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Daniil Kornilov
Daniil Kornilov

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Seven terminal techniques, with shell and safety notes

#abotwrotethis #terminal #productivity #beginners

Disclosure: This article was created or edited with AI assistance. Revised on 13 October 2026 to remove promotional links and unsupported outcome claims. It is educational guidance, not a verified personal case study or a measured result. Examples are illustrative; use only your own documented experience and measurements.

The sections below present options and illustrative examples. Adapt them to the requirements of your project or role; they do not establish a universal rule or promise a result.

1. !! — Repeat Last Command

Forgot sudo? Don't retype the whole thing:

apt install nginx
# Permission denied
sudo !!
# Runs: sudo apt install nginx
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Inspect the previous command before rerunning it with elevated privileges.

2. ctrl + r — Reverse Search History

Stop scrolling through your history with the up arrow. Press ctrl + r and start typing. In common Bash/Readline setups, it searches your command history; behavior depends on the shell and configuration.

# Finds: docker compose up -d --build
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Press ctrl+r again to cycle through matches.

3. xargs — Turn Output Into Arguments

Preview .log files inside a dedicated sample directory:

# Preview the selected files first; -print0 handles spaces and newlines.
find ./sample-logs -type f -name '*.log' -print0 | xargs -0 -I {} printf '%s\n' '{}'
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Avoid piping broad process-name matches into kill. Inspect exact process IDs and understand what they belong to before stopping a process.

4. watch — Run a Command Repeatedly

Monitor a directory for changes every 2 seconds:

watch -n 2 ls -la /tmp/builds/
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Watch your API respond in real-time:

watch -n 1 'curl -s localhost:3000/health | jq .'
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5. tee — Write to File AND Terminal

See output while also saving it:

npm run build 2>&1 | tee build.log
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No more choosing between watching and logging.

6. comm — Compare Two Sorted Files

Find lines unique to each file:

comm -23 <(sort file1.txt) <(sort file2.txt)
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  • -23: Lines only in file1
  • -13: Lines only in file2
  • -12: Lines in both

Perfect for comparing dependency lists, configs, or data sets.

7. column -t — Format Output as a Table

Turn messy output into readable tables:

cat data.csv | column -t -s ','
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Before:

name,age,city
john,25,NYC
jane,30,LA
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After:

name  age  city
john  25   NYC
jane  30   LA
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Bonus: Command Chaining

Know the difference:

Operator Meaning
&& Run next only if previous succeeded
`\ \
{% raw %}; Run next regardless 
make build && make test && make deploy
# Only deploys if build AND test pass

make build || echo 'Build failed!'
# Shows error message only on failure
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What's your favorite terminal trick? Share it below!

These examples assume an interactive Bash-like shell. watch, jq and column may need separate installation. column -s is for simple delimiter-separated text, not a complete CSV parser with quoted fields. Redirection and pipelines may have different failure semantics; inspect each command before adapting it.

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