The use of cat and Echo in Linux

• To create an empty file:

  Touch Akeke.log

• Use Echo to create a new file and simply edit a file:

  #echo "I am Wuyike" >wuyike.txt

  Then use Cat view: #cat wuyike.txt

• The difference between > and >>:

> is to empty and add new content, i.e. redirect

>> is to append a new content after the file content, that is, append redirect

• Append content to a file with Cat: (Pros: Multiple lines of content can be added)

  [email protected] ~]# cat >>wuyike.txt<<eof

  > I am Beautiful

  > EOF

  View results:

  [email protected] ~]# cat Wuyike.txt

  I am Wuyike

  I am Beautiful

• Using cat to redirect files:(Pros: Multiple lines of content can be added)

  [[Email protected] ~] #cat >wuyike.txt<<eof

  > I am a Student

  > EOF

  View results:

  [email protected] ~]# cat Wuyike.txt

  I am a Student

• You can also add multiple lines of content to a file using echo:

  [Email protected] ~]# echo "Wuyike

  > Wuyikeke ">>wuyike.txt

  View results:

  [email protected] ~]# cat Wuyike.txt

  I am a Student

  Wuyike

  Wuyikeke

• Correct output redirection: Code 1, using > or >>.

  Error output redirection: Code 2, using 2> or 2>>. Make the error message in the file.

  [Email protected] ~]# Ech wuyike 2>test.txt

  [email protected] ~]# cat Test.txt

  -bash:ech:command not found

  Or:

  [Email protected] ~]# echo 111 1>wuyike.txt 2>wuyike1.txt
  

  [email protected] ~]# cat Wuyike.txt

  111

  [email protected] ~]# cat Wuyike1.txt

  [Email protected] ~]#

  [Email protected] ~]# Ech 111 1>wuyike.txt 2>wuyike1.txt

  [email protected] ~]# cat Wuyike.txt

  [email protected] ~]# cat Wuyike1.txt

  -bash:ech:command not found

• 
  

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The use of cat and Echo in Linux