Abstract: A method for handling a file system write to a media during execution of a software utility for the media wherein the software utility reads at least one file structure from the media and storing the file structure into a local copy of the file structure. A write monitor driver routine detects the file system write to the media and logs a set of parameters for the file system write. The software utility retrieves the log and determines whether the parameters indicate that the file system write affects the local copy of the file structure and whether a restart is required.

Abstract: A file defragmentation utility for a computer system is disclosed that enables multithreaded preemptive multi-tasking during file defragmentation. The utility includes a defragmentor routine that defragments clusters or portions of a file on a storage media and then updates one or more file system structures to indicate the new locations of the defragmented clusters of the file. An alias driver is provided that traps accesses to the file and that maintains coherent access to the file while the file system structures are updated.

Abstract: A method for compressing FAT and FAT-like structures, which include runs of primitives and runs intervening codes, includes the steps of receiving a plurality of primitive runs in a memory and generating a plurality of variable-length code sequences where each code sequence is dedicated to a primitive run. Each code sequence indicates of its dedicated run, a primitive-type, a primitive runlength, the presence of an intervening run and, if present, an intervening runlength, and the presence of a jump value pointer. If a jump value pointer is present, the code sequence further indicates the jumplength, which is indicated as a difference (or .alpha.) value. The length of each code sequence varies depending on run characteristics such as primitive runlength, intervening runlengths and jumplength.