A transactional file system developed to function with flash memory is described. The file system performs power-failure detection and ensures data integrity in the event of a power failure. In one described implementation, a power failure event can be detected by a file system, components of the file system, or individual modules in the form or computer-executable instructions and/or logic. Meta-information is stored at a location on a flash medium indicated by a write pointer if a computer device shuts-down according to a normal shutdown mode. During initialization of the computer, a check is performed whether the meta-information is present in the location on the flash medium indicated by the write pointer. If the meta-information is present, then a conclusion is made that the computer shutdown according to the normal shutdown mode.