Struct FormationLifeline 

pub struct FormationLifeline { /* private fields */ }

A member’s read end of its formation lifeline, owned by this process alone.

Implementations

impl FormationLifeline

pub fn from_env() -> Result<Option<Self>, RuntimeError>

This process’s formation lifeline, read from FORMATION_LIFELINE_ENV.

Ok(None) when the variable is absent or blank. Otherwise the value must be the decimal number, 3 or above, of an open descriptor that is a FIFO opened read-only; anything else is an error, as is a second read of a set variable in the same process. On success the descriptor has FD_CLOEXEC set and is owned by the returned value.

pub fn watch(self, on_closed: impl FnOnce() + Send + 'static) -> Result<()>

Hand the lifeline to a detached thread that blocks on it and calls on_closed once, at EOF. EOF that came before this call is seen at once.

The thread owns the descriptor from here on; nothing else in the process holds or closes it. Errors only when the thread cannot be started.

Trait Implementations

impl Debug for FormationLifeline

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

Formats the value using the given formatter.