Struct LaunchedChild 

pub struct LaunchedChild {
    pub workdir: PathBuf,
    pub session_id: String,
    pub records_dir: PathBuf,
    pub capsule_url: String,
    pub argv: Vec<String>,
    pub env: Vec<(String, String)>,
    pub delegation_id: Option<String>,
    pub door_token: Option<DoorToken>,
    pub formation_id: Option<FormationId>,
    pub workdir_snapshot: Option<WorkdirSnapshot>,
    /* private fields */
}

A running child capsule and the handles to end it.

Fields

workdir: PathBuf

The directory the parent created for this child in its records directory’s [CHILDREN_DIR], and passed as its --workdir: the child’s work folder. Its trace, its completion.json and an agent child’s out/ are in Self::records_dir.

session_id: String

The session id the child’s runtime minted for itself.

records_dir: PathBuf

The child’s records directory, as the child reported it on its readiness line: where its trace, its completion.json and an agent child’s out/ are. Never derived from Self::workdir.

capsule_url: String

The child’s A2A endpoint, http://host:port. Empty for a script capsule, which binds no port and has already finished by the time it reports.

argv: Vec<String>

The argument vector the parent built, in order, starting with the binary.

Exposed so a caller — a test, notably — can assert what was passed without reading /proc. It carries no token: the approval goes in on standard input.

env: Vec<(String, String)>

The complete environment the parent built for this child, in insertion order. Also carries no token.

delegation_id: Option<String>

The id this launch’s completion reports under, None when no spawner was supplied.

Minted here, injected into the child as part of SPAWNER_ENV, and echoed back on the completion — the one value that joins a delegation to the task it produces at the parent.

door_token: Option<DoorToken>

The operator token of a child that declares network.authentication, read from tokens.operator on its readiness line. The parent presents it on every call to the child’s door. Never printed by Debug.

formation_id: Option<FormationId>

The formation the child reports it joined, read from formation_id on its readiness line. None when the line carries no such key, or a value that is not a formation id.

workdir_snapshot: Option<WorkdirSnapshot>

What was copied from the parent’s work folder into Self::workdir before the child started, or None for a child that started in an empty one.

Implementations

impl LaunchedChild

pub fn pid(&self) -> u32

The child’s operating-system process id. 0 once it has been reaped.

pub fn stderr_tail(&self) -> Vec<String>

The child’s last [CHILD_STDERR_TAIL_LINES] lines, oldest first.

The same lines a crash completion quotes back, exposed so a caller can read what the child said without scraping the stderr they were already echoed to.

pub fn begin_ending(&self)

Mark the ending deliberate and send the child SIGTERM, without waiting for it.

A parent ending several children calls this on each before Self::shutdown or Drop on any, so they wind down together and the whole ending waits one CHILD_END_GRACE rather than one per child. A child already exited is left to be reaped.

pub fn shutdown(&mut self) -> Result<(), RuntimeError>

End the child — SIGTERM, up to CHILD_END_GRACE to exit, then SIGKILL — and reap it. Idempotent: a second call, or a call after Drop has already run, does nothing.

Marks the ending as deliberate, so the watcher records the delegation as terminated and posts nothing: the only party that would be told is the party that did it.

pub fn is_being_ended(&self) -> bool

Whether the child is winding down from a deliberate SIGTERM and has not been reaped.

The door asks this of a completion that arrives for a delegation still in the set: such a completion is the child’s own account of a cancel its parent’s side chose, posted before the launcher’s terminated record replaces it, and it is not the delegation’s outcome.

pub fn watcher_finished(&self) -> bool

Whether the completion watcher behind this child has finished: it has seen the child end and recorded, and posted, whatever it records and posts. true for a child no watcher observes.

A delegating task that ends a child asks this before it lets the child’s handle go, so the child’s completion.json says how it ended before the parent’s own process can exit.

pub fn has_exited(&self) -> bool

Whether the child’s process has ended, by its own exit or by being ended. The completion watcher’s own poll: a process that exited on its own is reaped and its lifeline closed.

Never blocks: a delegating task asks this while it gives a child that has just reported its outcome a moment to finish exiting.

Trait Implementations

impl Debug for LaunchedChild

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for LaunchedChild

fn drop(&mut self)

Ends and reaps as LaunchedChild::shutdown does, so a parent that returns early — including by panicking — leaves no orphaned capsule process behind holding a port and a directory. Deliberate on the same terms. A child that has already exited is only reaped.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.