File System
A file system gives the operating system a reliable way to name, store, retrieve, share and protect information on secondary storage. Work through the unit in the order a real file travels: from an application, into a directory, across disk blocks, and back again.
A file system is the set of data structures, rules and operating-system services that organise files on a storage device. It turns raw blocks into meaningful names such as notes.txt, remembers where each file lives, and checks whether a process is allowed to use it.
Real-world analogy: A library catalogue
Select a file or create a draft, then watch how an operating system coordinates the application, file record and disk blocks.
Application
open · read · write · close
File control table
name · owner · size · block pointers
Disk blocks
data and free-space map
/home/student
System event
The file system is ready for an operation.
Attributes
Name, identifier, type, location, size, protection, owner and creation or modification times.
Operations
Create, open, read, write, seek, close, rename and delete. The OS validates each request.
Access methods
Sequential reads in order; direct jumps to a block; indexed uses an index to find records quickly.
1. Which structure maps a human-readable file name to its file record?
2. Which access method jumps directly to a known position?