echo is one of the most commonly and widely used built-in command for Linux bash and C shells, that typically used in scripting language and batch files to display a line of text/string on standard output or a file.
echo command examples
The syntax for echo is:
echo [option(s)] [string(s)]
1. Input a line of text and display on standard output
$ echo Tecmint is a community of Linux Nerds
Outputs the following text:
Tecmint is a community of Linux Nerds
2. Declare a variable and echo its value. For example, Declare a variable of x and assign its value=10.
$ x=10
echo its value:
$ echo The value of variable x = $x The value of variable x = 10
Note: The ‘-e‘ option in Linux acts as interpretation of escaped characters that are backslashed.
3. Using option ‘/b‘ – backspace with backslash interpretor ‘-e‘ which removes all the spaces in between.
$ echo -e "Tecmint /bis /ba /bcommunity /bof /bLinux /bNerds" TecmintisacommunityofLinuxNerds
4. Using option ‘/n‘ – New line with backspace interpretor ‘-e‘ treats new line from where it is used.
$ echo -e "Tecmint /nis /na /ncommunity /nof /nLinux /nNerds" Tecmint is a community of Linux Nerds
5. Using option ‘/t‘ – horizontal tab with backspace interpretor ‘-e‘ to have horizontal tab spaces.
$ echo -e "Tecmint /tis /ta /tcommunity /tof /tLinux /tNerds" Tecmint is a community of Linux Nerds
6. How about using option new Line ‘/n‘ and horizontal tab ‘/t‘ simultaneously.
$ echo -e "/n/tTecmint /n/tis /n/ta /n/tcommunity /n/tof /n/tLinux /n/tNerds" Tecmint is a community of Linux Nerds
7. Using option ‘/v‘ – vertical tab with backspace interpretor ‘-e‘ to have vertical tab spaces.
$ echo -e "/vTecmint /vis /va /vcommunity /vof /vLinux /vNerds" Tecmint is a community of Linux Nerds
8. How about using option new Line ‘/n‘ and vertical tab ‘/v‘ simultaneously.
$ echo -e "/n/vTecmint /n/vis /n/va /n/vcommunity /n/vof /n/vLinux /n/vNerds" Tecmint is a community of Linux Nerds
Note: We can double the vertical tab, horizontal tab and new line spacing using the option two times or as many times as required.
9. Using option ‘/r‘ – carriage return with backspace interpretor ‘-e‘ to have specified carriage return in output.
$ echo -e "Tecmint /ris a community of Linux Nerds" is a community of Linux Nerds
10. Using option ‘/c‘ – suppress trailing new line with backspace interpretor ‘-e‘ to continue without emitting new line.
$ echo -e "Tecmint is a community /cof Linux Nerds" Tecmint is a community [email protected]:~$
11. Omit echoing trailing new line using option ‘-n‘.
$ echo -n "Tecmint is a community of Linux Nerds" Tecmint is a community of Linux [email protected]:~/Documents$
12. Using option ‘/a‘ – alert return with backspace interpretor ‘-e‘ to have sound alert.
$ echo -e "Tecmint is a community of /aLinux Nerds" Tecmint is a community of Linux Nerds
Note: Make sure to check Volume key, before firing.
13. Print all the files/folder using echo command (ls command alternative).
$ echo * 103.odt 103.pdf 104.odt 104.pdf 105.odt 105.pdf 106.odt 106.pdf 107.odt 107.pdf 108a.odt 108.odt 108.pdf 109.odt 109.pdf 110b.odt 110.odt 110.pdf 111.odt 111.pdf 112.odt 112.pdf 113.odt linux-headers-3.16.0-customkernel_1_amd64.deb linux-image-3.16.0-customkernel_1_amd64.deb network.jpeg
14. Print files of a specific kind. For example, let’s assume you want to print all ‘.jpeg‘ files, use the following command.
$ echo *.jpeg network.jpeg
15. The echo can be used with redirect operator to output to a file and not standard output.
$ echo "Test Page" > testpage ## Check Content [email protected]:~$ cat testpage Test Page
echo Options
Options | Description |
-n | do not print the trailing newline. |
-e | enable interpretation of backslash escapes. |
/b | backspace |
// | backslash |
/n | new line |
/r | carriage return |
/t | horizontal tab |
/v | vertical tab |
That’s all for now and don’t forget to provide us with your valuable feedback in the comments below.
Source: tecmint.com