How does Rust handle killing threads?

Question

Is there a parent-child connection between threads that are spawned? If I kill the thread from where I spawned other threads, are those going to get killed too? Is this OS specific?

Answer 1

How does Rust handle killing threads?

It doesn't; there is no way to kill a thread.

See also:

• How to terminate or suspend a Rust thread from another thread?
• How to check if a thread has finished in Rust?

Is there a parent-child connection between threads that are spawned?

When you spawn a thread, you get a JoinHandle that allows you to wait for the child thread to finish. The child does not know of the parent.

[what happens to the other threads] in the context of a thread panicking and dying

The documentation for thread::spawn covers this well:

The join handle will implicitly detach the child thread upon being dropped. In this case, the child thread may outlive the parent (unless the parent thread is the main thread; the whole process is terminated when the main thread finishes). Additionally, the join handle provides a join method that can be used to join the child thread. If the child thread panics, join will return an Err containing the argument given to panic.

That is, once a child thread has been started, what happens to the parent thread basically doesn't matter, unless the parent thread was the main thread, in which case the entire process is terminated.