start static method Null safety
Starts a process running the executable
with the specified
arguments
.
Returns a Future<Process>
that completes with a
Process
instance when the process has been successfully
started. That Process
object can be used to interact with the
process. If the process cannot be started the returned Future
completes with an exception.
Use workingDirectory
to set the working directory for the process. Note
that the change of directory occurs before executing the process on some
platforms, which may have impact when using relative paths for the
executable and the arguments.
Use environment
to set the environment variables for the process. If not
set the environment of the parent process is inherited. Currently, only
US-ASCII environment variables are supported and errors are likely to occur
if an environment variable with code-points outside the US-ASCII range is
passed in.
If includeParentEnvironment
is true
, the process's environment will
include the parent process's environment, with environment
taking
precedence. Default is true
.
If runInShell
is true
, the process will be spawned through a system
shell. On Linux and OS X, /bin/sh
is used, while
%WINDIR%\system32\cmd.exe
is used on Windows.
Users must read all data coming on the stdout and stderr
streams of processes started with Process.start
. If the user
does not read all data on the streams the underlying system
resources will not be released since there is still pending data.
The following code uses Process.start
to grep for main
in the
file test.dart
on Linux.
var process = await Process.start('grep', ['-i', 'main', 'test.dart']);
stdout.addStream(process.stdout);
stderr.addStream(process.stderr);
If mode
is ProcessStartMode.normal (the default) a child
process will be started with stdin
, stdout
and stderr
connected.
If mode
is ProcessStartMode.detached a detached process will
be created. A detached process has no connection to its parent,
and can keep running on its own when the parent dies. The only
information available from a detached process is its pid
. There
is no connection to its stdin
, stdout
or stderr
, nor will
the process' exit code become available when it terminates.
If mode
is ProcessStartMode.detachedWithStdio a detached
process will be created where the stdin
, stdout
and stderr
are connected. The creator can communicate with the child through
these. The detached process will keep running even if these
communication channels are closed. The process' exit code will
not become available when it terminated.
The default value for mode
is ProcessStartMode.normal
.
Implementation
external static Future<Process> start(
String executable, List<String> arguments,
{String? workingDirectory,
Map<String, String>? environment,
bool includeParentEnvironment = true,
bool runInShell = false,
ProcessStartMode mode = ProcessStartMode.normal});