Linux basic Commands (i)

LS (list) command

 ls [ 选项 ]  <目录或文件位置>

Options :
-L: (long format) list displays the contents of the directory, showing permissions, time and other information
-A: Displays information for all subdirectories and files
-A: The function is basically the same as the-a option, "." "..." Two special hidden targets are not displayed
-D: Displays the properties of the directory itself and does not display content in the directory
-H: Displays the size of the directory or file in a more humane way, with the-l option
-R: Recursively displays all content in the specified directory and its subdirectories
Example :
ls -lA /etc/Long format displays all hidden files or directories under/etc/

ls -lh /etc/Display the information of all files and directories in the/etc/directory in a long-form user-friendly (unit from byte to k/m/g, etc.)

ls -lhd /etc/User-friendly display of/etc/directory information in long format

ls -R /etc/Recursively displays information about all files and subdirectories that are/etc/blind

Du (disk usage) command

 du  [ 选项 ]  <文件或目录的位置>

Used to count the size of the self-disk space occupied by a specified directory (or file)
Options :
-A: Statistical disk space consumption includes all files, not just the statistics directory
-H: Display results in a more user-friendly way (by default in kilobytes, but not in units)
-S: Only the total size of the occupied space is counted, and the size of each subdirectory and file is not counted.
Example :
du -sh /etc/Count the size of the/etc/directory

mkdir (make directory) command

 mkdir  [ 选项 ]   <目录位置及名称>

Options :
-P: Create nested multi-level catalogs at once
Example :
mkdir/hiahia///Create Hiahia under the root directory

Mkdir-p/data/hiahia///Create/data/directory and create/data/hiahia/directory in sequence

Touch command

 touch  <文件位置及名称>

Creates an empty file for testing, and when the directory already exists, updates the time stamp for the file
Example :
touch /tmp/hiahia.txtCreate a hiahia.txt empty file under the TMP directory

touch /tmp/{a..z}Create a new letter from A-Z in the/tmp/directory

CP command

 cp  [ 选项 ]  <源文件或目录>  <目标文件或目录>

Options :
-F: Override the target file or directory with the same name without a reminder and direct force replication
-I: Alert user when overwriting the target file or directory with the same name (Interactive, interactive)
-P: Preserve (Preserve) source file permissions, owner and time tags, and so on while copying
-r: This option must be used when copying directories, indicating that all files and subdirectories are replicated recursively
Example :
cp /etc/hosts /tmp/Copy the/etc/hosts file to the/tmp/directory

cp /etc/hosts /tmp/heheCopy the/etc/hosts file to the/tmp/directory and rename it to hehe file

cp -r /etc/ /tmp/Copy all contents of/etc/directory to/tmp directory;-r: Add-r option when copying directories

cp -p /etc/hosts.bak /tmp/Copy the/etc/hosts.bak file to the/tmp directory and save the original permissions

RM (remove) command

 rm  [ 选项 ]  <要删除的文件或目录>

Options :
-F: No reminders, direct force removal
-I: Remind users to confirm
-r: Recursively delete entire directory tree
Example :
Rm-f/tmp/hosts//Do not ask to forcibly delete/tmp/hosts files


rm-rf/tmp/etc///Do not ask to delete/tmp/etc/directory


* Note: "RM-RF/", command is extremely dangerous, do not try * *

MV Command

 mv  [ 选项 ]  <源文件或目录>  <目标文件或目录>

1. Transfer the established files or directories to the location
2. If the target location is the same as the original location, it is equivalent to performing a rename operation
Example :
mv /etc/hosts.bak /tmp/Move the/etc/hosts.bak file to the/tmp/directory and save the original file name

mv /etc/hosts.bak /tmp/heheMove the/etc/hosts.bak file to the/tmp/directory and change the name to hehe

mv /etc/hosts /etc/hosts.bakRename the/etc/hosts file to Hosts.bak

which command

 which  <命令>  |  <程序名> （ | 表示二选一）

Find the location of your Linux command program
1. The first target is found by default and no longer continues to find
2. If you are looking in all search paths, add the "-a" option
3. Unable to find the program file corresponding to the internal command
Example :
which lsSearch the full path of the LS command

which CD//search the full path of the CD command

Note : It is important to note that which can only search external commands during use.

Find command

 find  [ 查找范围 ]  [ 查找条件 ]

Fine-grained search for files or directories
Common search Criteria :
Find by name: "-name", wildcard "*", "?" Supported

Find by file size: "-size", can use "+", "-" as capacity conditions

Search by file owner: "-user"

Find by File type: "Type"

Example :
find /etc/ -name "host*"Search all files or directories under the/etc/directory that begin with host

find /etc/ -name "host?"Search all files or directories under the/etc/directory that begin with host

find /etc/ -size +1MSearch all files or directories larger than 1M in the/etc/directory

find /etc/ -size -1MSearch all files or directories less than 1M in the/etc/directory

find /boot/efi / -user rootSearch for all files or directories under the/boot/efi/directory that were created as root

find /etc/ -type dSearch all directories under the/etc/directory

logical operators :
? -A: and (and), show all the results of all conditions satisfied
? -O: or (or) to display results that meet one of the conditions
find / -type d -a -name vm*Search/Lower directory and start with a directory named VM

find / -type d -o -name vm*Search/Next Directory or/bottom file or directory starting with VM

Linux basic Commands (i)