// CopyBytesToJS copies bytes from src to dst.
// It panics if dst is not a Uint8Array or Uint8ClampedArray.
// It returns the number of bytes copied, which will be the minimum of the lengths of src and dst.
func CopyBytesToJS(dst Value, src []byte) int {
	n, ok := copyBytesToJS(dst.ref, src)
	runtime.KeepAlive(dst)
	if !ok {

	}

	if faketime && (fd == 1 || fd == 2) {
		n := faketimeWrite(fd, b)
		if n < 0 {
			return 0, errnoErr(Errno(-n))
		}
		return n, nil
	}

	buf := uint8Array.New(len(b))
	js.CopyBytesToJS(buf, b)
	n, err := fsCall("write", fd, buf, 0, len(b), nil)
	if err != nil {
		return 0, err
	}
	n2 := n.Int()
	f.pos += int64(n2)
	return n2, err
}

						const toCopy = src.subarray(0, dst.length);
						dst.set(toCopy);
						setInt64(sp + 40, toCopy.length);
						this.mem.setUint8(sp + 48, 1);
					},

					// func copyBytesToJS(dst ref, src []byte) (int, bool)
					"syscall/js.copyBytesToJS": (sp) => {
						sp >>>= 0;
						const dst = loadValue(sp + 8);
						const src = loadSlice(sp + 16);
						if (!(dst instanceof Uint8Array || dst instanceof Uint8ClampedArray)) {

		if err != nil {
			req.Body.Close() // RoundTrip must always close the body, including on errors.
			return nil, err
		}
		req.Body.Close()
		if len(body) != 0 {
			buf := uint8Array.New(len(body))
			js.CopyBytesToJS(buf, body)
			opt.Set("body", buf)
		}
	}

	fetchPromise := js.Global().Call("fetch", req.URL.String(), opt)
	var (
		respCh           = make(chan *Response, 1)
		errCh            = make(chan error, 1)

			src := make([]byte, tt.srcLen)
			if tt.srcLen >= 2 {
				src[1] = 42
			}
			dst := js.Global().Get("Uint8Array").New(tt.dstLen)

			if got, want := js.CopyBytesToJS(dst, src), tt.copyLen; got != want {
				t.Errorf("copied %d, want %d", got, want)
			}
			if tt.dstLen >= 2 {
				if got, want := dst.Index(1).Int(), 42; got != want {
					t.Errorf("got %d, want %d", got, want)

		{"XP1_SUPPORT_BROADCAST", Const, 2},
		{"XP1_SUPPORT_MULTIPOINT", Const, 2},
		{"XP1_UNI_RECV", Const, 2},
		{"XP1_UNI_SEND", Const, 2},
	},
	"syscall/js": {
		{"CopyBytesToGo", Func, 0},
		{"CopyBytesToJS", Func, 0},
		{"Error", Type, 0},
		{"Func", Type, 0},
		{"FuncOf", Func, 0},
		{"Global", Func, 0},
		{"Null", Func, 0},
		{"Type", Type, 0},
		{"TypeBoolean", Const, 0},