A method of managing a data storage medium. One portion of the medium is
reserved for storing data files and directories. Another, separate
portion of the medium is reserved for storing allocation information
related to the data in the first portion. Upon beginning a change of one
of the data files or directories in the first portion, that data file or
directory is flagged robustly until the change is completed. As needed,
for example when the medium is mounted on a host system, the incomplete
changes to the flagged data files and directories are undone or
completed.