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See [`CmdqInner::receive_msg`]. > - pub(crate) fn receive_msg(&self, timeout: Delta) = -> Result > + /// Returns `ERANGE` if the message that arrives is not of type `M`.= See > + /// [`CmdqInner::receive_msg`]. > + fn receive_msg(&self, timeout: Delta) -> Result > where > // This allows all error types, including `Infallible`, to be us= ed for `M::InitError`. > Error: From, > { > self.inner.lock().receive_msg(timeout, None) > } > + > + /// Waits for an unsolicited GSP event of type `M`, dispatching any = other event that arrives > + /// first. > + /// > + /// # Errors > + /// > + /// - `ETIMEDOUT` if the event does not arrive within [`Self::RECEIV= E_TIMEOUT`] of the call, > + /// however many other events are dispatched while waiting. We also return the errors from `receive_msg`, this should be documented. > + pub(crate) fn await_msg(&self) -> Result > + where > + // This allows all error types, including `Infallible`, to be us= ed for `M::InitError`. > + Error: From, > + { > + let deadline =3D Instant::::now() + Self::RECEIVE_TIM= EOUT; > + loop { > + let remaining =3D deadline - Instant::::now(); > + if remaining.is_negative() { > + break Err(ETIMEDOUT); > + } > + match self.receive_msg::(remaining) { > + Ok(msg) =3D> break Ok(msg), > + Err(ERANGE) =3D> continue, > + Err(e) =3D> break Err(e), > + } > + } > + } Note that this will release the lock between calls to `receive_msg`. If a `send_command` comes in from another thread at the wrong time, that one *does* keep the lock until it has received the reply it expects - so our reply will be consumed silently and we will timeout. I guess you can just remove `Cmdq::receive_msg` here: acquire the lock at the beginning of `await_msg`, and call `inner.receive_msg` from it directly. The GSP queue is synchronous by design anyway, so that's what we want even if it looks strange to hold a lock for potentially 5 seconds.