I assume they are filing chapter 11. If so then the company will continue to operate while it restructures its debt. This will basically amount to finding a deal among the creditors restructure the debt. The shares will continue to trade for a while, and then, when the bankruptcy process is over the old shares will be cancelled. At that point the shareholders will lose 100% of their investment. (That's 100%, as in they won't receive one red cent.)
If the company emerges from bankruptcy as an operating company then the current creditors will be the new shareholders. However, in doing this the creditors will agree to write down or completely cancel the debt owed to them by Kodak.
There is also the possibility that the company will be liquidated. Liquidation could occur if it becomes apparent that there are no viable business prospects for the company. I think this is somewhat unlikely in this case, but not impossible, given the sorry state of the market for Kodak's products.
If there are any of you who are thinking of buying Kodak shares hoping to make money when the shares go up after the company emerges from bankruptcy you need to hear the and remember the following. If you buy and hold Kodak shares you will lose every last penny of your investment. There is virtually no chance that the current shares will have any value at the end of the bankruptcy proceedings. I repeat, you will lose every last penny if you hold your shares. The only possible chance for a shareholder to make money is to use the shares as betting chips, hoping to make money by buying and selling on the fluctuations of the share price. However, even this is, in general, a losing strategy because this kind of betting game is less then a zero sum game.