FAT

Creating a virtual disk

dd if=/dev/zero of=ramdisk.img count=30000
fdisk ramdisk.img

Press [n, ENTER, ENTER, ENTER, t, 6, w]

mkfs.fat --offset 2048 ramdisk.img

File Allocation Table (FAT)

  • If the file size is larger than the sector size, file data is spanning over multiple sectors in the cluster.
  • If the file size is larger than the cluster size, file data is spanning over multiple clusters in the cluster chain.

On entries in the FAT

  • Directory contents (data) are a series of 32 byte directory entries.
  • Value of the entry is the cluster number of the next cluster following this corresponding cluster.

Inode

The inode is a data structure in a Unix-style file system that describes a file-system object such as a file or a directory. Each inode stores the attributes and disk block locations of the object's data.

References