How do we make sure that the hard disk integrity is maintained during power failures?
The DOS, EXT2, and QNX 4 filesystems aren't currently power-safe. Therefore file or partition corruption on a hard drive could occur during power failures. However a number of measures can be implemented to try to reduce the amount of eventual HDD corruption.
The Power-Safe (fs-qnx6.so) filesystem uses a copy-on-write (COW) technique to always maintain an uncorrupted version of the filesystem, even if a power failure occurs. For more information, see the Filesystems chapter of the System Architecture guide.
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