How do I echo a string with multiple spaces in bash "untouched"?

Question

I assigned a var like this:

MYCUSTOMTAB='     '

But using it in echo both:

echo $MYCUSTOMTAB"blah blah"

or

echo -e $MYCUSTOMTAB"blah blah"

just returns a single space and the rest of the string:

 blah blah

How can I print the full string untouched? I want to use it for have a custom indent because \t is too much wide for my tastes.

Put the variable *inside* double quotes. This is one of the main reasons we constantly harp "quote your variables". [Security implications of forgetting to quote a variable in bash/POSIX shells](https://unix.stackexchange.com/questions/171346/security-implications-of-forgetting-to-quote-a-variable-in-bash-posix-shells) — glenn jackman, Apr 01 '16 at 14:44

score 51 · Accepted Answer · answered Apr 01 '16 at 14:46

51

Put your variable inside double quote to prevent field splitting, which ate your spaces:

$ MYCUSTOMTAB='     '
$ echo "${MYCUSTOMTAB}blah blah"
     blah blah

answered Apr 01 '16 at 14:46

cuonglm

150,973
38
327
406

score 12 · Answer 2 · edited May 05 '17 at 13:26

12

As suggested in this answer quoting the variable is enough.

The reason why quoting is needed in your case is because without it bash applies the split+glob operator onto the expansion of $MYCUSTOMTAB. The default value of $IFS contains the TAB character, so in echo -e $MYCUSTOMTAB"blah blah", $MYCUSTOMTAB is just split into nothing so it becomes the same as if you had written:

echo -e "blah blah"

(you probably don't want -e here btw).

You can also use printf instead of echo:

printf '%s\n' "$MYCUSTOMTAB"

printf '%s\n' "${MYCUSTOMTAB}blah blah"

Or if you want printf to do the same kind of \n, \t expansions that echo -e does, use %b instead of %s:

printf '%b\n' "${MYCUSTOMTAB}blah blah"

For reference read Why is printf better than echo?

edited May 05 '17 at 13:26

Stéphane Chazelas

522,931
91
1,010
1,501

answered Apr 01 '16 at 14:45

techraf

5,831
10
33
51

2

While strictly true, the cause here is totally unrelated to the difference between `printf` and `echo`. While `printf` is certainly more portable and has some upsides, its major downside is that it is ugly and unreadable, and way more difficult to understand. – Wouter Verhelst Apr 01 '16 at 14:50
2

printf is "better" if you use it properly: you need to write `printf "blah%sblah\n" "$MYCUSTOMTAB"` -- if the variable contains any %s, %d, etc, you'll get the wrong output otherwise. – glenn jackman Apr 01 '16 at 14:51

score 2 · Answer 3 · answered Apr 01 '16 at 14:47

2

I think you just have to use double quotes for your variable

echo -e "$MYCUSTOMTAB"."blah blah"

answered Apr 01 '16 at 14:47

mnille

529
5
16

This doesn't work for me. In output I get the dot - it's not a concatenation operator in this case. However the following is working: `echo "$MYCUSTOMTAB""blah blah"` – Jaro Apr 09 '19 at 10:04

score 1 · Answer 4 · answered Apr 01 '16 at 14:50

1

I know your question is tagged bash but anyway, for maximum portability and reliability, I would use:

printf "%sblah blah\n" "$MYCUSTOMTAB"

or

someString="blah blah"
printf "%s%s\n" "$MYCUSTOMTAB" "$someString"

answered Apr 01 '16 at 14:50

jlliagre

60,319
10
115
157

How do I echo a string with multiple spaces in bash "untouched"?

4 Answers4

Linked