First thing on the command line: CD ~

Main content: add, delete, change and check

Search: View a file or directory

View the absolute path of the current directory

• PWD (CD ~/desktop/ can change the current path to the desktop)

View the current directory

• ls

View the contents of a specified directory

• Ls path

Viewing file Contents

• Cat path (show all)
• Head path (to show the first ten lines, use [space +-n+ space + desired number of lines, such as -n 14] to see the desired number of lines)
• Tail path (to show the last ten lines, use [space +-n+ space + desired number of lines, such as -n 14] to see the desired number of lines)
• Less path (only part of the path is displayed, that is, split screen, press the arrow key to scroll, Q exit)

Add: Create a file

Create a file

• touch 1.txt
• Echo hi>1.txt
• Echo hi>>1.txt
• Echo -e “1\n2”>1.txt

Create multiple files

• touch 1.txt 2.txt

Create a file

• Mkdir a(create a folder in current directory)
• Mkdir -p a/b/c(create a/b/c folder in the current directory with -p as parameter)

Create multiple directories

• mkdir -p a/b/c a/d/c

Copy the file

• cp 1.txt 2.txt

Copy directory

• Cp -r a b (-r means recursive, must add -r to copy directory)

Delete: Deletes a file

• rm 1.txt
• rm -r a
• Rm -rf a(f stands for force, forcibly deleted)

Modify: Modify a file or directory

Modify or append file contents

• Echo hi>1.txt
• Echo hi>>1.txt

Empty file

• Echo “>1.txt (place empty string in 1.txt)
• Code 1.txt (select all delete code after opening the file)

Move files/directories

• Mv 1.txt a (put 1.txt into a folder)
• Mv a/1.txt. (Put 1. TXT in a into the current directory, which is abbreviated as.)

Renames files/directories

• Mv 1.txt 2.txt (rename 1.txt to 2.txt)

Change the last update time of a file

• Ls-1 View the update time of a file