Atomics.waitAsync()

Baseline 2025

202511

Atomics.waitAsync() "not-equal" value 0 "timed-out" value Promise Atomics.notify() "ok" "timed-out"

Atomics.waitAsync() Atomics.notify()

Atomics.waitAsync(typedArray, index, value)
Atomics.waitAsync(typedArray, index, value, timeout)

async: value Promise
value: async false "not-equal" "timed-out" timeout 0 async true "ok" "timed-out" (Promise)

Int32Array

const sab = new SharedArrayBuffer(1024);
const int32 = new Int32Array(sab);

0 0 result.value

const result = Atomics.waitAsync(int32, 0, 0, 1000);
// { async: true, value: Promise {<pending>} }

0 "ok"

Atomics.notify(int32, 0);
// { async: true, value: Promise {<fulfilled>: 'ok'} }

"ok" value "not-equal" "time-out"


ECMAScript 2027 LanguageSpecification # sec-atomics.waitasync

MDN

MDN 2025725

GitHub