Struct FilesystemPoller 

pub struct FilesystemPoller { /* private fields */ }

Polls a set of filesystem paths for modification-time changes.

Each watched path is associated with the SystemTime of its last observed modification. On every (un-throttled) poll the current mtime of each path is compared against the recorded value to produce PolledChange events.

See the module documentation for the throttling and created-vs-modified semantics.

Implementations

impl FilesystemPoller

pub fn new(poll_interval: Duration) -> Self

Create a poller with an explicit throttling interval.

pub fn with_default_interval() -> Self

Create a poller using the default 250 ms throttling interval.

pub fn register_path<P: AsRef<Path>>(&mut self, path: P) -> Result<()>

Start watching path, seeding the modification-time table from the file’s current mtime.

Errors

Propagates any std::io::Error from reading the file’s metadata or modification time — most commonly std::io::ErrorKind::NotFound when the file does not exist. To watch a not-yet-created path use Self::track_expected instead.

pub fn track_expected<P: AsRef<Path>>(&mut self, path: P)

Track a path that may not exist yet.

The path is recorded with a SystemTime::UNIX_EPOCH sentinel so that when the file later appears the next poll reports it as PolledChangeKind::Created (rather than PolledChangeKind::Modified). While the file is still absent the sentinel suppresses any PolledChangeKind::Deleted event — the path simply waits to appear. This also re-arms creation detection for a path that was previously dropped after a deletion.

pub fn deregister_path<P: AsRef<Path>>(&mut self, path: P) -> bool

Stop watching path.

Returns true if the path was being watched, false otherwise.

pub fn watched_paths(&self) -> Vec<PathBuf>

Return all currently watched paths, sorted ascending for deterministic diagnostics.

pub fn watched_count(&self) -> usize

Number of paths currently being watched.

pub fn poll(&mut self) -> Vec<PolledChange>

Poll for changes, honouring the configured throttling interval.

If a previous poll occurred less than poll_interval ago this returns an empty vector without touching the filesystem. Otherwise it records the current instant and runs the full comparison.

pub fn force_poll(&mut self) -> Vec<PolledChange>

Poll for changes immediately, ignoring the throttling interval.

The throttle clock is still updated so that a subsequent Self::poll is measured relative to this call.