# Crossbeam Channel
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https://crates.io/crates/crossbeam-channel)
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This crate provides multi-producer multi-consumer channels for message passing.
It is an alternative to [`std::sync::mpsc`] with more features and better performance.
Some highlights:
* [`Sender`]s and [`Receiver`]s can be cloned and shared among threads.
* Two main kinds of channels are [`bounded`] and [`unbounded`].
* Convenient extra channels like [`after`], [`never`], and [`tick`].
* The [`select!`] macro can block on multiple channel operations.
* [`Select`] can select over a dynamically built list of channel operations.
* Channels use locks very sparingly for maximum [performance](benchmarks).
[`std::sync::mpsc`]: https://doc.rust-lang.org/std/sync/mpsc/index.html
[`Sender`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/struct.Sender.html
[`Receiver`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/struct.Receiver.html
[`bounded`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/fn.bounded.html
[`unbounded`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/fn.unbounded.html
[`after`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/fn.after.html
[`never`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/fn.never.html
[`tick`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/fn.tick.html
[`select!`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/macro.select.html
[`Select`]: https://docs.rs/crossbeam-channel/*/crossbeam_channel/struct.Select.html
## Usage
Add this to your `Cargo.toml`:
```toml
[dependencies]
crossbeam-channel = "0.4"
```
Next, add this to your crate:
```rust
#[macro_use]
extern crate crossbeam_channel;
```
## Compatibility
The minimum supported Rust version is 1.28. Any change to this is considered a breaking change.
## License
Licensed under either of
* Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
at your option.
#### Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.
#### Third party software
This product includes copies and modifications of software developed by third parties:
* [examples/matching.rs](examples/matching.rs) includes
[matching.go](http://www.nada.kth.se/~snilsson/concurrency/src/matching.go) by Stefan Nilsson,
licensed under Creative Commons Attribution 3.0 Unported License.
* [src/flavors/array.rs](src/flavors/array.rs) is based on
[Bounded MPMC queue](http://www.1024cores.net/home/lock-free-algorithms/queues/bounded-mpmc-queue)
by Dmitry Vyukov, licensed under the Simplified BSD License and the Apache License, Version 2.0.
* [tests/mpsc.rs](tests/mpsc.rs) includes modifications of code from The Rust Programming Language,
licensed under the MIT License and the Apache License, Version 2.0.
* [tests/golang.rs](tests/golang.rs) is based on code from The Go Programming Language, licensed
under the 3-Clause BSD License.
See the source code files for more details.
Copies of third party licenses can be found in [LICENSE-THIRD-PARTY](LICENSE-THIRD-PARTY).