case syscall.O_WRONLY:
		fallthrough
	case syscall.O_RDWR:
		fallthrough
	case syscall.O_WRONLY | syscall.O_CREAT:
		fallthrough
	case syscall.O_RDWR | syscall.O_CREAT:
		lockType |= syscall.LOCK_EX
	default:
		return nil, &os.PathError{
			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	f, err := os.OpenFile(path, flag|syscall.O_SYNC, perm)
	if err != nil {
		return nil, err
	}

const (
	offline = iota
	online
	closed
)

// NetworkError - error type in case of errors related to http/transport
// for ex. connection refused, connection reset, dns resolution failure etc.
// All errors returned by storage-rest-server (ex errFileNotFound, errDiskNotFound) are not considered to be network errors.
type NetworkError struct {
	Err error
}

func (n *NetworkError) Error() string {

}

func (e *Expression) aggregateRow(r Record, tableAlias string) error {
	for _, ex := range e.And {
		err := ex.aggregateRow(r, tableAlias)
		if err != nil {
			return err
		}
	}
	return nil
}

func (e *ListExpr) aggregateRow(r Record, tableAlias string) error {
	for _, ex := range e.Elements {
		err := ex.aggregateRow(r, tableAlias)
		if err != nil {
			return err
		}
	}
	return nil

			Path: path,
			Err:  syscall.EISDIR,
		}
	}

	return &LockedFile{File: f}, nil
}

// TryLockedOpenFile - tries a new write lock, functionality
// it is similar to LockedOpenFile with with syscall.LOCK_EX
// mode but along with syscall.LOCK_NB such that the function
// doesn't wait forever but instead returns if it cannot
// acquire a write lock.
func TryLockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {

	if len(e.And) == 1 {
		// In this case, result is not required to be boolean
		// type.
		return e.And[0].evalNode(r, tableAlias)
	}

	// Compute OR of conditions
	result := false
	for _, ex := range e.And {
		res, err := ex.evalNode(r, tableAlias)
		if err != nil {
			return nil, err
		}
		b, ok := res.ToBool()
		if !ok {
			return nil, errExpectedBool
		}
		if b {
			return FromBool(true), nil
		}

	w := NewWriter(b)
	inp := []byte("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.")

			p.err = errNestedAggregation
		}
	}
}

func (e *SelectExpression) analyze(s *Select) (result qProp) {
	if e.All {
		return qProp{isRowFunc: true}
	}

	for _, ex := range e.Expressions {
		result.combine(ex.analyze(s))
	}
	return
}

func (e *AliasedExpression) analyze(s *Select) qProp {
	return e.Expression.analyze(s)
}

func (e *Expression) analyze(s *Select) (result qProp) {

	lock, err := os.OpenFile(lockPath, os.O_CREATE|os.O_RDWR, 0666)
	if err != nil {
		return 0, err
	}
	defer lock.Close()
	if err := syscall.Flock(int(lock.Fd()), syscall.LOCK_EX); err != nil {
		return 0, err
	}

	// In case we're booting a device or emulator alongside all.bash, wait for
	// it to be ready. adb wait-for-device is not enough, we have to
	// wait for sys.boot_completed.

			Path: path,
			Err:  syscall.EISDIR,
		}
	}

	return &LockedFile{f}, nil
}

// TryLockedOpenFile - tries a new write lock, functionality
// it is similar to LockedOpenFile with with syscall.LOCK_EX
// mode but along with syscall.LOCK_NB such that the function
// doesn't wait forever but instead returns if it cannot
// acquire a write lock.
func TryLockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {

	lock, err = os.OpenFile(lockName, os.O_CREATE|os.O_RDONLY, 0666)
	if err != nil {
		return 1, err
	}
	if err := syscall.Flock(int(lock.Fd()), syscall.LOCK_EX); err != nil {
		return 1, err
	}

	if goarch := os.Getenv("GOARCH"); goarch == "arm64" {
		err = runOnDevice(appdir)
	} else {
		err = runOnSimulator(appdir)
	}
	if err != nil {