Cancellation and cancellation safety

Internal vs external cancellation Threads vs futures drop = cancel only at await points useful feature still somewhat abrubt and surprising Other cancellation mechanisms abort cancellation tokens

Cancellation safety

Not a memory safety issue or race condition Data loss or other logic errors Different definitions/names tokio's definition general definition/halt safety applying a replicated future idea Simple data loss Resumption Issue with select or similar in loops Splitting state between the future and the context as a root cause