ZeroTierOne/zeroidc/vendor/spin/README.md

spin-rs
===========

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This Rust library implements a simple
[spinlock](https://en.wikipedia.org/wiki/Spinlock), and is safe for `#[no_std]` environments.

Usage
-----

Include the following code in your Cargo.toml

```toml
[dependencies.spin]
version = "0.5"
```

Example
-------

When calling `lock` on a `Mutex` you will get a reference to the data. When this
reference is dropped, the lock will be unlocked.

```rust
extern crate spin;

fn main()
{
    let mutex   = spin::Mutex::new(0);
    let rw_lock = spin::RwLock::new(0);

    // Modify the data
    {
      let mut data = mutex.lock();
      *data = 2;
      let mut data = rw_lock.write();
      *data = 3;
    }

    // Read the data
    let answer =
    {
      let data1 = mutex.lock();
      let data2 = rw_lock.read();
      let data3 = rw_lock.read(); // sharing
      (*data1, *data2, *data3)
    };

    println!("Answers are {:?}", answer);
}
```

To share the lock, an `Arc<Mutex<T>>` may be used.

Remarks
-------

The behaviour of these lock is similar to their namesakes in `std::sync`. they
differ on the following:

 - The lock will not be poisoned in case of failure;