diff --git a/library/std/src/thread/mod.rs b/library/std/src/thread/mod.rs index ffdf4be158457..d1fe9260e529c 100644 --- a/library/std/src/thread/mod.rs +++ b/library/std/src/thread/mod.rs @@ -965,10 +965,13 @@ pub fn park_timeout(dur: Duration) { /// A unique identifier for a running thread. /// -/// A `ThreadId` is an opaque object that has a unique value for each thread -/// that creates one. `ThreadId`s are not guaranteed to correspond to a thread's -/// system-designated identifier. A `ThreadId` can be retrieved from the [`id`] -/// method on a [`Thread`]. +/// A `ThreadId` is an opaque object that uniquely identifies each thread +/// created during the lifetime of a process. `ThreadId`s are guaranteed not to +/// be reused, even when a thread terminates. `ThreadId`s are under the control +/// of Rust's standard library and there may not be any relationship between +/// `ThreadId` and the underlying platform's notion of a thread identifier -- +/// the two concepts cannot, therefore, be used interchangeably. A `ThreadId` +/// can be retrieved from the [`id`] method on a [`Thread`]. /// /// # Examples ///