[−][src]Crate bawawa
process management
this module provides some wrapping around the standard library's
std::process::Command
and std::process::Child
and associated
types.
Here we provide an opinionated API where we capture standard inputs and outputs by default. The errors are also wrapped to provide better understanding of what did fail (especially the PID or the command line).
There are a couple of items to keep in mind when utilising this API:
- as soon as
Process
is dropped the associated process will be terminated; Process
captures Stdout and Stderr, if you don't read the standard output it won't be visible on your terminal;Process
control Stdin too- the API utilizes the
Future
framework. If you don't push it in a runtime or callwait
the functions will do nothing.
the Program
Program
is an object that guarantees (within reason) the existence of a
program within the execution environment. When constructing, the Program
is checked so that once created it is known if it exists and if it has
appropriate execution rights.
let rustc = Program::new("rustc".to_owned())?;
the Command
this is the command line, the Program
, the parameters and the associated
environment variables necessary to spawn a new Process
.
let mut get_rustc_version = Command::new(rustc); get_rustc_version.arguments(&["--version"]); println!("{}", get_rustc_version);
spawn a Process
Once the Command
is ready with the appropriate parameter it is possible
to spawn a Process
. The trait Control
allows to follow the life
cycle of the spawned Process
.
let process = Process::spawn(get_rustc_version)?; println!("spawned command: '{}' (PID: {})", process.command(), process.id());
We provide functions to capture the standard output and standard error output
utilising the StandardOutput::capture_stdout
or StandardError::capture_stderr
and to send items to the standard inputs with StandardInput::send_stdin
.
let mut capture_stdout = process .capture_stdout( // specify the codec, the way to decode data // from the captured output. Here we read line // by line. tokio_codec::LinesCodec::new() ) .wait(); // from the _futures_ crate's Stream trait println!("compiler: {}", capture_stdout.next().unwrap()?); // compiler: rustc 1.35.0 (3c235d560 2019-05-20)
Structs
Capture | capture the standard output or standard error output from a running process |
Command | just like standard |
Error | The Error type. |
Process | a |
Program | a program, pre-checked and known to exist in the environment $PATH |
SendStdin | provide API to control the sending part to the standard input.
created from |
Enums
ErrorKind | The kind of an error. |
Traits
Control |
|
ResultExt | Additional methods for |
StandardError | Access the standard error output of a running |
StandardInput | Access the standard input of a running |
StandardOutput | Access the standard output of a running |
Type Definitions
Result | Convenient wrapper around |