Command |
Function Description |
Online query and help commands (2) |
Man |
View Command help, command dictionary, more complex info, but not commonly used. |
Help |
View the help of Linux built-in commands, such as the cd command. |
File and directory operation commands (18) |
Ls |
The full list function is to list the contents of a directory and its content attributes. |
Cd |
The change directory function is to switch from the current working directory to the specified working directory. |
Cp |
The full copy function is to copy files or directories. |
Find |
It is used to find the Directory and files in the directory. |
Mkdir |
Make directories. Its function is to create a directory. |
Mv |
The function of moving all files is to move or rename files. |
Pwd |
Print working directory, which is used to display the absolute path of the current working directory. |
Rename |
Used to rename a file. |
Rm |
Remove all files or directories. |
Rmdir |
Remove empty directories to delete empty directories. |
Touch |
Create a new empty file and change the timestamp attribute of the existing file. |
Tree |
The function is to display contents in a directory in a tree structure. |
Basename |
Displays the file name or directory name. |
Dirname |
Displays the file or directory path. |
Chattr |
Change the extension attributes of a file. |
Lsattr |
View the file extension attributes. |
File |
The type of the displayed file. |
Md5sum |
Calculate and verify the MD5 value of the file. |
View File and content processing commands (21) |
Cat |
Concatenate is used to connect multiple files and print them to the screen output or redirect them to the specified file. |
Tac |
Tac is the reverse spelling of cat, so the command function is to reverse display the file content. |
More |
The file content is displayed by page. |
Less |
The file content is displayed by page. The more command is used in reverse mode. |
Head |
Displays the File Content Header. |
Tail |
The end of the file. |
Cut |
Splits and outputs each line of the file according to the specified delimiter. |
Split |
Split the file into different small fragments. |
Paste |
Merge file content by line. |
Sort |
Sorts the text content of a file. |
Uniq |
Remove duplicate rows. Oldboy |
Wc |
Count the number of lines, words, or bytes of the file. |
Iconv |
The encoding format of the converted file. |
Dos2unix |
Converts a DOS file to a UNIX file. |
Diff |
Difference is used to compare differences between files. |
Vimdiff |
Command Line visual file comparison tool, commonly used in text files. |
Rev |
Reverse output file content. |
Grep/egrep |
Filter string. |
Join |
Merge by the same fields of the two files. |
Tr |
Replace or delete characters. |
Vi/vim |
Command Line Text Editor. |
File compression and decompression commands (4) |
Tar |
Package and compress. Oldboy |
Unzip |
Decompress the file. |
Gzip |
Gzip compression tool. |
Zip |
Compression tool. |
Information Display command (11) |
Uname |
Command Used to display information about the operating system. |
Hostname |
Displays or sets the Host Name of the current system. |
Dmesg |
Displays the boot information to diagnose system faults. |
Uptime |
Displays the system running time and load. |
Stat |
Displays the status of a file or file system. |
Du |
Calculate disk space usage. |
Df |
Reports disk space usage of the file system. |
Top |
Displays system resource usage in real time. |
Free |
View the system memory. |
Date |
Display and set the system time. |
Cal |
View calendar and other time information. |
Search file commands (4) |
Which |
Find binary commands and search by PATH of the environment variable. |
Find |
Search for files or directories through disk traversal. |
Whereis |
Find binary commands and search by PATH of the environment variable. |
Locate |
Run the/var/lib/mlocate. db command to update the database. |
User management command (10) Old Boy |
Useradd |
Add a user. |
Usermod |
Modify existing user attributes of the system. |
Userdel |
Delete a user. |
Groupadd |
Add user groups. |
Passwd |
Change the user password. |
Chage |
Change the validity period of the user password. |
Id |
View the uid, gid, and user group of the user. |
Su |
Switch user identity. |
Mongodo |
Edit exclusive commands for the/etc/sudoers file. |
Sudo |
Execute commands allowed in the sudoers file as another user (Default root User. |
Basic network operation commands (11) Old Boy |
Telnet |
Use TELNET to log on remotely. |
Ssh |
Use SSH encryption protocol for remote logon. |
Scp |
Complete secure copy, used to copy files between different hosts. |
Wget |
Download the file through the command line. |
Ping |
Test the network connectivity between hosts. |
Route |
Displays and sets the route table of a linux system. |
Ifconfig |
Command for viewing, configuring, enabling, or disabling network interfaces. |
Ifup |
Start the NIC. |
Ifdown |
Disable the NIC. |
Netstat |
View the network status. |
Ss |
View the network status. |
In-depth network operation commands (9) |
Nmap |
Network scan command. |
Lsof |
Full name list open files, that is, list files already opened in the system. |
Mail |
Send and receive emails. |
Mutt |
Mail management commands. |
Nslookup |
Interactive Query of Internet DNS commands. |
Dig |
Find the DNS resolution process. |
Host |
Query DNS commands. |
Traceroute |
Tracks the Route status of data transmission. |
Tcpdump |
Command Line packet capture tool. |
Commands for disks and file systems (16) |
Mount |
Mount the file system. |
Umount |
Uninstall the file system. |
Fsck |
Check and fix the Linux File System. |
Dd |
Convert or copy files. |
Dumpe2fs |
Export ext2/ext3/ext4 file system information. |
Dump |
Ext2/3/4 file system backup tool. |
Fdisk |
Disk Partition command, applicable to disk partitions under 2 TB. |
Parted |
The disk partition command does not limit the disk size. It is usually used for disks smaller than 2 TB. |
Mkfs |
Format and create a Linux File System. |
Partprobe |
Update the information of the hard disk partition table of the kernel. |
E2fsck |
Check the ext2/ext3/ext4 file system. |
Mkswap |
Create a Linux swap partition. |
Swapon |
Enable swap partition. |
Swapoff |
Disable swap partition. |
Sync |
Write Data in the memory buffer to the disk. |
Resize2fs |
Adjust the size of the ext2/ext3/ext4 file system. |
System permissions and user authorization commands (4) |
Chmod |
Change the file or directory permissions. |
Chown |
Changes the owner and group of files or directories. |
Chgrp |
Change the file user group. |
Umask |
Display or set the permission mask. |
Command for viewing system user login information (7) |
Whoami |
A valid user name is displayed, which is equivalent to executing the id-un Command. |
Who |
Displays the user information of the current logon system. |
W |
Displays the list of users that have logged on to the system and the commands that the user is executing. |
Last |
Displays the users logged on to the system. |
Lastlog |
Displays the last logon information of all users in the system. |
Users |
Displays the list of all users currently logged on to the system. |
Finger |
Search for and display user information. |
Built-in commands and others (19) |
Echo |
Print the variable or directly output the specified string |
Printf |
Format the result and output it to the standard output. |
Rpm |
Command for managing rpm packages. |
Yum |
Automate and simplify the command for managing rpm packages. |
Watch |
Periodically execute the given command and display the command output in full screen mode. |
Alias |
Set the system alias. |
Unalias |
Cancels the system alias. |
Date |
View or set the system time. |
Clear |
Clear the screen. |
History |
View the command execution history. |
Eject |
The optical drive is displayed. |
Time |
Calculates the command execution time. |
Nc |
Powerful network tools. |
Xargs |
Converts a standard input to a command line parameter. |
Exec |
The command that calls and executes commands. |
Export |
Set or display environment variables. |
Unset |
Delete a variable or function. |
Type |
Used to determine whether another command is a built-in command. |
Bc |
Command Line scientific calculator |
System management and performance monitoring commands (9) |
Chkconfig |
Manage Linux boot items. |
Vmstat |
Virtual Memory statistics. |
Mpstat |
Displays the status statistics of each available CPU. |
Iostat |
Statistics System IO. |
Sar |
Obtain performance data of the system, including CPU, Operation queue, disk I/O, paging (SWAP zone), memory, CPU interruption, and network. |
Ipcs |
Used to report the status of inter-process communication facilities in Linux. The displayed information includes the message list, shared memory, and semaphore information. |
Ipcrm |
Deletes one or more message queues, semaphore sets, or shared memory IDs. |
Strace |
Used to diagnose and debug the Linux user space tracker. We use it to monitor the interaction between user space processes and the kernel, such as system calls, signal transmission, and process status changes. |
Ltrace |
The command will trace the library function call of the process, and it will show which library function is called. |
Command for shutdown/restart/logout and Viewing System Information (6) |
Shutdown |
Shut down. |
Halt |
Shut down. |
Poweroff |
Power off. |
Logout |
Exit the Shell that is currently logged on. |
Exit |
Exit the Shell that is currently logged on. |
Ctrl + d |
The shortcut for exiting the currently logged-on Shell. |
Process Management commands (15) |
Bg |
Change a command that is paused in the background to continue (executed in the background ). |
Fg |
Move the commands in the background to the foreground to continue running. |
Jobs |
View the number of commands currently running in the background. |
Kill |
Terminate the process. |
Killall |
Terminate a process by process name. |
Pkill |
Terminate a process by process name. |
Crontab |
Scheduled Task Command. |
Ps |
Displays the process snapshot. |
Pstree |
Process is displayed in a tree. |
Nice/renice |
Adjust the program running priority. |
Nohup |
Ignore the pending signal and run the specified command. |
Pgrep |
Find the matching process. |
Runlevel |
View the current running level of the system. |
Init |
Switch the running level. |
Service |
Starting, stopping, restarting, and disabling system services also display the current status of all system services. |