Shell Scripting

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Allowed: Release Announcement of a command-line program designed for scripted use (e.g. bash, bats, awk, jq, coreutils/moreutils)
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In general, if your submission text is primarily shell code, then it is welcome here!

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What are the most inscrutable lines of $SHELL you've ever written? (programming.dev)

submitted 1 year ago* (last edited 1 year ago) by gamma to c/shell

31 comments fedilink hide all child comments

I'm sure some of you have absolute monstrosities of sigils (I know I do, in my .zshrc alone). Post them without context, and try and guess what other users's lines are. If you want to provide context or guess, use the markdown editor to spoiler-tag your guesses and explanations!

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[–] xcjs 3 points 1 year ago* (last edited 1 year ago) (1 children)

It's not bash itself that was the complex part exactly, but I have a CI/CD pipeline that generates epub files from markdown. In some cases I have custom designed covers, but where a cover doesn't exist I have a bash script generate one using Imagemagick.

I wanted to generate the cover in one command to lessen performance impacts and disk I/O, but it took me a few weeks to figure out how to do it all in a single Imagemagick command:

convert \
    -size 960x1536 \
    -background "${backgroundColor}" \
    -fill "${textColor}" \
    -font "Liberation-Serif" \
    -pointsize 96 \
    -gravity north \
    caption:"${title}" \
    -bordercolor "rgb(0, 0, 0)" \
    -border 2 \
    -bordercolor "${borderColor}" \
    -border 40 \
    -background none \
    -fill "${textColor}" \
    -font "Liberation-Serif" \
    -pointsize 48 \
    -gravity south \
    -geometry +0-800 \
    -annotate +0+40 "${author}" \
    "${destination}cover.jpg"

Eventually it made an abstract sense to me, and I was able to bring it down to two commands and then finally one. This generates a cover with a selected background color (based on content type) and contains title text that will wrap to an inner border.

I think I had to give up on the author being wrapped, but it's much smaller than the title anyway.

[–] gamma 2 points 1 year ago (1 children)

Nice work! I've definitely had some fun with convert recently, as you might tell from the community banner.

spoiler

It is an image showing the script I used to create it 😛.

[–] xcjs 1 points 1 year ago* (last edited 1 year ago) (1 children)

That's certainly a script! 😅

[–] gamma 2 points 1 year ago* (last edited 1 year ago) (1 children)

It's a little more complex than needed, for the pixelated background I used xcolor names and then modulated them darker, but then relented and used hexcodes for the text in the foreground.

[–] xcjs 1 points 1 year ago

It's very impressive! I try to write legible code first, and if my shell scripts get too complex, I move on to another tool typically:

C# scripting
Python
PowerShell
Node.js

That might be why I don't have many cryptic examples.