Linux Learning: Chapter Three-linux common commands -1__linux

Prompt:

[Root@localhost ~]#

[Login user name @ Host name current directory] Prompt

~ Home Directory/root/home/aa

Prompt: # Super User $ normal user

Format of a Linux command 1, command [options] [parameters]

LS list shows the contents of the directory

① command name: ls

Command English original intention: List

Path to command:/bin/ls

Execute Permissions: All Users

Feature Description: Displaying catalog files

②ls Name Direct return, display the contents of the directory

Ls-l Long Format display (abbreviated option with a minus sign, full option with two minus)

-RW-------1 root root 1190 08-10 23:37 anaconda-ks.cfg

First item: Permissions

Second item: 1 reference count

Third item: Root owner

Item Fourth: Root Group

Item Fifth: Size byte

Sixth last modification time

Seventh Item file name

Ls-a Display all files (including hidden files)

Ls-al

Ls-h file size shown as common size units B KB MB

Ls-l file name

The ls-d directory name shows the long format of the directory itself, not the contents of the directory

Two directory operation command 1) CD switching directory

① Command name: CD

Command English original meaning: Change directory (changing directories)

Command path: Shell built-in command

Execute permissions: All users ②CD/USR/LOCAL/SRC

Relative path: Find by referencing the current directory.    Be sure to determine the current directory first. Root] #cd. /usr/local/src

Absolute path: Cd/usr/local/src from the root directory, first-level recursive lookup. In any directory, access to the specified location

CD ~ Enter current user's home directory/root/home/aa/

Cd

CD-Go to last directory

Cd.. Go to the previous level directory

Cd. Enter current directory

2) PWD Displays the current directory

Command name: pwd

Command English original intent: Print working directory

Path to command:/BIN/PWD

Execute Permissions: All Users

3 Linux Common Directory

/root directory

/bin command to save a directory (commands that ordinary users can read)

/boot boot directory, start related files

/dev Device File save directory

/ETC configuration File Save Directory

/home Common User's home directory

/lib function System Library Save directory

/MNT System Mount Directory

/media Mount Directory

/root Super User's home directory

/tmp Temp directory

/sbin command to save a directory (a directory that superuser can use)

/proc writes directly to memory

/sys

/USR System software Resource Directory

/usr/bin/system command (normal user)

/usr/sbin/system commands (super User)

/var System Related Document content

/var/log/System Log Location

/var/spool/mail/system default Mailbox location

Server Operation specification:

1 in the specified directory, carry out the specified operation 2 The remote server does not allow shutdown, can only restart 3 to create a directory

mkdir Directory Name

Command name: mkdir

Command English original meaning: make directories

Path to command:/bin/mkdir

Execute Permissions: All Users

Mkdir-p 11/22/33/44 Recursive Directory creation

4) Delete Directory

RmDir directory can only delete empty directories

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