switch t.tok {
	case '\n':
		t.line++
	case '-':
		if s.Peek() == '>' {
			s.Next()
			t.tok = ARR
			return ARR
		}
	case '@':
		if s.Peek() == '>' {
			s.Next()
			t.tok = ROT
			return ROT
		}
	case '<':
		if s.Peek() == '<' {
			s.Next()
			t.tok = LSH
			return LSH
		}
	case '>':
		if s.Peek() == '>' {
			s.Next()
			t.tok = RSH
			return RSH
		}
	}

![Erasure](https://github.com/minio/minio/blob/master/docs/screenshots/erasure-code.jpg?raw=true)

## What is Bit Rot protection?

Bit Rot, also known as data rot or silent data corruption is a data loss issue faced by disk drives today. Data on the drive may silently get corrupted without signaling an error has occurred, making bit rot more dangerous than a permanent hard drive failure.

	case arg_const:
		v := x & (1<<8 - 1)
		rot := (x >> 8) & (1<<4 - 1) * 2
		if rot > 0 && v&3 == 0 {
			// could rotate less
			return ImmAlt{uint8(v), uint8(rot)}
		}
		if rot >= 24 && ((v<<(32-rot))&0xFF)>>(32-rot) == v {
			// could wrap around to rot==0.
			return ImmAlt{uint8(v), uint8(rot)}
		}
		return Imm(v>>rot | v<<(32-rot))

	case arg_endian:
		return Endian((x >> 9) & 1)

		max := udivisible(n, int64(c)).max
		mask := ^uint64(0) >> (64 - n)
		for i := uint64(0); i < maxU; i++ {
			want := i%c == 0
			mul := (i * m) & mask
			rot := (mul>>uint(k) | mul<<(n-uint(k))) & mask
			got := rot <= max
			if want != got {
				t.Errorf("unsigned divisible wrong for %d %% %d == 0: got %v, want %v (k=%d,m=%d,max=%d)\n", i, c, got, want, k, m, max)
			}
		}
	}
}

type wholeBitrotReader struct {
	disk       StorageAPI
	volume     string
	filePath   string
	verifier   *BitrotVerifier // Holds the bit-rot info
	tillOffset int64           // Affects the length of data requested in disk.ReadFile depending on Read()'s offset
	buf        []byte          // Holds bit-rot verified data
}

func (b *wholeBitrotReader) ReadAt(buf []byte, offset int64) (n int, err error) {
	if b.buf == nil {

						qst, err = bfs.SysBlockDeviceQueueStats(parentDev)
					}
				}
				if err == nil {
					info.NRRequests = qst.NRRequests
					rot := qst.Rotational == 1 // Rotational is '1' if the device is HDD
					info.Rotational = &rot
				}
			}
		}
	}

	return info, nil
}

// GetDriveStats returns IO stats of the drive by its major:minor

	LSH          ScanToken = -1000 - iota // << Left shift.
	RSH                                   // >> Logical right shift.
	ARR                                   // -> Used on ARM for shift type 3, arithmetic right shift.
	ROT                                   // @> Used on ARM for shift type 4, rotate right.
	Include                               // included file started here
	BuildComment                          // //go:build or +build comment

// errFileCorrupt - file has an unexpected size, or is not readable
var errFileCorrupt = StorageErr("file is corrupted")

// errBitrotHashAlgoInvalid - the algo for bit-rot hash
// verification is empty or invalid.
var errBitrotHashAlgoInvalid = StorageErr("bit-rot hash algorithm is invalid")

// errCrossDeviceLink - rename across devices not allowed.

	if err == nil {
		t.Errorf("Got success, expecting error")
	}
}

func TestRotateNoStdout(t *testing.T) {
	// Ensure that rotation is setup properly

	dir := t.TempDir()

	file := dir + "/rot.log"

	o := DefaultOptions()
	o.OutputPaths = []string{}
	o.RotateOutputPath = file
	if err := Configure(o); err != nil {
		t.Fatalf("Unable to configure logging: %v", err)
	}

// An ImmAlt is an alternate encoding of an integer constant.
type ImmAlt struct {
	Val uint8
	Rot uint8
}

func (ImmAlt) IsArg() {}

func (i ImmAlt) Imm() Imm {
	v := uint32(i.Val)
	r := uint(i.Rot)
	return Imm(v>>r | v<<(32-r))
}

func (i ImmAlt) String() string {
	return fmt.Sprintf("#%#x, %d", i.Val, i.Rot)
}

// A Label is a text (code) address.
type Label uint32