Linux essence set

Linux essence set

 

Linux Command list
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Command description
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Clear terminal screen
The reset uses the default terminal to set the reset terminal.
Finger displays information on system users
Who displays the current Login User
Whoami is your login name
ID: displays the ID of your account and group, that is, UID and GID.
Date: displays the current date and time.
Cal displays the calendar of the current month
Exit to exit the Current Shell
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Common BASH Shell Meta-tables
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Metacharacter description
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$ Shell variable
~ The specified home directory variable.
& Background Command Execution Method
; Command Terminator
<> Input/output redirection
| Command Pipeline
*? [] Shell wildcard
'"/Metacharacters reference
'COMMAND replacement
() {} Command Group
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Best Practice: Avoid using metacharacters whenever possible when you type a command, unless you need to use the special features of metacharacters.

On the terminal, type:
Man whoami
Display:
 
Note that whoami (1) is displayed on the top, and (1) indicates that whoami is a command.

Number table on the manual page
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Description
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1. commands that can be executed by all users
2 Linux system call
3. Database subroutine
4. Special Device Files
5 File Format
6 Games
7 macro packages
8. commands that only root users can execute
9 Linux connotation subroutine
N unclassified new commands
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Easy-to-Forget shutdown command
Shutdown instance table
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Command description
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Shutdown-H + 4 minutes to stop the system
Shutdown-R + 4 restart the system within 4 minutes
Shutdown-H now stop the system immediately
Shutdown-R now restart the system immediately
Shutdown-C cancel the scheduled stop
Halt stop the system immediately
Reboot immediately restarts the system
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