examples: Fix echo by Reintroducing Concurrency #1107
Merged
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In #808, I've added an
.await?
to an instrumentedtokio::task::JoinHandle
since theInstrument
future now has a#[must_use]
. However, this caused the echo example to no longer accept multiple netcat connections but was only reported in #1097. This PR resolves this bug by instrumenting the spawned future, not theJoinHandle
.More broadly, I think the interaction between
tokio::task::JoinHandle
(which does not have the#[must_use]
annotation) and thetracing::Instrument
future (which does have the#[must_use]
annotation) is confusing and introduces performance footguns in refactors that even advanced users missed in code review.Resolves #1097.