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alloyed • today at 3:34 PM • 2 replies • view on HN

the point is well-taken, but i do want to show the bash version just for fun:

    podman image ls --all | sed 's/\s\s\+/\t/g' | tee >(head -n 1) >(tail -n +2 | sort -hrk 5) >/dev/null
this is _still_ all text, and we're relying heavily on sort to do a bunch of internal parsing and be in agreement with podman about how sizes should be formatted. also, for "real world" work, i dunno if the tee trick here has any kind of order guarantees, just that it works fine in this case. I'd probably just end up dropping the header and living with worse output in reality

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jcgl • today at 3:49 PM

Ooh, I was so hoping someone would take up the challenge! This is a far shorter answer than I had honestly thought was possible. More readable too, somehow? Great use of tee that I would never have come up with (though I hear what you say about there maybe not being ordering guarantees).

Unfortunately, it's not 100% correct, due to misaligned headers:

  REPOSITORY TAG IMAGE ID CREATED SIZE
  registry.fedoraproject.org/fedora-toolbox 44 5a36f433c691 2 months ago 2.14 GB
  quay.io/keycloak/keycloak latest 1361d6e49205 9 days ago 478 MB
  ...
I think that speaks to your final point, which is spot-on:

> I'd probably just end up dropping the header and living with worse output in reality

This pretty much sums up plain text and unix shell imo. It's very much the pragmatic solution here, and it's what ~100% of shell scripters would choose to do. And it should make anyone question the orthodoxy around the "power" of plain text in shells.

i15e • today at 6:06 PM

A variant:

  docker image ls -a | stdbuf -oL sed -r 's/\s{2,}/\t/g' | { head -n1; tail -n+2 | sort -hrk5 -t$'\t'; } | column -ts$'\t'
I used docker since that's what I have installed and I assume the output is equivalent.

sort's -t is set to tab for field separation.

stdbuf sets sed's output to only buffer a line at a time and flush, so the head in the {...} command group doesn't completely consume stdin's contents before it's passed to tail.

The column command recreates the space-aligned table based on tab-delimited input.

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