How to separate fields with space or tab in awk

Question

While playing with awk I came to execute:

ls -la >> a.txt ; awk {'print $5  $1'} a.txt ;

This is giving output like:

53277-rw-------
52347-rw-------

How can I get a space between these two friends of output?

As an advice, you should not parse the output of ls. This will bite you in the back sooner or later. — gniourf_gniourf, Dec 23 '12 at 10:08
In awk, to concatenate two strings, you just place them side-by-side -- print $5 $1 — glenn jackman, Dec 23 '12 at 12:31
Possible duplicate of How do I select a field/column from the output of `ls -l`? — kenorb, Apr 10 '16 at 04:28
@kenorb and close voters, the linked duplicate is not a duplicate at all. They know already how to print fields by premise (awk {'print $5 $1'} a.txt). They're asking how to put a space in between field #1 and field #5. — kos, Apr 11 '16 at 17:49

score 130 · Accepted Answer · edited Apr 13 '17 at 12:24

130

Just change the line to

ls -la >> a.txt ; awk {'print $5 "        " $1'} a.txt ;

this should print the output with spaces.

Hope this helps.

Edit:

As suggested by McNisse you can use printf, which would provide you good output format

ls -la >> a.txt ; awk {'printf ("%5s\t%s\n", $5, $1)'} a.txt ;

edited Apr 13 '17 at 12:24

Community

1

answered Dec 23 '12 at 09:35

devav2

36,312

8

The printf function provides better control, specially if you want to format numbers. printf("%s\t%s\n", $5, $1) – McNisse Dec 23 '12 at 10:11
1

Is there a typo in above answer? what does 5s mean in awk {'printf ("%5s\t%s\n", $5, $1)'} – Vishal Oct 15 '19 at 13:06
@Vishal - if you insert a number after the % sign, then you specify a field width, in this case 5. The output will be right aligned. If you enter a negative number, the output will be aligned on the left. – twan163 Nov 22 '19 at 15:55

score 101 · Answer 2 · answered Dec 23 '12 at 12:33

101

Another awk-specific technique, use the "output field separator"

ls -la | awk -v OFS='\t' '{print $5, $1}'

The comma is crucial here.

answered Dec 23 '12 at 12:33

glenn jackman

17,900

this works but cause $1 to go to newline – loretoparisi Oct 26 '16 at 21:47
@loretoparisi, no it doesn't. There are likely to be \r characters at your end-of line. – glenn jackman Sep 28 '21 at 13:15
+1, This is a clean way to do it. Please note that doesn't work with print $0 to print all fields with the OFS separator, so for such a need we can use column: ... | column -s ' ' -t – 4wk_ Apr 03 '23 at 09:36

score 26 · Answer 3 · answered Nov 22 '17 at 02:49

26

A simple way to get tabs is:

awk {'print $5"\t"$1'}

answered Nov 22 '17 at 02:49

a06e

13,223
26
70
104

1

Thanks I hate it. But slightly less than the other options. – daknowles Apr 25 '20 at 14:59

score 9 · Answer 4 · answered Sep 18 '14 at 22:55

9

I know this is an old thread, but I'm just learning and found these posts helpful. My best solution was to use gawk to insert spaces between the variables for you.

ls -la | gawk '{print $1, $9}'

answered Sep 18 '14 at 22:55

codeJediNinjaDork

115

4

-1: Nothing new. gawk, mawk, or any other awk, they all insert spaces if you use the comma, which is what this answer says. – muru Sep 18 '14 at 23:19
1

Should be ls -la | awk '{print $1, $9}'. As muru said gawk isn't necessary. – Nick Crawford Aug 25 '15 at 16:33

score 6 · Answer 5 · edited Apr 13 '17 at 12:37

To place the space between the arguments, just add " ", e.g. awk {'print $5" "$1'}.

However it is not recommended to parse output of ls command, since it's not reliable and output is for humans, not scripts. Therefore use alternative commands such as find or stat.

Here is example using GNU stat:

$ stat -t *
001.txt 23 8 81a4 501 20 1000004 242236402 1 0 0 1460260387 1460260239 1460260239 1460260194 4096
7c1c.txt 21 8 81a4 501 20 1000004 242236595 1 0 0 1460261322 1460260486 1460260486 1460260486 4096

which will print you machine-friendly output (in terse form), so you can get exactly what you need. Then use -c to use specific format, or use awk, cut or read to get the right columns.

Check stat --help for further options. For example to print day of modification, check this example.

It appears the OP is trying to parse the output for human reading purposes and not for the purposes of running a script (like for i in ls; do $i). — mchid, Nov 05 '19 at 18:15

How to separate fields with space or tab in awk

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