help command
man man ls
help Get help information for viewing shell built-in commands (cd)
Commonly used convenience
ctrl+c to stop the process
ctrl+l clear screen (clear) completely clear screen (reset)
file directory class
pwd : display the absolute path
ls [Options]: Display all directory contents under the current file
Options: -a all files including hidden files
-l long data list (equivalent to ll)
cd path: switch paths
mkdir [option] filename: create a new folder
Option: -p can create multi-level directories
rmdir filename: delete an empty folder
touch filename: create an empty file
cp [option] original file destination file: copy file operation
Options: -r copy entire folder recursively
rm [option] filename: delete file
Option: -r deletes all contents of the directory recursively
-f force delete operation
-v displays the detailed execution process of the command
mv old new : move files or rename them
cat view file
more View the file: [space bar: turn down one page] [enter: next line]
【q to leave】 【B to return to the previous screen】
less View files: / string (downward to find the specified string)? substring (look up for the specified string)
echo: output content to the console
head [option]: display the information of the file header
Options: -n 5 display 5 lines
tail [option]: display the information at the end of the file
Options: -f Track all updates to this document in real time
output redirection > append >>
1) ls -al > file: write the content in the list to the file (overwriting)
echo content >> file Append content to file
soft link
Establish a soft connection: ln -s turns out to be now
Delete soft connection: rm -rf soft connection name rm -rf soft connection name/[The real file directory will also be deleted]
history View historical commands
date displays the current time
date +%Y%m%d display year, month, day %H %M %S hour minute second
date -d '1 days ago': display the time of the previous day
date -d '-1 days ago' : display tomorrow's time
set system time
date -s "Standard format of time YY-MM-dd hh:mm:ss"
cal view calendar