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Echo newline in Bash prints literal \n

How do I print a newline? This merely prints \n :

$ echo -e "Hello,\nWorld!"
Hello,\nWorld!

You could use printf instead:

printf "hello\nworld\n"

printf has more consistent behavior than echo . The behavior of echo varies greatly between different versions.

Make sure you are in Bash. All these four ways work for me:

echo -e "Hello\nworld"
echo -e 'Hello\nworld'
echo Hello$'\n'world
echo Hello ; echo world
echo $'hello\nworld'

prints

hello
world

$'' strings use ANSI C Quoting :

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.

You could always do echo "" .

For example,

echo "Hello,"
echo ""
echo "World!"

Try

echo -e "hello\nworld"
hello
world

It worked for me in the nano editor.

From the man page:

-e enable interpretation of backslash escapes

In the off chance that someone finds themselves beating their head against the wall trying to figure out why a coworker's script won't print newlines, look out for this:

#!/bin/bash
function GET_RECORDS()
{
   echo -e "starting\n the process";
}

echo $(GET_RECORDS);

As in the above, the actual running of the method may itself be wrapped in an echo which supersedes any echos that may be in the method itself. Obviously I watered this down for brevity. It was not so easy to spot!

You can then inform your comrades that a better way to execute functions would be like so:

#!/bin/bash
function GET_RECORDS()
{
   echo -e "starting\n the process";
}

GET_RECORDS;

Simply type

echo

to get a new line

这在Raspbian 中对我有用

echo -e "hello\\nworld"

POSIX 7 on echo

http://pubs.opengroup.org/onlinepubs/9699919799/utilities/echo.html

-e is not defined and backslashes are implementation defined:

If the first operand is -n, or if any of the operands contain a <backslash> character, the results are implementation-defined.

unless you have an optional XSI extension.

So I recommend that you should use printf instead, which is well specified:

format operand shall be used as the format string described in XBD File Format Notation [...]

the File Format Notation :

\\n <newline> Move the printing position to the start of the next line.

Also keep in mind that Ubuntu 15.10 and most distros implement echo both as:

  • a Bash built-in: help echo
  • a standalone executable: which echo

which can lead to some confusion.

str='hello\nworld'
$ echo | sed "i$str"
hello
world

For only the question asked (not special characters etc) changing only double quotes to single quotes.

echo -e 'Hello,\nWorld!'

Results in:

Hello,
World!

You can also do:

echo "hello
world"

This works both inside a script and from the command line.

On the command line, press Shift + Enter to do the line break inside the string.

This works for me on my macOS and my Ubuntu 18.04 (Bionic Beaver) system.

它在 CentOS 中对我有用:

echo -e ""hello\nworld""

I just use echo without any arguments:

echo "Hello"
echo
echo "World"

My script:

echo "WARNINGS: $warningsFound WARNINGS FOUND:\n$warningStrings

Output:

WARNING : 2 WARNINGS FOUND:\nWarning, found the following local orphaned signature file:

On my Bash script I was getting mad as you until I've just tried:

echo "WARNING : $warningsFound WARNINGS FOUND:
$warningStrings"

Just hit Enter where you want to insert that jump. The output now is:

WARNING : 2 WARNINGS FOUND:
Warning, found the following local orphaned signature file:

There is a new parameter expansion added in Bash 4.4 that interprets escape sequences:

${parameter@operator} - E operator

The expansion is a string that is the value of parameter with backslash escape sequences expanded as with the $'…' quoting mechanism.

$ foo='hello\nworld'
$ echo "${foo@E}"
hello
world

One more entry here for those that didn't make it work with any of these solutions, and need to get a return value from their function:

function foo()
{
    local v="Dimi";
    local s="";
    .....
    s+="Some message here $v $1\n"
    .....
    echo $s
}

r=$(foo "my message");
echo -e $r;

Only this trick worked on a Linux system I was working on with this Bash version:

GNU bash, version 2.2.25(1)-release (x86_64-redhat-linux-gnu)

This could better be done as

x="\n"
echo -ne $x

-e option will interpret backslahes for the escape sequence
-n option will remove the trailing newline in the output

PS: the command echo has an effect of always including a trailing newline in the output so -n is required to turn that thing off (and make it less confusing)

If you're writing scripts and will be echoing newlines as part of other messages several times, a nice cross-platform solution is to put a literal newline in a variable like so:

newline='
'

echo "first line$newlinesecond line"
echo "Error: example error message n${newline}${usage}" >&2 #requires usage to be defined

You could also use echo with braces,

$ (echo hello; echo world)
hello
world

This may not apply in your case, but it's something that has confused me in the past:

Wrong

Writing "hello\\nworld" in Bash gives you a string with a new-line character in it, and echo -e prints that exact string.

Right

Writing $'hello\\nworld' or

"hello
world"

gives you a string with a new-line character in it, and plain echo prints that exact string. Which is good, since as you've seen, echo -e isn't always supported.

Sometimes you can pass multiple strings separated by a space and it will be interpreted as \\n .

For example when using a shell script for multi-line notifcations:

#!/bin/bash
notify-send 'notification success' 'another line' 'time now '`date +"%s"`

在bash配置文件(MacOx,iTerm)中用作别名时,我必须用双引号将文本引起来。

alias helloworld="echo -e \"hello \n world\""

This got me there....

outstuff=RESOURCE_GROUP=[$RESOURCE_GROUP]\\nAKS_CLUSTER_NAME=[$AKS_CLUSTER_NAME]\\nREGION_NAME=[$REGION_NAME]\\nVERSION=[$VERSION]\\nSUBNET-ID=[$SUBNET_ID]
printf $outstuff

Yields:

RESOURCE_GROUP=[akswork-rg]
AKS_CLUSTER_NAME=[aksworkshop-804]
REGION_NAME=[eastus]
VERSION=[1.16.7]
SUBNET-ID=[/subscriptions/{subidhere}/resourceGroups/makeakswork-rg/providers/Microsoft.Network/virtualNetworks/aks-vnet/subnets/aks-subnet]

Backslash \\<\/code> is a special character in bash. To print characters like '".,<\/code> we need to put \\<\/code> in front of them.

echo \\n

With jq :

$ jq -nr '"Hello,\nWorld"'
Hello,
World

Additional solution:

In cases, you have to echo a multiline of the long contents (such as code/ configurations)

For example:

  • A Bash script to generate codes/ configurations

echo -e , printf might have some limitation

You can use some special char as a placeholder as a line break (such as ~ ) and replace it after the file was created using tr :

echo ${content} | tr '~' '\n' > $targetFile

It needs to invoke another program ( tr ) which should be fine, IMO.

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