I recently had to deal with some hard drive corruption issues – sad story – and along the road to recovery stumbled upon Rod Smith’s GPT fdisk Tutorial, an incredibly useful list of information and links to various tools for all things GPT:

GPT fdisk (consisting of the gdisk, cgdisk, sgdisk, and fixparts programs) is a set of text-mode partitioning tools for Linux, FreeBSD, Mac OS X, and Windows. The gdisk, cgdisk, and sgdisk programs work on Globally Unique Identifier (GUID) Partition Table (GPT) disks, rather than on the older (and once more common) Master Boot Record (MBR) partition tables. The fixparts program repairs certain types of damage to MBR disks and enables changing partition types from primary to logical and vice-versa. You can learn more about fixparts on its dedicated Web page. If gdisk, cgdisk, and sgdisk sound interesting to you, then read on (or skip straight to the “Obtaining GPT fdisk” link if you don’t need the GPT pep talk). If you don’t know what a GPT is, be sure to read the first section!

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