How to know what filesystem is on my ubuntu and whether dir_index is enabled?

[Peng Yu]

On Tue, Jan 26, 2010 at 12:52 AM, Karl F. Larsen <klarsen1 at gmail.com> wrote:
> Peng Yu wrote:
>> Could somebody let me know how to figure out what filesystem is on my
>> ubuntu machine? And how to check whether dir_index is enabled?
>>
>        Boot up in your liveCD and with Partition Editor display your
> hard drive(s). Then if all looks good check the desired
> partition with fdisk. It can replace your dir_index if needed.

What if I can not reboot the machine?