Linux basic command-echo prints content to standard output

Echo

The echo instruction can output the content to standard output, dividing the string with white space, followed by a newline.

The scope of application of this command: RedHat, RHEL, Ubuntu, CentOS, Fedora.

1. Grammar

Echo [- neE] [arg...]

2. List of options

Option

Description

-n

The output string does not wrap

-e

Dealing with some special characters

\ a buzzer alarm

\ b Delete the previous character

\ C finally, there is no line change.

\ e output esc characters

\ f Wrap, the cursor stops in the same place

\ nWrap

\ r move the cursor to the first line without wrapping

\ t horizontal tab

\ v Vertical tab

\\ output\

The ASCII character represented by\ 0nnn octal nnn

\ xHH the ASCII character represented by the hexadecimal number HH

-E

Disable escape interpretation

3. Examples

1) use "\ f" line feeds

[root@localhost ~] # echo-e "hello\ fworld" / / the-e option must be used, and the cursor is still at the end after\ f wrapping

Hello

World

[root@localhost ~] #

2) use "\ n" line feeds

[root@localhost ~] # echo-e "hello\ nworld" / / the-e option must be used,\ nAfter a line break, the cursor is at the beginning

Hello

World

[root@localhost ~] #

3) output ascii characters

[root@localhost ~] # echo-e "\ x31" / / 31 in hexadecimal, converted to 49, the ascii character represented is 1

one

[root@localhost ~] #