shell, so any command lines that try to use
+things such as environment variables, backticks or pipelines will not
+work. If you require shell semantics, write your command into a script
+file and call that with `run_command`.