The disk hardware presents a generic interface
Each block of data has a number (or three)
Asking for data block 19686144 is no fun
One of the jobs of the OS is to provide files
Named collections of data
When you ask for file /usr/local/apache/logs/access_log, how does it know which data blocks hold the data?
The filesystem (FS) provides this index
Also permissions, directory structure, etc.
Filesystem operations include:
open read write link unlink rename symlink readlink chmod chown stat truncate