CSE 411 Filesystems

File Types

Types of files in a filesystem, including regular files, directories, symbolic links, FIFOs, sockets, and device files.

File Permissions

Access rights for files, represented as rwx for read, write, and execute, assigned to owner, group, and others.

Hard Links

Links that cannot span filesystems and share the same inode.

Symbolic Links

Links that can span filesystems and are created using the command ln -s.

Directories

Special folders in a filesystem that organize files, such as /etc, /home, /var, /usr, and /tmp.

Character Special Files

Device files allowing raw device access without buffering.

Block Special Files

Device files that provide buffered access to a device.

Fake Filesystems

Filesystems created at boot time, such as /proc.

Disk Components

Elements of a disk, including platters, cylinders, tracks, and sectors.

Partitions

Sections of a disk divided into cylinders, managed with tools like fdisk or gdisk.

GPT

Modern, flexible partition scheme

Superblock

Contains metadata about the filesystem, including block size and free blocks.

Inodes

Data structures that track file attributes, locations, and permissions in UNIX filesystems.

Cylinder Groups

Optimize file storage and hold data blocks, inode blocks, and filesystem metadata.

Mounting

Process of attaching a filesystem to a directory, tracked in /etc/fstab.

Unmounting

The process of detaching a filesystem, requiring no active file use, done with umount.

fsck

Command used to check the integrity of a filesystem.

df

Command used to display disk usage.

Device Numbers

Major and minor numbers used to identify device drivers and modify their behavior.

MBR

Legacy partitioning structure.