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Chapter 11

Chapter 11 explores how operating systems organize, store, and access data through files, file systems, and directories. A file is a named collection of data, while the file system provides the OS’s logical view of how those files are managed. The chapter explains the difference between text files—interpreted as ASCII or Unicode characters—and binary files, which store data in specialized formats. File types and extensions help users and software identify how to interpret file contents. The chapter also covers basic file operations, including creating, reading, writing, and deleting files. Two access methods are introduced: sequential access, where data is read linearly, and direct access, which retrieves records by their logical number. Next, file protection is discussed, including UNIX permission categories for controlling who may read, write, or execute a file. Directory structures are presented through directory trees, parent and subdirectories, working directories, and absolute versus relative paths. Finally, the chapter explains disk scheduling algorithms—FCFS, SSTF, and SCAN—which help optimize the order of servicing disk access requests for efficiency. Provide your feedback on BizChat