Summary of common commands for Linux systems (i) File and directory operations

Files and directories
	Command	Options	Annotations	Example
Basic operation of the file	Ls	Options File	Show All files and directories	Ls-al
		-A (a)	Displays all files and directories, including hidden files and directories (showing all files and directories, including hidden files and directories, but not realistic "." and ".." Directory	View details of all files in the current directory =ll
		-L	Display full attribute information for files and directories
		-D
	Cd	+ Path	Change the current path	Cd/etc go to the ETC directory
	Pwd		Show current Path	PWD Displays the current path
	Mkdir	+ Directory Name	Create a Directory	MKDIR ABC create ABC directory
		-P	Parent directory is created when parent directory does not exist
	RmDir	+ Directory Name	Delete directory, only empty directory can be deleted	RMDIR ABC delete ABC directory
	Cp	[Options] Source target	Copying files	Cp-r test/usr/Copy all content in the test directory under the current directory, including subdirectories, to the USR directory
		-R	Looping for directory replication
		-F
	Mv	SOURCE Target		MV test/usr/move the test directory under the current directory to the USR directory
	Rm	[Options] File name	Delete	RM-RF test forcibly deletes the test directory under the current directory and all its files and subdirectories
		-R	Cyclic deletion, commonly used for directory deletion, to delete all files in directories and directories
		-F	Force Delete Does not prompt
View File Contents	Cat	[Options] File name	View File Contents	Cat-nb/etc/inittab Displays the contents of the Inittab file in the ETC directory, displaying line numbers but not showing blank lines
		-N	Display with the Lianxing number
		-B	Lianxing display, but no blank lines are displayed
	More	+ File name	With cat, if the file content more than 40 lines, will be split screen display, press ENTER single line down or press ctrl+f page, press Q exit browse	Usage with Cat
	Head (tail)	[Options] File name	Show file before (after) 10 lines	head-5/test
		-N	Specify how many rows to display	Displays the first 5 lines of the test file in the current directory
	Cut	options [File]	Select a portion of each line in the file to display	Cut–d ":" –f 2 c.txt
		-D	To use (...). ) to split	To: Split c.txt each row, showing the second column of each row in the C.txt document
		-F	Show the first few columns
Link file	ln	[Options] Source target	Set the link file to create a hard link by default when the parameter is empty	ln (-D) ct.sh DLink
		-S	Creating Symbolic Links	Create a DLink hard link in the current directory, point to Ct.sh
		-D	Create a hard link
Search for files and directories	Find	Path [Options] File name	You can specify a directory and all subdirectories to search because it is slower to find the hard disk	Find. –name "*.txt" –atime 1
		-name file	Find file named name file, wildcards available *	Find A. txt file accessed within one hours of the current directory
	Locate	+ File name	Find from established database, very fast, but database content needs to be updated in real time, database can be updated manually by UpdateDB command	Usage with find
	which	+ File name	Find the location of the executable file by the path under environment variable path	which LS
	Whereis	[Options] File name	Search based on a set directory, not a directory under path but a custom directory	Whereis ls
		-B	Find only binary files
		-M	Just find the documentation.
	Grep	Option pattern (included string) file name	Indicates that the line containing the specified content is found in the text file	Grep–n 456 B.txt
		-N	Show line Numbers	Show line numbers in B.txt that contain 456
		-I.	String is case-insensitive	Grep–v 456 B.txt
		-V	Reverse, indicating that a line with no specified content is found in a text file	Show rows that do not contain 456 in B.txt
File and Directory Permissions	Chown	[Options] User:group directory or file name	Change the owner and owning group of a file or directory	Chown-r Lucy:root Lamp
		-R	All files under the directory are changed	Change the lamp directory under the current directory and the owner of all files and subdirectories files to Lucy, and the owning group to root
	chmod	Options [Parameters] Directory or file name	Change read and write execution permissions for a file or directory	1.chmod 760 ct.sh Change the permissions of the ct.sh file under the current directory to RWXRW----
		-R	All files under the directory are changed	2.chmod ug=rwx,o=r ct.sh Change the permissions of the ct.sh file under the current directory to rwxrwxr--
				3.chmod g-r,o+w ct.sh Remove the Read permission for the group that belongs to the ct.sh file in the current directory, and add write permission to other people

Summary of COMMON commands for Linux systems (i) file and directory operations