Transaction-safe FAT files system

In one aspect, the present disclosure describes a process for maintaining file allocation tables (FATs) for a volume of storage medium. The process includes triggering, by a write operation, modification of data in an existing sector of a data file by writing of data to a new sector of the storage medium. The process also includes writing revised used/unused sector information into one FAT and setting a variable indicative of a number of FATs (NOF) to a first value. The process additionally includes copying the one FAT to another FAT and re-setting the variable to a second value.