Inside The File System

Figure 12.1 shows that the physical disk is divided up into partitions:

Figure 12.1  Partitions


Figure 12.2 shows an idealized Unix file system on a particular partition. HFS+ is actually implemented differently, but this mental model will help you understand the upcoming system calls.

Figure 12.2  Filesystem


The superblock is a block in a known location that has pointers to the rest of the on-disk data structures. Frequently there are redundant copies of the superblock in case the primary superblock gets destroyed.

An inode, ...

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