fmt.Println(rb.Length())
	fmt.Println(rb.Free())

	// read
	buf := make([]byte, 4)
	rb.Read(buf)
	fmt.Println(string(buf))
}
```

It is possible to use an existing buffer with by replacing `New` with `NewBuffer`.


# Blocking vs Non-blocking

The default behavior of the ring buffer is non-blocking, 
meaning that reads and writes will return immediately with an error if the operation cannot be completed.

          "alg":"RS256",
          "kid":"2011-04-29"}
       ]
     }`

	pubKeys := publicKeys{
		RWMutex: &sync.RWMutex{},
		pkMap:   map[string]any{},
	}
	err := pubKeys.parseAndAdd(bytes.NewBuffer([]byte(jsonkey)))
	if err != nil {
		t.Fatal("Error loading pubkeys:", err)
	}
	if len(pubKeys.pkMap) != 1 {
		t.Fatalf("Expected 1 keys, got %d", len(pubKeys.pkMap))
	}

	slice, err := b.readSlice(delim)
	return string(slice), err
}

// NewBuffer creates and initializes a new [Buffer] using buf as its
// initial contents. The new [Buffer] takes ownership of buf, and the
// caller should not use buf after this call. NewBuffer is intended to
// prepare a [Buffer] to read existing data. It can also be used to set

	"reflect"
	"testing"

	"github.com/alecthomas/participle"
	"github.com/minio/minio/internal/s3select/jstream"
)

func getJSONStructs(b []byte) ([]any, error) {
	dec := jstream.NewDecoder(bytes.NewBuffer(b), 0).ObjectAsKVS().MaxDepth(100)
	var result []any
	for parsedVal := range dec.Stream() {
		result = append(result, parsedVal.Value)
	}
	if err := dec.Err(); err != nil {
		return nil, err
	}

			if err != nil {
				b.Fatal(err)
			}
			b.SetBytes(int64(len(f)))
			b.ReportAllocs()
			b.ResetTimer()
			var record sql.Record
			for b.Loop() {
				r := NewPReader(io.NopCloser(bytes.NewBuffer(f)), &ReaderArgs{})
				for {
					record, err = r.Read(record)
					if err != nil {
						break
					}
				}
				r.Close()
				if err != io.EOF {

			if err != nil {
				b.Fatal(err)
			}
			b.SetBytes(int64(len(f)))
			b.ReportAllocs()
			b.ResetTimer()
			var record sql.Record
			for b.Loop() {
				r := NewReader(io.NopCloser(bytes.NewBuffer(f)), &ReaderArgs{})
				for {
					record, err = r.Read(record)
					if err != nil {
						break
					}
				}
				r.Close()
				if err != io.EOF {

					if err != nil {
						t.Fatal(err)
					}
					dst <- *o
				default:
					t.Fatal("unexpected type:", typ.String())
				}
			}
			refDec := json.NewReader(io.NopCloser(bytes.NewBuffer(ref)), &json.ReaderArgs{ContentType: "json"})

			for {
				rec, err := dec.Read(nil)
				if err == io.EOF {
					break
				}
				if err != nil {
					t.Error(err)
				}

	if file != "" {
		distrib := make([][]string, setCount)
		b, err := os.ReadFile(file)
		if err != nil {
			log.Fatalln(err)
		}
		b = bytes.ReplaceAll(b, []byte("\r"), []byte{})
		sc := bufio.NewScanner(bytes.NewBuffer(b))
		for sc.Scan() {
			object = strings.TrimSpace(sc.Text())
			set := sipHashMod(prefix+object, setCount, id)
			distrib[set] = append(distrib[set], prefix+object)
		}
		for set, files := range distrib {

		b, e := io.ReadAll(r)
		if e != nil {
			return nil, e
		}
		b, _, minor, e := checkXL2V1(b)
		if e != nil {
			return nil, e
		}

		buf := bytes.NewBuffer(nil)
		var data xlMetaInlineData
		switch minor {
		case 0:
			_, e = msgp.CopyToJSON(buf, bytes.NewReader(b))
			if e != nil {
				return nil, e
			}
		case 1, 2:
			v, b, e := msgp.ReadBytesZC(b)

		b = strconv.AppendInt(b, int64(i), 10)
		b = append(b, ' ')
		buf.Write(b)
	}
	os.Stdout.Write(buf.Bytes())
	// Output: 0 1 2 3
}

func ExampleBuffer_Cap() {
	buf1 := bytes.NewBuffer(make([]byte, 10))
	buf2 := bytes.NewBuffer(make([]byte, 0, 10))
	fmt.Println(buf1.Cap())
	fmt.Println(buf2.Cap())
	// Output:
	// 10
	// 10
}

func ExampleBuffer_Grow() {
	var b bytes.Buffer
	b.Grow(64)
	bb := b.Bytes()