ReadableStreamDefaultReader: releaseLock() method

{{APIRef("Streams")}}{{AvailableInWorkers}}

The releaseLock() method of the {{domxref("ReadableStreamDefaultReader")}} interface releases the reader's lock on the stream.

If the associated stream is errored when the lock is released, the reader will appear errored in that same way subsequently; otherwise, the reader will appear closed.

If the reader's lock is released while it still has pending read requests then the promises returned by the reader's {{domxref("ReadableStreamDefaultReader.read()")}} method are immediately rejected with a TypeError. Unread chunks remain in the stream's internal queue and can be read later by acquiring a new reader.

Syntax

releaseLock()

Parameters

None.

Return value

None ({{jsxref("undefined")}}).

Exceptions

• {{jsxref("TypeError")}}
  • : Thrown if the source object is not a ReadableStreamDefaultReader.

Examples

function fetchStream() {
  const reader = stream.getReader();

  // …

  reader.releaseLock();

  // …
}

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("ReadableStreamDefaultReader.ReadableStreamDefaultReader", "ReadableStreamDefaultReader()")}} constructor
• Using readable streams