Transaction-Safe FAT File System: Difference between revisions

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== TFAT ==

In addition, TFAT only can be implemented in a system using the extended FAT ([[exFAT]]) file system. TFAT supported by an exFAT file system is also known as [[TexFAT]].

The original form of TFAT was a driver layer modification to the original [[FAT]] file system that maintained two copies (FAT0 and FAT1) of the file allocation table instead of just one. While performing a drive operation, changes would be made to FAT1. When the operation was complete, the FAT1 table would be copied to FAT0, updating the stable view of the file system.<ref name=MSTFAT>[http://msdn.microsoft.com/en-us/library/aa915463.aspx TFAT Overview]</ref>

== TexFAT ==

The '''Transaction-Safe Extended FAT File System''' (TexFAT), TexFAT provides similar functionality to the original TFAT using the [[exFAT]] file system as the base file system instead of FAT. Introduced with [[Windows Embedded CE 6.0]], it replaced TFAT, and is frequently referred to as TFAT, which can lead to confusion with the original TFAT described above.<ref name=MSTexFAT>[http://msdn.microsoft.com/en-us/library/cc907927.aspx Transaction-Safe Extended FAT File System]</ref>

The use of exFAT as the underlying file system allows for larger files and larger partitions. TexFAT requires a hardware-specific driver designed for the type of media on which the TexFAT volume resides.<ref name=MSTexFAT />

== Limitations ==

Due to the lack of support in desktop [[operating system]]s, both forms of TFAT are not recommended for removable media. While the desktop OS could still read the drive, it could not use the transaction-safe features, so unexpected removal or a power outage could lead to data loss. In addition, directories created under the desktop OS may not be transaction-safe even if the drive is later attached to a TFAT aware OS.<ref name=MSTFAT />

== References ==

{{reflist|2}}

==External links==

* [http://msdn.microsoft.com/en-us/library/aa911939.aspx Transaction-Safe FAT File System]

* [http://msdn.microsoft.com/en-us/library/aa915463.aspx TFAT Overview]

[[Category:Windows disk file systems]]

[[Category:Flash file systems]]