Linux basic commands

Command:

(1) File system related

Directory Management

File Management

File View

File editing

(2) System Management related

Directory-related commands:

Current directory or working directory

Home directory: Home

Root:/root

Normal User:/home/username

~: User's home directory

Cd:

CD or CD ~: Back to the current user's home directory

CD ~username: Switch to the home directory of the specified user

CD-: Switch back and forth between the previous directory and the current directory

.: Root Directory

.. : Top level Directory

Related environment variables:

PWD: The current directory path is saved

OLDPWD: Last directory path

PWD: Show current directory

Ls:list

Displays a list of files under the specified path

ls [OPTION] ... [DIR] ...

-A,--all: Displays all files, including hidden files

-L: Long format

-rw-r--r--1 root root 44800 14:32 Install.log

-rw-r--r--:

Leftmost first bit: file type

-, D, L, B, C, p, s

9 bits in the back: access rights, Perm

Number: Number of times a file has been hard linked

Left Root: Owner of File

Right root: Group of files

44800: Size of File

14 14:32: Last modified time for a file

Install.log: File name

-H,--human-readable: unit conversion

-D: Displays the relevant properties of the directory itself, typically with-l

-R,--reverse: Reverse Display

-R,--recursive: recursive

mkdir [Options]/path/to/somewhere

-P: exists in no error, and can automatically create the required directories

-V: Show more information

-M MODE: Specify permissions directly when creating a directory

Tree

-D: Show only directories

-L Level: Specifies the number of levels to display

-P Pattern: Displays only the paths that are matched by the specified pattern

RmDir: Delete Empty directory

rmdir [OPTION] ... DIRECTORY ...

-V: Display process;

File Management:

Copy command: CP

CP [OPTION] ... [-T] SOURCE DEST

CP [OPTION] ... SOURCE ... DIRECTORY

CP [OPTION] ...-t DIRECTORY SOURCE ...

CP SRC DEST

SRC is a file:

If the target does not exist: Create a new dest and populate the SRC content into dest

If the directory exists:

If Dest is a file: overwrites the content in SRC to dest

We recommend that you use the-i option for the CP command

If Dest is a directory: Create a new file with the same name as the original file under Dest and populate the contents of SRC with the new file

CP SRC ... DEST

Src... : Multiple Files

Dest must exist and be directory, other situations will be error

CP SRC DEST

SRC is the directory:

Use option at this time:-R

If Dest does not exist: creates the specified directory and copies all files in the SRC directory to dest

If dest exists:

If Dest is a file: Error

If Dest is a directory: Copy all files in src directory to dest

Common options:

-I: Interactive

-R,-r: recursively replicate directories and all internal content

-A: Archive, equivalent to-DR--preserv=all

-d:--no-dereference--preserv=links

--preserv[=attr_list]

mode, ownership, timestamp, links, xattr, context, all

-P:--preserv=mode,ownership,timestamp

-V:--verbose

-F:--force

Mv:move, moving files

MV [OPTION] ... [-T] SOURCE DEST

MV [OPTION] ... SOURCE ... DIRECTORY

MV [OPTION] ...-t DIRECTORY SOURCE ...

Common options:

-I: Interactive

-F: Mandatory

Rm:remove, deleting

RM [OPTION] ... FILE ...

Common options:

-I: Interactive

-F: Force delete

-R: Recursive

Text File View Class command:

Cat, TAC

More

More [OPTIONS ...] FILE ...

-D: Show page flipping and exit tips

Less

Less [OPTIONS ...] FILE ...

Head

Head [OPTION] ... [FILE] ...

-C #: Specify get before # bytes

-N #: Specifies the first # line to get

Tail

tail [OPTION] ... [FILE] ...

-C #: Specifies the # bytes after fetching

-N #: Specifies the # line after fetch

-F: Trace displays new additions to the file

Time Stamp management tool for files:

File: metadata, data

View file Status: Stat

Three time stamps:

Access time: Atime, reading the contents of a file

Modify Time: Modified, Mtime, change file contents (data)

Change time: Changing times, ctime, meta data changes

Touch command:

Touch [OPTION] ... FILE ...

-a:only Atime

-m:only Mtime

-T STAMP:

[[Cc]yy] MMDDHHMM[.SS]

-C: If the file does not exist, it is not created

Text Processing tools: WC, cut, sort, uniq

WC command:

WC [OPTION] ... [FILE] ...

-l:lines

-w:words

-c:characters

Cut command:

Cut [OPTION] ... [FILE] ...

-D DELIMITER: Indicates delimiter

-F Fileds:

#: Section # Fields

#,#[,#]: Discrete multiple fields, such as 1,3,6

#-#: Multiple consecutive fields, such as 1-6

Mixed use: 1-3,7

--output-delimiter=string

Sort command:

Sort [OPTION] ... [FILE] ...

-F: Ignore character case

-R: Reverse order

-T DELIMITER: Field delimiter

-K #: Sort the specified fields as standard

-N: Sorting by numeric size

-u:uniq, sort after go heavy

Uniq command:

Uniq [OPTION] ... [FILE] ...

-C: Shows the number of occurrences per line

-D: Show only rows that have been repeated

-U: Show only rows that have not been duplicated

Note: Repeat for continuous and identical sides

System Management Related commands:

Shutdown:

Halt, Poweroff, shutdown, init 0

Restart:

Reboot, shutdown, init 6

Associated with User login:

Who, WhoAmI, W

Shutdown or restart:

Halt, Poweroff: Turn off the machine

Reboot: Restart

-F: Force, do not call shutdown

-P: Power off

Shutdown

shutdown [OPTION] ... Time [MESSAGE]

-r:reboot

-h:halt

-c:cancel

Time:

Now: Immediately

+m: Relative time notation, how long after the start of the command submission; for example, +3

HH:MM: Absolute time indication, specify time

User login Information View command:

WHOAMI: Displays the currently logged in active user

Who: All current logon sessions for the system

W: All current logon sessions and actions made by the system

This article is from the "Ricky Technology Blog" blog, make sure to keep this source http://r1cky.blog.51cto.com/10646564/1773852

Linux basic commands