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SharedArrayBuffer.prototype

The SharedArrayBuffer.prototype property represents the prototype for the SharedArrayBuffer object.

Property attributes of `SharedArrayBuffer.prototype`
Writable	no
Enumerable	no
Configurable	no

Description

SharedArrayBuffer instances inherit from SharedArrayBuffer.prototype. As with all constructors, you can change the constructor's prototype object to make changes to all SharedArrayBuffer instances.

Properties

SharedArrayBuffer.prototype.constructor: Specifies the function that creates an object's prototype. The initial value is the standard built-in SharedArrayBuffer constructor.
SharedArrayBuffer.prototype.byteLength Read only: The size, in bytes, of the array. This is established when the array is constructed and cannot be changed. Read only.

Methods

SharedArrayBuffer.prototype.slice(begin, end): Returns a new SharedArrayBuffer whose contents are a copy of this SharedArrayBuffer's bytes from begin, inclusive, up to end, exclusive. If either begin or end is negative, it refers to an index from the end of the array, as opposed to from the beginning.

Specifications

Specification	Status	Comment
ECMAScript Latest Draft (ECMA-262) The definition of 'SharedArrayBuffer.prototype' in that specification.	Draft	Initial definition in ES2017.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	68 68 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks. This was a temporary removal while mitigations were put in place.	No No Support was removed to mitigate speculative execution side-channel attacks (Windows blog).	57 Disabled 57 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog). Disabled From version 57: this feature is behind the `javascript.options.shared_memory` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config. 55 — 57 46 — 55 Disabled Disabled From version 46 until version 55 (exclusive): this feature is behind the `javascript.options.shared_memory` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	No	No	10.1 — ?

	Mobile
	Android webview	Chrome for Android	Edge Mobile	Firefox for Android	Opera for Android	iOS Safari	Samsung Internet
Basic support	60 — 63 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks. This is intended as a temporary measure until other mitigations are in place.	60 — 63 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks. This is intended as a temporary measure until other mitigations are in place.	?	57 Disabled 57 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog). Disabled From version 57: this feature is behind the `javascript.options.shared_memory` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config. 55 — 57 46 — 55 Disabled Disabled From version 46 until version 55 (exclusive): this feature is behind the `javascript.options.shared_memory` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	No	No	No