• tal@lemmy.todayEnglish
    15·
    21 days ago

    To be fair, a lot of the programs don’t use a single character, have multiple spaces between fields, and cut doesn’t collapse whitespace characters, so you probably want something more like tr -s " "|cut -d" " -f3 if you want behavior like awk’s field-splitting.

    $ iostat |grep ^nvme0n1
nvme0n1          29.03       131.52       535.59       730.72    2760247   11240665   15336056
$ iostat |grep ^nvme0n1|awk '{print $3}'
131.38
$ iostat |grep ^nvme0n1|tr -s " "|cut -d" " -f3
131.14
$
    • TechLich@lemmy.world
      91·
      21 days ago

      I never understood why so many bash scripts pipe grep to awk when regex is one of its main strengths.

      Like… Why

      grep ^nvme0n1 | awk '{print $3}'

      over just

      awk '/^nvme0n1/ {print $3}'

      • FooBarrington@lemmy.world
        12·
        21 days ago

        Because by the time I use awk again, I’ve completely forgotten that it supports this stuff, and the discoverability is horrendous.

        Though I’d happily fix it if ShellCheck warned against this…

    • ThunderLegend@sh.itjust.worksEnglish
      2·
      21 days ago

      This is awesome! Looks like an LPI1 textbook. Never got the certification but I’ve seen a couple books about it and remember seeing examples like this one.