Linux file and directory management command base

Keywords: Linux CentOS Anaconda

1. Command basis

1.1 command operation syntax

  • Command [parameter] [file]

    • Parameter, optional

    • Documents, optional

2. Basic command

2.1. View the current working directory

  • pwd

    • print name of current/workin directory

    • Print name or working directory

      [root@oldboyedu ~]# pwd
/root
[root@oldboyedu ~]# cd /opt/
[root@oldboyedu /opt]# pwd
/opt
[root@oldboyedu /opt]# cd /etc/
[root@oldboyedu /etc]# pwd
/etc
[root@oldboyedu /etc]#

2.2. Change directory

  • cd

    • cd directory

      [root@oldboyedu /etc]# cd - return to last directory
/opt
[root@oldboyedu /opt]# cd.. go to the next level directory
[root@oldboyedu /]# cd. Go to the current directory
[root@oldboyedu /]# 
[root@oldboyedu /]# cd ~ to the current user's directory

Relative path and absolute path:

  • Relative path:
    • Paths that do not start from / are relative paths
  • Absolute path
    • Path from / to

2.3. Display in tree structure

  • tree

    • -L number of layers

      [root@oldboyedu ~]# tree -L 1 /
/
├── bin -> usr/bin
├── boot
├── dev
├── etc
├── home
├── lib -> usr/lib
├── lib64 -> usr/lib64
├── media
├── mnt
├── opt
├── proc
├── root
├── run
├── sbin -> usr/sbin
├── srv
├── sys
├── tmp
├── usr
└── var

    • -d display directory

      [root@oldboyedu ~]# tree -L 1 -d /etc/
/etc/
├── abrt
├── alternatives
├── audisp
├── audit
├── bash_completion.d
├── binfmt.d
├── chkconfig.d
├── cron.d

2.4 create directory

  • mkdir

    [root@oldboyedu ~]# ls
anaconda-ks.cfg
[root@oldboyedu ~]# mkdir oldboy
[root@oldboyedu ~]# ls
anaconda-ks.cfg  oldboy
[root@oldboyedu ~]# ls /
bin   dev  home  lib64  mnt  proc  run   srv  tmp  var
boot  etc  lib   media  opt  root  sbin  sys  usr
[root@oldboyedu ~]# mkdir /oldboy
[root@oldboyedu ~]# ls
anaconda-ks.cfg  oldboy
[root@oldboyedu ~]# ls /
bin   dev  home  lib64  mnt     opt   root  sbin  sys  usr
boot  etc  lib   media  oldboy  proc  run   srv   tmp  var

    • -p recursive creation

      [root@oldboyedu ~]# mkdir sun/yu
mkdir: cannot create directory 'sun/yu': No such file or directory
#mkdir: cannot create directory 'sun/yu': no such file or directory
[root@oldboyedu ~]# mkdir -p sun/yu
[root@oldboyedu ~]# ls
anaconda-ks.cfg  oldboy  sun
[root@oldboyedu ~]# ls sun/
yu

2.5 creating documents

  • touch

    [root@oldboyedu ~]# touch 1
[root@oldboyedu ~]# ls
1  anaconda-ks.cfg  oldboy  sun
    • {} generate sequence
    #What do I do if I want to create 100 txt files?
[root@oldboyedu ~]# touch {1..100}.txt
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root 0 Apr  5 09:04 100.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 10.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 11.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 12.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 13.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 14.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 15.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 16.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 17.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 18.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 19.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 1.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 20.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 21.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 22.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 23.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 24.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 25.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 26.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 27.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 28.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 29.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 2.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 30.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 31.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 32.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 33.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 34.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 35.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 36.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 37.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 38.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 39.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 3.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 40.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 41.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 42.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 43.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 44.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 45.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 46.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 47.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 48.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 49.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 4.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 50.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 51.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 52.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 53.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 54.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 55.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 56.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 57.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 58.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 59.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 5.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 60.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 61.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 62.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 63.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 64.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 65.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 66.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 67.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 68.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 69.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 6.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 70.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 71.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 72.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 73.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 74.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 75.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 76.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 77.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 78.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 79.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 7.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 80.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 81.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 82.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 83.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 84.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 85.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 86.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 87.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 88.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 89.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 8.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 90.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 91.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 92.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 93.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 94.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 95.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 96.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 97.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 98.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 99.txt
-rw-r--r--. 1 root root 0 Apr  5 09:04 9.txt

    #If I create four directories of a b c d in the current directory, and then create four files of a b c d, will it succeed
[root@oldboyedu ~]# mkdir a b c d
[root@oldboyedu ~]# ls
a  b  c  d
[root@oldboyedu ~]# touch a b c d
[root@oldboyedu ~]# ll
total 0
drwxr-xr-x. 2 root root 6 Apr  5 09:06 a
drwxr-xr-x. 2 root root 6 Apr  5 09:06 b
drwxr-xr-x. 2 root root 6 Apr  5 09:06 c
drwxr-xr-x. 2 root root 6 Apr  5 09:06 d
//Why is that? Because in Linux, everything is a file, and the directory is a file

2.5 display contents under the directory

  • ls (list)

    [root@oldboyedu ~]# ls
a  b  c  d

    • -l (long) the contents of the current directory are displayed in a long format

      [root@oldboyedu ~]# ls -l
total 0
drwxr-xr-x. 2 root root 6 Apr  5 09:06 a
drwxr-xr-x. 2 root root 6 Apr  5 09:06 b
drwxr-xr-x. 2 root root 6 Apr  5 09:06 c
drwxr-xr-x. 2 root root 6 Apr  5 09:06 d

    • -d only display its own directory

      [root@oldboyedu ~]# touch {1..5}.txt
[root@oldboyedu ~]# ls
1.txt  2.txt  3.txt  4.txt  5.txt  a  b  c  d
[root@oldboyedu ~]# ls -d
.

    • -A shows all files, including hidden files (files starting with a)

      [root@oldboyedu ~]# ls -la
total 24
dr-xr-x---.  6 root root 213 Apr  5 09:10 .
dr-xr-xr-x. 17 root root 224 Apr  5 09:03 ..
-rw-r--r--.  1 root root   0 Apr  5 09:10 1.txt
-rw-r--r--.  1 root root   0 Apr  5 09:10 2.txt
-rw-r--r--.  1 root root   0 Apr  5 09:10 3.txt
-rw-r--r--.  1 root root   0 Apr  5 09:10 4.txt
-rw-r--r--.  1 root root   0 Apr  5 09:10 5.txt
drwxr-xr-x.  2 root root   6 Apr  5 09:06 a
drwxr-xr-x.  2 root root   6 Apr  5 09:06 b
-rw-------.  1 root root 554 Apr  4 18:35 .bash_history
-rw-r--r--.  1 root root  18 Dec 29  2013 .bash_logout
-rw-r--r--.  1 root root 176 Dec 29  2013 .bash_profile
-rw-r--r--.  1 root root 176 Dec 29  2013 .bashrc
drwxr-xr-x.  2 root root   6 Apr  5 09:06 c
-rw-r--r--.  1 root root 100 Dec 29  2013 .cshrc
drwxr-xr-x.  2 root root   6 Apr  5 09:06 d
-rw-r--r--.  1 root root 129 Dec 29  2013 .tcshrc

    • -A shows all files, excluding files beginning with

      [root@oldboyedu ~]# ls -lA
total 24
-rw-r--r--. 1 root root   0 Apr  5 09:10 1.txt
-rw-r--r--. 1 root root   0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root   0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root   0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root   0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root   6 Apr  5 09:06 a
drwxr-xr-x. 2 root root   6 Apr  5 09:06 b
-rw-------. 1 root root 554 Apr  4 18:35 .bash_history
-rw-r--r--. 1 root root  18 Dec 29  2013 .bash_logout
-rw-r--r--. 1 root root 176 Dec 29  2013 .bash_profile
-rw-r--r--. 1 root root 176 Dec 29  2013 .bashrc
drwxr-xr-x. 2 root root   6 Apr  5 09:06 c
-rw-r--r--. 1 root root 100 Dec 29  2013 .cshrc
drwxr-xr-x. 2 root root   6 Apr  5 09:06 d
-rw-r--r--. 1 root root 129 Dec 29  2013 .tcshrc

2.6 copying files and directories

  • cp (copy)

    • cp [OPTION]... SOURCE... DIRECTORY
      Options source directory

      • -r recursion, copying directories

        [root@oldboyedu ~]# ls
1.txt  2.txt  3.txt  4.txt  5.txt  a  b  c  d
[root@oldboyedu ~]# cp a /opt/
cp: omitting directory 'a
cp:omitting directory'a
[root@oldboyedu ~]# cp -r a /opt/
[root@oldboyedu ~]# ll /opt/
total 0
drwxr-xr-x. 2 root root 6 Apr  5 09:14 a

      • -p keep file properties

        [root@oldboyedu ~]# cp -p 2.txt /opt/
[root@oldboyedu ~]# ll 2.txt /opt/2.txt 
-rw-r--r--. 1 root root 0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root 0 Apr  5 09:10 /opt/2.txt

      • -a keep file properties and links

        [root@oldboyedu ~]# ll /etc/system-release
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 /etc/system-release -> centos-release
[root@oldboyedu ~]# cp -a /etc/system-release ./
[root@oldboyedu ~]# ll /etc/system-release system-release 
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 /etc/system-release -> centos-release
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release

      • -i confirm

        [root@oldboyedu ~]# ls
1.txt  2.txt  3.txt  4.txt  5.txt  a  b  c  d  system-release
[root@oldboyedu ~]# cp 1.txt /opt/
[root@oldboyedu ~]# cp 1.txt /opt/
cp: overwrite '/opt/1.txt'? y
//It's because of alias CP ='cp-i '

2.7 view or set alias

  • alias

    [root@oldboyedu ~]# alias
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'

    • Setting aliases

      alias cp='cp -i'

How not to use aliases:

  1. [root@oldboyedu ~]# \cp 1.txt /opt/
  2. [root@oldboyedu ~]# /bin/cp 1.txt /opt/

2.8 deleting files or directories

  • rm

    • -f. force deletion (only files can be deleted)

      [root@oldboyedu ~]# rm -f 1.txt 
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 a
drwxr-xr-x. 2 root root  6 Apr  5 09:06 b
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release
[root@oldboyedu ~]# rm -f a
rm: cannot remove 'a': Is a directory
rm:Cannot delete“ a": Is a directory

    • -r recursively delete, delete directories and files

      [root@oldboyedu ~]# rm -rf a
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 b
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release

    • -i confirm

      alias rm='rm -i'

Be careful:

  • Try not to use rm, if you want to use find instead
  • Set rm alias, for example: alias rm='echo, please use find '
  • Backup before delete
  • Move the file to be deleted to / tmp before deleting
  • Go to the directory where you want to delete the file and delete the file

2.9. Cancel alias

  • unalias

    [root@oldboyedu ~]# alias 
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'
[root@oldboyedu ~]# unalias cp
[root@oldboyedu ~]# alias 
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'

    [root@oldboyedu ~]# unalias cp
[root@oldboyedu ~]# 
[root@oldboyedu ~]# cp 2.txt /opt/
[root@oldboyedu ~]# cp 2.txt /opt/
[root@oldboyedu ~]# cp 2.txt /opt/

2.10 moving files or directories (equivalent to cutting)

  • mv

    [root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 b
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release
[root@oldboyedu ~]# mv a /opt/
mv: cannot stat 'a': No such file or directory
[root@oldboyedu ~]# mv -r a /opt/
mv: invalid option -- 'r'
Try 'mv --help' for more information.
[root@oldboyedu ~]# 
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 b
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release
[root@oldboyedu ~]# mv b /opt/
[root@oldboyedu ~]# ll /opt/
total 0
-rw-r--r--. 1 root root 0 Apr  5 09:25 1.txt
-rw-r--r--. 1 root root 0 Apr  5 09:30 2.txt
drwxr-xr-x. 2 root root 6 Apr  5 09:14 a
drwxr-xr-x. 2 root root 6 Apr  5 09:06 b
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 2.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release
[root@oldboyedu ~]# mv 2.txt /opt/
mv: overwrite '/opt/2.txt'? y
#mv: overwrite "opt/2.txt"?
#The reason is alias MV ='mv-i '
[root@oldboyedu ~]# ll /opt/
total 0
-rw-r--r--. 1 root root 0 Apr  5 09:25 1.txt
-rw-r--r--. 1 root root 0 Apr  5 09:10 2.txt
drwxr-xr-x. 2 root root 6 Apr  5 09:14 a
drwxr-xr-x. 2 root root 6 Apr  5 09:06 b
[root@oldboyedu ~]# ll
total 0
-rw-r--r--. 1 root root  0 Apr  5 09:10 3.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 4.txt
-rw-r--r--. 1 root root  0 Apr  5 09:10 5.txt
drwxr-xr-x. 2 root root  6 Apr  5 09:06 c
drwxr-xr-x. 2 root root  6 Apr  5 09:06 d
lrwxrwxrwx. 1 root root 14 Apr  4 18:05 system-release -> centos-release

    • -i confirm

      alias mv='mv -i'

2.11 output and printing

  • echo

    [root@oldboyedu ~]# echo "sun"
sun

    • -n do not wrap output

      [root@oldboyedu ~]# echo -n "sunsun"
sunsun[root@oldboyedu ~]#

    • -e support escape character

      • \n wrap

        [root@oldboyedu ~]# echo -e "sun\nsun"
sun
sun

      • \t tab

        [root@oldboyedu ~]# echo -e "sun\tsun"
sun	sun

2.12 output

  • printf

    [root@oldboyedu ~]# printf sun
sun[root@oldboyedu ~]# printf sunsss
sunsss[root@oldboyedu ~]#

Posted by wama_tech on Sun, 05 Apr 2020 03:28:23 -0700

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