Linux file system and basic commands (Prince have regrets.)

Linux file system and basic commands

Instructions and examples:

1.PWD: This command displays the working directory

[Email protected] sysconfig]# pwd

/etc/sysconfig

2.echo: This command displays the command back

[Email protected] sysconfig]# echo $PATH

/usr/lib64/qt3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root

3.CD: This command is a toggle command

[[Email protected] sysconfig]# CD

[[email protected] ~]# This example to switch home directory

[Email protected] etc]# CD ~

[[email protected] ~]# This command is also switch home directory

[Email protected] home]# CD ~ming

[[email protected] ming]# This command is to switch to the home directory of the specified user

[Email protected]/]# CD-

/root

[Email protected] ~]# CD-

/

[Email protected]/]# CD-

/root

[[email protected] ~]# switch back and forth between the last directory and the current directory ;

4.ls:

[[email protected] ~]# ls-a Show all files, including. and. Hidden files are included .

. Anaconda-ks.cfg. bash_logout. bashrc. config. lesshst. TCSHRC

.. . bash_history. Bash_profile. Cache. cshrc. SSH

[[email protected] ~]# ls-a Show almost all the files

Anaconda-ks.cfg. bash_logout. bashrc. config. lesshst. TCSHRC

. bash_history. Bash_profile. Cache. cshrc. SSH

[[email protected] ~]# ls-l listing the details of the file

Total 4

-RW-------. 1 root root 2639 Mar 4 21:30 anaconda-ks.cfg

[Email protected] ~]# ls-l

Total 4

-RW-------. 1 root root 2639 Mar 4 21:30 anaconda-ks.cfg

[[email protected] ~]# LS-LH This command to convert values in units

Total 4.0K

-RW-------. 1 root root 2.6K Mar 4 21:30 anaconda-ks.cfg

[[email protected] ~]# ls-ld/etc View the properties of the directory itself

Drwxr-xr-x. 119 root root 8192 Mar 6 11:52/etc

Ls-r Recursive display

[[email protected]/]# ls

Bin Dev Home Lib media opt root sbin sys usr Wen

Boot etc Li lib64 mnt proc run SRV tmp var

[[email protected]/]# ls-r Descending display

Wen usr sys sbin Root opt media lib home dev bin

var tmp srv run proc mnt lib64 li etc boot

5.cat:

[[email protected]/]# cat/etc/fstab display file contents

#

#/etc/fstab

# Created by Anaconda on Fri Mar 4 13:14:59 2016

#

# Accessible filesystems, by reference, is maintained under '/dev/disk '

# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info

#

UUID=2ADD5CE4-FBC0-4E3E-A6CA-4D43B052AA93/XFS Defaults 0 0

Uuid=31fe4ea9-d043-424b-9d64-254e40193750/boot XFS Defaults 0 0

UUID=C9FC5E6B-639A-46DC-BECD-F8D0D6AA6341/USR XFS Defaults 0 0

UUID=740E31FB-2FC2-4162-9FE5-171751ECD52E swap swap defaults 0 0

[[email protected]/]# cat-n/etc/fstab numbering the displayed rows

1

2#

3#/etc/fstab

4# Created by Anaconda on Fri Mar 4 13:14:59 2016

5#

6# Accessible filesystems, by reference, is maintained under '/dev/disk '

7# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info

8#

9uuid=2add5ce4-fbc0-4e3e-a6ca-4d43b052aa93/xfs defaults 0 0

uuid=31fe4ea9-d043-424b-9d64-254e40193750/boot xfs defaults 0 0

uuid=c9fc5e6b-639a-46dc-becd-f8d0d6aa6341/usr xfs defaults 0 0

uuid=740e31fb-2fc2-4162-9fe5-171751ecd52e Swap swap defaults

[[email protected]/]# cat-e/etc/fstab Display line terminator ($)

$

#$

#/etc/fstab$

# Created by Anaconda on Fri Mar 4 13:14:59 2016$

#$

# Accessible filesystems, by reference, is maintained under '/dev/disk ' $

# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info$

#$

UUID=2ADD5CE4-FBC0-4E3E-A6CA-4D43B052AA93/XFS Defaults 0 0$

Uuid=31fe4ea9-d043-424b-9d64-254e40193750/boot XFS Defaults 0 0$

UUID=C9FC5E6B-639A-46DC-BECD-F8D0D6AA6341/USR XFS Defaults 0 0$

UUID=740E31FB-2FC2-4162-9FE5-171751ECD52E Swap swap defaults 0 0$

6.TAC: This command is a reverse version of cat

[Email protected]/]# Cat/etc/fstab

#

#/etc/fstab

# Created by Anaconda on Fri Mar 4 13:14:59 2016

#

# Accessible filesystems, by reference, is maintained under '/dev/disk '

# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info

#

UUID=2ADD5CE4-FBC0-4E3E-A6CA-4D43B052AA93/XFS Defaults 0 0

Uuid=31fe4ea9-d043-424b-9d64-254e40193750/boot XFS Defaults 0 0

UUID=C9FC5E6B-639A-46DC-BECD-F8D0D6AA6341/USR XFS Defaults 0 0

UUID=740E31FB-2FC2-4162-9FE5-171751ECD52E swap swap defaults 0 0

[Email protected]/]# Tac/etc/fstab

UUID=740E31FB-2FC2-4162-9FE5-171751ECD52E swap swap defaults 0 0

UUID=C9FC5E6B-639A-46DC-BECD-F8D0D6AA6341/USR XFS Defaults 0 0

Uuid=31fe4ea9-d043-424b-9d64-254e40193750/boot XFS Defaults 0 0

UUID=2ADD5CE4-FBC0-4E3E-A6CA-4D43B052AA93/XFS Defaults 0 0

#

# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info

# Accessible filesystems, by reference, is maintained under '/dev/disk '

#

# Created by Anaconda on Fri Mar 4 13:14:59 2016

#/etc/fstab

#

7.file:

[[email protected]/]# file/etc/fstab This command is to view the type of file.

/etc/fstab:ascii text

8.date: This command displays the command for the system time

[[Email protected]/]# Date

Sun Mar 6 14:31:16 CST 2016

9.hwclock: This command is hardware time

[Email protected]/]# Hwclock

Sun Mar 02:32:42 PM CST-0.649588 seconds

Hwclock-s refers to the hardware and system synchronization

Hwclock-w refers to the system and hardware synchronization

10.cal: View calendar Commands

[[email protected]/]# cal

March 2016

Su Mo Tu We Th Fr Sa

1 2 3) 4 5

6 7 8 9 10 11 12

13 14 15 16 17 18 19

20 21 22 23 24 25 26

27 28 29) 30 31

types of files on the 11.linux system:

-: Regular file, sometimes using F logo;

d: catalog files;

B:block;

C:character devices;

L:symbolic link files; Symbolic link file;

P:pipe, Named Pipes;

S:SOKCET, socket file;

12.alias: command to name aliases

[[email protected]/]# alias cle= "Clear"

[[email protected]/]# alias

Alias cle= ' Clear '

Alias cp= ' Cp-i '

Alias egrep= ' Egrep--color=auto '

Alias fgrep= ' Fgrep--color=auto '

Alias grep= ' grep--color=auto '

Alias l.= ' ls-d. *--color=auto '

Alias ll= ' Ls-l--color=auto '

Alias ls= ' ls--color=auto '

Alias mv= ' Mv-i '

Alias rm= ' Rm-i '

Alias Which= ' Alias | /usr/bin/which--tty-only--read-alias--show-dot--show-tilde '

[[email protected]/]# Unalias CLE alias cancellation command

[Email protected]/]# CLE

-bash:cle:command not found

13.

To view a list of command history:

~]# history

Command usage:

History-c: Emptying the command history;

history-d OFFSET: Deletes the specified entry;

-A appends the current buffered history row to the history file

-N reads all unread rows from the history file

-R reads the history file and appends the contents to the History list

Invoke commands in the command history list for re-execution purposes:

!#: Once again execute the # command in the history list;

!! : To execute the last command once more;

! STRING: Executes the most recent command in the command history list that begins with the specified string;

14.

Shutdown

Shutdown [OPTIONS ...] [TIME] [WALL ...]

Options:

-H: Shutdown

-R: Restart

-C: Cancel the shutdown or restart operation that has not been performed

Time:

(1) hh:mm

(2) +m

15.

Which:

which [OPTIONS] [PROGRAMS]

-A: Displays all matching program files, not the first;

[Email protected]/]# which-a/etc/host*

/usr/bin/which:no host.conf in (/etc)

/usr/bin/which:no hostname in (/etc)

/usr/bin/which:no hosts in (/etc)

/usr/bin/which:no Hosts.allow in (/etc)

/usr/bin/which:no Hosts.deny in (/etc

16.whereis:

Whereis [Options] name ...

-B Search only displays specific paths for binaries

[Email protected]/]# Whereis-b/etc

ETC:/usr/local/etc

-M Search only for manuals

[Email protected]/]# WHEREIS-M/etc

Etc:[[email protected]/]

17.who:

Who-show who's logged on

who [OPTION] ...

-R: Displays the operating level;

[Email protected]/]# Who-r

Run-level 3 2016-03-06 10:41

-B: The time the system starts;

[Email protected]/]# Who-b

System Boot 2016-03-06 18:40

W:

W-show who was logged on and what they was doing.

w [options] user [...]

[Email protected]/]# W

15:02:16 up 4:25, 2 users, load average:0.00, 0.01, 0.05

USER TTY from [email protected] IDLE jcpu PCPU

Root tty1 13:57 1:04m 0.21s 0.21s-bash

Root pts/0 192.168.1.110 13:58 0.00s 1.41s 0.01s

WHOAMI:

Etc:[[email protected]/]# WhoAmI

Root

Whoami-print effective UserID

This article is from the "Li Wenming blog" blog, make sure to keep this source http://liwenming18.blog.51cto.com/11068518/1748058

Linux file system and basic commands (Prince have regrets.)