buf := make([]byte, 1)
	if _, err := b.Read(nil); err != nil {
		t.Fatalf("1st nil Read = %v; want nil", err)
	}
	if _, err := b.Read(buf); err != errFake {
		t.Fatalf("1st Read = %v; want errFake", err)
	}
	if _, err := b.Read(nil); err != nil {
		t.Fatalf("2nd nil Read = %v; want nil", err)
	}
	if _, err := b.Read(buf); err != nil {
		t.Fatalf("3rd Read with buffer = %v; want nil", err)
	}

}

var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")

// UnreadByte unreads the last byte returned by the most recent successful
// read operation that read at least one byte. If a write has happened since
// the last read, if the last read returned an error, or if the read read zero
// bytes, UnreadByte returns an error.
func (b *Buffer) UnreadByte() error {

	closed   bool
}

func (pr *progressReader) Read(p []byte) (n int, err error) {
	// This ensures that Close will block until Read has completed.
	// This allows another goroutine to close the reader.
	pr.closedMu.Lock()
	defer pr.closedMu.Unlock()
	if pr.closed {
		return 0, errors.New("progressReader: read after Close")
	}
	return pr.processedReader.Read(p)
}

func (pr *progressReader) Close() error {

		defer deadlineconn.Close()

		// Read a line
		b := make([]byte, 12)
		_, terr = deadlineconn.Read(b)
		if terr != nil {
			t.Errorf("failed to read from client. %v", terr)
			return
		}
		received := string(b)
		if received != "message one\n" {
			t.Errorf(`server: expected: "message one\n", got: %v`, received)
			return
		}

		// Wait for more than read timeout to simulate processing.

// the upstream reader after close has been called.
type disconnectReader struct {
	r  io.Reader
	mu sync.Mutex
}

func (d *disconnectReader) Read(p []byte) (n int, err error) {
	d.mu.Lock()
	defer d.mu.Unlock()
	if d.r != nil {
		return d.r.Read(p)
	}
	return 0, errors.New("reader closed")
}

func (d *disconnectReader) Close() error {
	d.mu.Lock()
	d.r = nil
	d.mu.Unlock()
	return nil

}

// Unlock - block until write lock is released.
func (di *distLockInstance) Unlock(lc LockContext) {
	if lc.cancel != nil {
		lc.cancel()
	}
	di.rwMutex.Unlock(lc.ctx)
}

// RLock - block until read lock is taken or timeout has occurred.
func (di *distLockInstance) GetRLock(ctx context.Context, timeout *dynamicTimeout) (LockContext, error) {
	lockSource := getSource(2)
	start := UTCNow()

	// check not at EOF
	b.WriteString("abcdefghijklmnopqrstuvwxyz")

	// after unsuccessful read
	if n, err := b.Read(nil); n != 0 || err != nil {
		t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
	}
	if err := b.UnreadByte(); err == nil {
		t.Fatal("UnreadByte after Read(nil): got no error")
	}

	// after successful read
	if _, err := b.ReadBytes('m'); err != nil {
		t.Fatalf("ReadBytes: %v", err)
	}

	if err != nil {
		return "", fmt.Errorf("network id: %v", err)
	}
	fs, err := procfs.NewFS("/host/proc")
	if err != nil {
		return "", fmt.Errorf("read procfs: %v", err)
	}
	procs, err := fs.AllProcs()
	if err != nil {
		return "", fmt.Errorf("read procs: %v", err)
	}
	oldest := uint64(math.MaxUint64)
	best := ""

	isReadLock := false
	return dm.lockBlocking(ctx, cancel, id, source, isReadLock, opts)
}

// RLock holds a read lock on dm.
//
// If one or more read locks are already in use, it will grant another lock.
// Otherwise the calling go routine blocks until the mutex is available.
func (dm *DRWMutex) RLock(id, source string) {
	isReadLock := true

	"bytes"
	"fmt"
	"io"
	"net/http"
	"strings"
)

// newUnsignedV4ChunkedReader returns a new s3UnsignedChunkedReader that translates the data read from r
// out of HTTP "chunked" format before returning it.
// The s3ChunkedReader returns io.EOF when the final 0-length chunk is read.
func newUnsignedV4ChunkedReader(req *http.Request, trailer bool) (io.ReadCloser, APIErrorCode) {
	if trailer {
		// Discard anything unsigned.