'echo' newline suppression

Question

Why doesn't $echo '-n' write -n on terminal although -n is written within single quotes?

I guessed that this is a shell syntax question (ie, bash or whatever). — Pointy, Apr 15 '10 at 12:35
@tripleee - I'm not sure this question is a dup of the cited question. The question in the body seems to be different than the titular digest. Could you take a second look at it? — jww, Apr 25 '18 at 23:13
Isn't the duplicate for the ***opposite*** situation (unintentional vs. intentional)? — Peter Mortensen, Nov 05 '21 at 15:05

score 13 · Accepted Answer · answered Apr 15 '10 at 12:36

13

Because the quotes are processed by the shell and the echo command receives plain -n. If you want to echo -n, you can e.g. printf '%s\n' -n

answered Apr 15 '10 at 12:36

laalto

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it's a shame `--` (end of options) isn't supported :( – extraneon Apr 15 '10 at 12:37
Following works with bash: echo -e -n\\c – Tino Dec 01 '10 at 00:57

score 4 · Answer 2 · answered Jan 23 '13 at 10:14

4

I found that the following just works in bash:

echo -n PRINT_THIS

So, you should put -n the first place.

answered Jan 23 '13 at 10:14

Erik Bitemo

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https://ss64.com/bash/echo.html – JJFord3 Jan 08 '19 at 15:59

score 2 · Answer 3 · edited Nov 05 '21 at 16:48

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You should try to use the more portable printf as far as possible.

edited Nov 05 '21 at 16:48

Peter Mortensen

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answered Apr 15 '10 at 14:05

ghostdog74

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Can you provide an example in your answer? (But ***without*** "Edit:", "Update:", or similar - the answer should appear as if it was written today.) – Peter Mortensen Nov 05 '21 at 16:49

score 2 · Answer 4 · answered Apr 15 '10 at 14:13

2

You could try

echo -e '\055n'

answered Apr 15 '10 at 14:13

kennytm

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Pointy · Answer 5 · 2010-04-15T12:39:53.537

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The quotes don't help because ... ugh, it's hard to explain. The shell strips the quotes off before the "echo" command itself is evaluated, so by that time they don't matter.

Try this:

echo - -n

That's not documented as working (I'm running Ubuntu Linux), but echo is almost certainly a built-in to whatever shell you're using, so the man page is questionable anyway. It does work for me. (I'm running zsh because I'm really suave and sophisticated).

edit: well it seems that the bash builtin edit doesn't behave that way. I don't know what to suggest; this:

echo '' -n

will give you "-n" preceded by a space, which (depending on what you're doing) might be OK.

edited Apr 15 '10 at 12:39

answered Apr 15 '10 at 12:34

Pointy

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Doesn't work for me. Output `- -n` – extraneon Apr 15 '10 at 12:35
For me that does this > echo - -n - -n – Greg Reynolds Apr 15 '10 at 12:35
Hmm, well as I just noted in an edit, it probably varies from shell to shell. – Pointy Apr 15 '10 at 12:37
Sorry I didn't get you. Can you explain your point please? – Happy Mittal Apr 15 '10 at 12:38
1

Linux/UNIX systems support multiple command line interpreters (shells). The `echo` command is usually built in to each of those, and the exact syntax and features can vary. You're probably using the default shell, `bash`, which doesn't work like my shell (`zsh`) does. – Pointy Apr 15 '10 at 12:41
https://ss64.com/bash/echo.html – JJFord3 Jan 08 '19 at 16:00

score 0 · Answer 6 · edited Nov 05 '21 at 14:56

0

Not quite there:

echo -e 'a-n\b\b\b '
 -n

Surprisingly, this works:

echo -e '-n\b'
-n

And here is a solution I can explain:

echo "foobar" | sed 's/.*/-n/'
-n

edited Nov 05 '21 at 14:56

Peter Mortensen

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answered Apr 16 '10 at 04:21

user unknown

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Re *"here is a solution I can explain"*: Can you reveal the explanation? – Peter Mortensen Nov 05 '21 at 14:56
The sed command takes the "foobar" and replaces it with "-n". – user unknown Nov 05 '21 at 15:57

'echo' newline suppression

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