How to print "-n" without issuing a newline?

Question

I'm trying to print -n using the echo command. But if i simply type echo -n, it only issues a newline, not show up -n, instead it issues a newline.

Does echo -n -- -n work (don't have any linux box handy to test)? — n0rd, Nov 23 '15 at 19:07
I'm installing Ubuntu in a virtual machine and it seems to be very slow, wait. — Star OS, Nov 23 '15 at 19:07
I've checked - it does not. Probably because it's internal bash command and it's not using getopt (???) to parse command line — n0rd, Nov 23 '15 at 19:46
This question is asked and answered in http://pubs.opengroup.org/onlinepubs/9699919799/utilities/echo.html - - "Conforming applications that ... could possibly be expecting to echo a -n, should use the printf utility derived from the Ninth Edition system" — Brandin, Nov 25 '15 at 09:42
... 100 reputation on all of my communities? Nice reward, moderators! — Star OS, Dec 15 '15 at 08:58

score 31 · Accepted Answer · edited Apr 13 '17 at 12:37

31

The problem is that echo interprets the -n as an argument. On the default bash implementation, that means (from help echo):

  -n  do not append a newline

There are various ways of getting around that:

Make it into something that isn't an option by including another character. For example, tell echo not to print a newline with -n, then tell it to interpret backslash escapes with -e and add the newline explicitly.
```
$ echo -ne '-n\n'
-n
```
Alternatively, just include a space
```
$ echo " -n"
 -n
```
That, however, adds a space which you probably don't want.
Use a non-printing character before it. Here. I am using the backspace (\b)
```
$ echo -e "\b-n"
-n
```
This also adds an extra character you probably don't want.
Use trickery
```
$ echo n- | rev
-n
```
The rev command simply prints its output reversed.
Use the right tool for the job
```
$ printf -- '-n\n'
-n
```

edited Apr 13 '17 at 12:37

Community

1

answered Nov 23 '15 at 18:06

terdon

104,404

You are correct that any \\ valid character will do. – Pilot6 Nov 23 '15 at 18:08
@Pilot6 yeah but the problem with that approach (yours and mine) is that it adds an extra character. That can cause issues down the line. Especially if you then want to parse it and try something like grep '^-n'. pritnf is the way to go, really. – terdon Nov 23 '15 at 18:10
Well, printf is better anyway, but the question is regarding just echo. – Pilot6 Nov 23 '15 at 18:11
3

It looks like echo -e "-n\c" does the exact thing. – Pilot6 Nov 23 '15 at 18:29
@Pilot6 nice! What is \c? I don't see it in man ascii. Also, I just realized that echo -ne '-n\n' prints -n\n and only that, just as desired. – terdon Nov 23 '15 at 18:39
1

\c is suppress further output – Pilot6 Nov 23 '15 at 18:45
@Pilot6 ah, it's an echo-specific thing. Good to know, thanks! – terdon Nov 23 '15 at 18:52
\b is backspace, \a is a bell. – 123 Nov 24 '15 at 14:08

A.B. · Answer 2 · 2015-11-23T18:49:03.763

16

Sometimes it's a good idea to use the right tool. You could use printf instead:

% printf "-n\n"       
-n

edited Nov 23 '15 at 18:49

answered Nov 23 '15 at 17:50

A.B.

92,275

1

This is a good idea, since there are many variants of echo, while printf is better standardized. – 200_success Nov 25 '15 at 00:22
This is a preferred idea for portability – Sergiy Kolodyazhnyy Dec 08 '15 at 21:15

Pilot6 · Answer 3 · 2015-11-23T18:46:34.547

7

You can use this command, but it adds an extra space.

echo -e  "\r-n"

This is a kind of a hack.

-e enables backslash command symbols.

\r is a carriage return.

Actually any \ valid character will do in any place of the string.

You can see which are valid by help echo.

echo "-n" does not work because -n is used as a parameter for echo.

P.S. The best solution IMHO is

echo -e "-n\c"

It does not add any extra characters.

echo -e "-n\n"

prints the same but with a new line char.

edited Nov 23 '15 at 18:46

answered Nov 23 '15 at 17:56

Pilot6

92,169

1

Wov! This is better than mine; can you explain a bit for "beginners" ;-) – Sadi Nov 23 '15 at 17:59
Thanks, I've also noticed that it doesn't matter where you add the carriage return, at the beginning or the end. – Sadi Nov 23 '15 at 18:05
@Sadi yes, that's because adding anything makes it a non-valid option. -n is valid, -nfoo is not so that will be printed. – terdon Nov 23 '15 at 18:20
@terdon man echo has it too. But help is a bit better. – Pilot6 Nov 23 '15 at 18:22
I know it has it, it's just not relevant. /bin/echo is a completely different thing and when you run echo in bash, you get the builtin which can be quite different depending on your shell. – terdon Nov 23 '15 at 18:23
You can also print the extra character, and then erase it: echo -e "- \x08n" – Benubird Nov 24 '15 at 10:57

score 5 · Answer 4 · edited Nov 23 '15 at 18:19

5

I think if you definitely want to use echo only, this should satisfy you:

echo "-n "

This works because while -n is a valid option for echo, -n with a space after it is not. Since it isn't an option, echo just prints it.

edited Nov 23 '15 at 18:19

terdon

104,404

answered Nov 23 '15 at 17:53

Sadi

11,084

Most viewers here may only want "-n", not "-n ". – Star OS Dec 08 '15 at 14:17

score 5 · Answer 5 · answered Nov 23 '15 at 21:53

5

You guys are really overthinking it.

 echo -e \\055n

Or with no trailing newline

 echo -en \\055n

answered Nov 23 '15 at 21:53

Joshua

719

How is printf "-n\n" an overthinking? – Dmitry Grigoryev Nov 24 '15 at 12:01
Yup, I just answered this way. Will delete my answer. This is relatively portable in that it works with built-in echo and /bin/echo at least if invoked as echo -e "\055n" – abligh Nov 24 '15 at 14:05
-en is not what i want. – Star OS Dec 05 '15 at 19:24

jiwopene · Answer 6 · 2015-12-08T20:43:36.043

2

In Bash script you can run:

echo -n -
echo n

Or in interacive shell:

echo -n - ; echo n

This echoes a - character and an n character.

edited Dec 08 '15 at 20:43

answered Nov 23 '15 at 20:30

jiwopene

219

Did you try it? It is wrong. – Pilot6 Nov 23 '15 at 20:34
@Pilot6 Did you try it? It is not wrong. – user12205 Nov 23 '15 at 21:11
First command outputs -pilot6@Pilot6:~$. The second outputs n. – Pilot6 Nov 23 '15 at 21:13
@Pilot6 Depends on whether you're running it in interactive terminal or in a bash script, which isn't specified in the question. OTOH if you need it in the terminal it is simple to just combine the two lines with && - I wouldn't really say this answer is wrong. – user12205 Nov 23 '15 at 21:16
I'll edit it so it becomes much clearer it's for a bash script. – Star OS Dec 08 '15 at 14:14
This uses trickery. You can print anything with it. For example, this prints "cats": echo -n c ; echo -n a ; echo -n t ; echo s If it was echo 2 ; echo 3, it would output 2 in line 1 and 3 in line 2. By doing -n to all of these except the last it would bring all the characters to line 2. So -(line1)n(line2) becomes (line1)-n(line2) – Star OS Dec 08 '15 at 21:32
Just some explanation about how it works ^^^ – Star OS Dec 08 '15 at 21:52

score 2 · Answer 7 · answered Nov 24 '15 at 12:17

2

To extend @A.B's answer, the only portable way to use echo is to refrain from using any options like -n. Consider use printf instead where available. This reference page provides more details and explains very well when and how echo and printf should be used:

Nowadays, echo(1) is only portable if you omit flags and escape sequences. Use printf(1) instead, if you need more than plain text.

answered Nov 24 '15 at 12:17

Dmitry Grigoryev

1,960
14
23

I've you're gonna extend an answer, please edit the answer. – Star OS Dec 08 '15 at 14:13
I'm not sure it's a good idea to alter someone else's answer to the point when it will have more text from me than from the original author. – Dmitry Grigoryev Dec 08 '15 at 14:46

score 1 · Answer 8 · answered Nov 25 '15 at 20:01

1

Three other ways:

$ echo -e '\x2dn' # ASCII hexadecimal value
-n
$ echo -e '\u002dn' # Unicode code point
-n
$ echo -e '\u2dn' # Unicode code point shortened
-n

answered Nov 25 '15 at 20:01

kos

41,378

jiwopene · Answer 9 · 2015-12-08T21:23:16.423

0

You can run

printf -n;echo

Tested in Busybox Ash

edited Dec 08 '15 at 21:23

answered Dec 08 '15 at 20:46

jiwopene

219

1

Ash? Ash? POKEMON i mean, what? – Star OS Dec 08 '15 at 21:07
I ran 'busybox ash' – jiwopene Dec 08 '15 at 21:19
Say "Busybox" or "Busybox Ash". Not just "Ash" beacuse people may think of that pokemon character or the ******* ash from volcanoes. – Star OS Dec 08 '15 at 21:22
Better. alt255alt255 – Star OS Dec 08 '15 at 21:25
@StarOS ash is the name of the Almquist Shell. – muru Dec 08 '15 at 21:51

How to print "-n" without issuing a newline?

9 Answers9