Linux new line bash

How can I have a newline in a string in sh?

What should I do to have a newline in a string? Note: This question is not about echo. I’m aware of echo -e , but I’m looking for a solution that allows passing a string (which includes a newline) as an argument to other commands that do not have a similar option to interpret \n ‘s as newlines.

13 Answers 13

If you’re using Bash, you can use backslash-escapes inside of a specially-quoted $’string’ . For example, adding \n :

STR=$'Hello\nWorld' echo "$STR" # quotes are required here! 

If you’re using pretty much any other shell, just insert the newline as-is in the string:

Bash recognizes a number of other backslash escape sequences in the $» string. Here is an excerpt from the Bash manual page:

Words of the form $'string' are treated specially. The word expands to string, with backslash-escaped characters replaced as specified by the ANSI C standard. Backslash escape sequences, if present, are decoded as follows: \a alert (bell) \b backspace \e \E an escape character \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \\ backslash \' single quote \" double quote \nnn the eight-bit character whose value is the octal value nnn (one to three digits) \xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits) \cx a control-x character The expanded result is single-quoted, as if the dollar sign had not been present. A double-quoted string preceded by a dollar sign ($"string") will cause the string to be translated according to the current locale. If the current locale is C or POSIX, the dollar sign is ignored. If the string is translated and replaced, the replacement is double-quoted. 

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How to echo a New Line in Bash Shell Scripts

Learn various ways of displaying a new line in the output of echo command in Linux.

The echo command automatically adds a new line at the end. That’s cool.

But what if you want to display just an empty new line? Or if you want to output something that contains a new line?

The good news is that, echo lets you use the newline character \n to print a new line within the same output line if you use the -e option:

echo -e "Name\nAddress\nPhone Number"

If you run the above command, you’ll get this output:

Name Address Phone Number

That’s nice, right? Let’s have a more detailed look into it.

Display new line with -e flag of echo command (recommended)

A newline is a term we use to specify that the current line has ended and the text will continue from the line below the current one. In most UNIX-like systems, \n is used to specify a newline. It is referred to as newline character.

The echo command, by default, disables the interpretation of backslash escapes. So if you try to display a newline using the ‘\n’ escape sequence, you will notice a problem.

$ echo Hello\nworld Hellonworld $ echo 'Hello\nworld' Hello\nworld

Enclosing text in single quotes as a string literal does not work either.

That was not an expected output. To actually print a new-line, you can use the ‘-e’ flag to tell the echo command that you want to enable the interpretation of backslash escapes.

$ echo -e 'Hello\nworld' Hello world

Nice, that’s what you are looking for.

Let me some other ways to display the newline character.

echo a variable containing new line

You can store a string in a bash variable and then echo it using the ‘-e’ flag.

$ str="Hello\nworld" $ echo -e $str Hello world

Use the ‘$’ character instead of -e flag

The dollar symbol, ‘$’ is called the «expansion» character in bash. This is the character that I used in the earlier example to refer to a variable’s value in shell.

If you look closely at the snippet below, you will realize that the expansion character, in this case, acts to hold a temporary value.

$ echo Hello$'\n'world Hello world

Or, you can use the whole string as a ‘temporary variable’:

$ echo $'Hello\nworld' Hello world

I would prefer to use the -e flag, though.

echo your echo to print something with new line

When you echo a piece of text, the echo command will automatically add a newline (and here is how you can prevent it) to the end of your text.

This means that you can chain multiple echo commands together to cause a newline.

$ echo Hello; echo world Hello world

Use printf to print newline in Bash shell

printf is another command line tool that essentially prints text to the terminal, but it also allows you to format your text.

The usage is very simple and similar to echo but a bit more reliable and consistent.

$ printf 'Hello\nworld\n' Hello world

As expected, you have a newline without using any flags.

Conclusion

Personally, I would prefer sticking with the -e flag or go for the printf command for displaying the new lines in output. I recommend you to do the same but feel free to experiment.

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How to add new lines when using echo

I didn’t know about printf, with printf it works 😛 . so what does it make not working with echo then?

There are many different implementations of echo command incompatible with each other. Thus it is recommended to use more standard tool as printf . See unix.stackexchange.com/questions/65803/… for extended overview of the problem.

9 Answers 9

Pass the -e flag to echo to make it parse escaped characters such as «\r\n», like so:

echo -e "Line 1\r\nLine2" >> readme.txt 

A nice simple «-e» option to get escape sequences working — it says on another answer that echo is unreliable and doesn’t follow standards unlike printf .

echo

An echo implementation which strictly conforms to the Single Unix Specification will add newlines if you do:

But that is not a reliable behavior. In fact, there really isn’t any standard behavior which you can expect of echo .

OPERANDS

string

A string to be written to standard output. If the first operand is -n , or if any of the operands contain a character, the results are implementation-defined.

On XSI-conformant systems, if the first operand is -n , it shall be treated as a string, not an option. The following character sequences shall be recognized on XSI-conformant systems within any of the arguments:

\a — Write an .

\b — Write a .

\c — Suppress the that otherwise follows the final argument in the output. All characters following the \c in the arguments shall be ignored.

\f — Write a .

\n — Write a .

\r — Write a .

\t — Write a .

\v — Write a .

\\ — Write a character.

\0num — Write an 8-bit value that is the zero, one, two, or three-digit octal number num .

shopt -s xpg_echo echo hey\\nthere 

echo() case $ in (\ *) printf %b\\n "$*";; (*) IFS=\ $IFS printf %b\\n "$*" IFS=$ esac