Rust: What is the difference between sync::Condvar and tokio::sync::Notify?

sync::Condvar — blocking condition. tokio::sync::Notify — async notification.

sync::Condvar:

• Blocking.
• Condition variable.
• For sync code.

tokio::sync::Notify:

• Async.
• Notification.
• For async code.

1// Blocking
2use std::sync::{Condvar, Mutex};
3let pair = (Mutex::new(false), Condvar::new());
4
5// Async
6use tokio::sync::Notify;
7let notify = Notify::new();
8notify.notify_one();

Key: Condvar for blocking, Notify for async.