• tal@lemmy.today
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    10 hours 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
    $
    
    • ThunderLegend@sh.itjust.works
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      2 hours 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.

    • TechLich@lemmy.world
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      8 hours 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
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        2 hours 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…