Linux Self-Study notes (6): Linux file system and file types

File systems for Linux:
With file system (ROOTFS)
Root filesystem

Lsb,fhs:linux Release Standard
1 bin Boot Dev etc home lib lib64 media mnt opt proc root run sbin SRV sys tmp usr var

/boot: Boot file directory, kernel file (vmlinuz), boot loader (bootloader,grub)
/bin: A basic command for all users, a program that cannot be associated with a separate partition, and that is used by OS startup;
/sbin: The basic command of the management class, cannot associate the independent partition, the OS starts to use the program;
/lib: Basic shared library files and kernel module files (/lib/mudules)
/LIB64: The storage location of auxiliary shared files on dedicated and x86_64 systems;
/etc: Configuration file directory (plain text file)
/home/username: General user home directory;
/root: Administrator home directory;
/media: Mount Portable mobile device mount points such as: U disk, CD
/MNT: Temporary file system mount points such as: hard disk
/dev: storage location for device files and special files
/OPT: Third-party application installation location;
/SRV: Data used by services running on the system;
/RMP: Temporary file storage
/usr:universal GKFX, read-only data;

Bin: An application that ensures that the system has full functionality;
Sbin: Ibid.
Lib: ibid.
Lib64: Ibid.
Include:c header file for the program (header files)
Share: structured independent data, such as Doc,man
Local: Installation location for third-party applications (Bin,sbin,lib,lib64,etc,share)

/var/:variable Data files
Cache: Application Caching directory
LIB: status information for an application
Local: Applications that are dedicated to/usr/local/store mutable files
Lock: Lock file
LOG: Logs directory and files
OPT: variable data that is dedicated to application storage under/OPT
Run: Data related to a running process, usually used to store a process's PID file;
Spool: Buffer pool
TMP: Temporary data generated during system restart
/proc: Used to output kernel-to-process-related virtual file systems
/sys: Virtual file system for outputting information about hardware devices on the current system
/misc: Miscellaneous
/selinux:security enhanced Linux,selinux related security policies and other information storage location;

Components of an application on Linux:
Binary program:/bin,/sbin,/usr/sbin,/usr/local/bin,/usr/local/sbin
Library files:/lib,/lib64,/usr/lib,/usr/lib64,/usr/local/lib,/usr/local/lib64
Configuration file:/etc,/etc/directory,/usr/local/etc
Help file:/usr/share/man,/usr/share/doc,/usr/local/share/man,/usr/local/share/dec
File types under Linux:
-(f): Ordinary documents
D: Catalog file
B: Block device
C: Character device
L: Soft connection, Symbolic connection file
P: Pipeline File
S: socket file; socket;

System Management Class Commands:
Shutdown
Halt,init 0,shutdown-p,poweroff
Restart

Init 6
Reboot
-F: Force shutdown, do not call shutdown
-P: Power off and off
Shutdown: Shutting down the system
Overview Synopsis
/sbin/shutdown [-t sec] [-ARKHNCFF] time [warning-message]
Time
Now: Turn off the machine immediately
+m: Relative time rule: +3 means shutting down the system after 3 minutes
HH:MM: Absolute Time: The name of the system time

User login Information View command:
Whoaml: Displays the active user who is currently logged on
Wh0: Displays the current system logon session
W: Detailed current system logon session

Linux Self-Study notes (6): Linux file system and file types