Linux file system composition

The Linux file system organizes files and directories to facilitate file management. a fixed directory structure has been created during installation. Each directory has its own purposes and files; level 1 ----------------------/-- (root directory) ----------- tree structure, directory tree has only one level 2 :... the Linux file system organizes files and directories to facilitate file management. a fixed directory structure has been created during installation. Each directory has its own purposes and files; level 1 ----------------------/-- (root directory) ----------- tree structure, directory tree has only one level 2: bin contains binary executable commands, the most basic system commands such as ls, kill, commands used by all users to complete basic maintenance tasks. Boot contains the core file used to start Linux. The grand unifiedbootloader (grub) multi-system boot manager (essentially a micro-system. you can choose to start the kernel in multiple operating systems at startup through chain startup); Linux kernel, vmlinuz is a bootable, compressed kernel; initrd. img (that is, boot load initial ram disk indicates that bootloader loads the initrd file in the storage medium to the memory, similar to win PE system, and can run without a hard disk; when the kernel starts, it first executes a file in the initrd file system, loads various modules (such as the file system storage media driver) to clear the obstacles, and then loads the real root partition on the physical disk, some embedded systems do not even need the real root, and initrd can do everything. similar winPE systems can be started without hard disks. In this way, the kernel vmlinuz can be smaller. it should not include drivers of all storage media. [Initrd. img details] dev contains all system device files, such as memory, modem, disk etc system and application configuration files, such as user name and password, rc. d. start the configuration file and script home to store ordinary users' personal files. lib contains the most basic shared link library and kernel module lost + found for storage in ext 2 or ext3 due to abnormal shutdown and fragments left by disk errors, the bootstrap will use the fsck program to discover these files. Each partition has a lost + foundmedia removable device mount point. The system will mount USB flash drives, CDs, and other devices to the location where mnt is temporarily used to mount the file system in this folder. for example, fat32 can be mounted, mount the device to be accessed. Most third-party software of opt will be installed in the virtual file system where proc exists in the memory by default, saving the status information of the kernel and process, such as cpuinfo saving cpu information. Root super user root's home directory, system administrator sbin super user root can use executable commands, system management commands, such as fsck, shutdown, reboottemp temporary file storage directory the usr system stores the program directory and user-level software, which is compared with the root directory of the storage system level. Almost all the files and applications to be used are here, such as commands, help files, and var to store dynamic program data, and some large file overflow areas, such as var/log to store system logs, var/locall application information and data. var/spool stores the offline data subdirectory of the program: usr/bin stores the routine application, usr/include: the header file usr/local required for the development and compilation of applications in Linux stores the usr/share Directory of the user's self-compiled and installed software, for example, font man helps usr/src kernel source code to store directories