Trait Process

Source

pub trait Process {
    type Stdout: AsyncRead + Send + Unpin;
    type Stderr: AsyncRead + Send + Unpin;

    // Required methods
    fn id(&self) -> Option<ProcessId>;
    fn send_signal(&mut self, signal: Signal) -> Result<(), ProcessError>;
    fn wait(
        &mut self,
    ) -> impl Future<Output = Result<ExitStatus, ProcessError>> + Send;
}

Expand description

Handle to one spawned child process.

Implementors expose the lifecycle operations the executor needs after spawn: identity (Self::id), signal delivery (Self::send_signal), and reaping (Self::wait).

stdout and stderr are NOT exposed through this trait. The ProcessSpawner::spawn call extracts them and returns them as fields on a Spawned value, which is the structural enforcement of the take-once invariant on those streams.

Required Associated Types§

Source

type Stdout: AsyncRead + Send + Unpin

Concrete async byte-stream type the implementation uses for the child’s stdout. Both StdProcess and the mock satisfy AsyncRead + Send + Unpin.

Source

type Stderr: AsyncRead + Send + Unpin

Concrete async byte-stream type the implementation uses for the child’s stderr.

Required Methods§

Source

fn id(&self) -> Option<ProcessId>

Numeric process id, or None once the child has been reaped (after Self::wait resolves).

Source

fn send_signal(&mut self, signal: Signal) -> Result<(), ProcessError>

Deliver signal to the child. Best-effort: returns as soon as the signal is queued by the kernel; does NOT wait for the child to acknowledge or terminate.

On Unix, the std backend targets the child’s process group (kill(-pgid, sig)) so any subprocesses the task itself forked also receive the signal (EXEC-013 step 2, EXEC-014). On non-Unix hosts, only Signal::Kill is implemented; Signal::Terminate and Signal::Interrupt surface std::io::ErrorKind::Unsupported.

§Errors

Returns ProcessError::SignalFailed when the OS rejects the signal (e.g. the child has already been reaped) or when the implementation does not support the requested variant on the host platform.

Source