SharePoint - How to retrieve from or save data in SharePoint Lib programatically?

Hi,

  I am using SharePoint 2010. In SharePoint site there is a Form Library which has column "Current Date". I want to create a timer job which will update this column with current system date once in a day. 
  I know this is possible with SharePoint list with following code:
================================================================
            SPList shippingList = oSPWeb.Lists["Candidate Info"];
                    SPQuery listQuery = new SPQuery();
                    listQuery.Query = "<Where><IsNotNull><FieldRef Name='Title' /></IsNotNull></Where>";

                    SPListItemCollection Items = shippingList.GetItems(listQuery);

                    if (Items.Count > 0)
                    {
                        foreach (SPListItem item in Items)
                        {
                            SPListItem itemToUpdate = shippingList.GetItemById(item.ID);

                            itemToUpdate["Current Date"] = DateTime.Now;
                            itemToUpdate.Update();
                         }
                }  ================================================================
  But this code is not working with me for SP Form Library. Is anything missing in above code, or is any other way to achieve the above requirement.