Struct WatchReceiver 

pub struct WatchReceiver { /* private fields */ }

Receiving half of a fabric watch channel.

Reads the current value from shared memory and tracks the last-seen version to detect changes. Multiple receivers can be created from the same base offset (each tracking its own version independently).

Implementations

impl WatchReceiver

pub fn recv(&mut self) -> Result<Vec<u8>>

Read the current value from shared memory.

Updates the receiver’s tracked version to the current version, so subsequent calls to changed will return false until the sender publishes a new value.

pub fn changed(&self) -> Result<bool>

Check whether the value has changed since the last recv call.

Compares the current version in shared memory against the version recorded during the last recv(). Does not update the tracked version; call recv() to consume the change.

pub fn wait_for_change(&mut self, max_polls: u32) -> Result<Vec<u8>>

Poll until the version changes, up to max_polls iterations.

Combines changed and recv in a tight loop. Returns the new value once a change is detected, or grafos_std::error::FabricError::LeaseExpired if max_polls is exhausted without observing a version change.

pub fn version(&self) -> Result<u64>

Read the current version counter from shared memory.

This returns the version stored in the arena, not the receiver’s last-seen version. Compare with the result of a previous recv() to detect changes, or use changed for convenience.