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linuxsortingcommand-lineterminalpipeline

Order command output using line field

I want to order some command output (using pipeline), taking into account some field from the output.

For example, if I run l command, I have:

-rw-r-----  1 matias matias  67843408 sep 11 08:55 file1
-rw-r-----  1 matias matias      1952 oct 23 12:05 file2
-rw-r-----  1 matias matias       965 oct 23 10:14 asd.txt
-rw-r-----  1 matias matias    892743 sep  3 08:36 aaa.txt
-rw-r-----  1 matias matias    892743 ago 18 08:09 qwe

I want to order this output according for example by the day of the month field, so the output should be:

-rw-r-----  1 matias matias    892743 sep  3 08:36 aaa.txt
-rw-r-----  1 matias matias  67843408 sep 11 08:55 file1
-rw-r-----  1 matias matias    892743 ago 18 08:09 qwe
-rw-r-----  1 matias matias      1952 oct 23 12:05 file2
-rw-r-----  1 matias matias       965 oct 23 10:14 asd.txt

How can I do this? I usually use grep, cat, l, ls, ll, but I can't figure out how to achieve this.

Solution

  • You can use sort with the 7th column:

    $ sort -k7 -n file
-rw-r-----  1 matias matias    892743 sep  3 08:36 aaa.txt
-rw-r-----  1 matias matias  67843408 sep 11 08:55 file1
-rw-r-----  1 matias matias    892743 ago 18 08:09 qwe
-rw-r-----  1 matias matias      1952 oct 23 12:05 file2
-rw-r-----  1 matias matias       965 oct 23 10:14 asd.txt

    From man sort:

      -n, --numeric-sort
          compare according to string numerical value

   -k, --key=KEYDEF
          sort via a key; KEYDEF gives location and type

    However, this is quite fragile and, in general, you should not parse the output of ls.