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Apple Terminal

See Exactly Which Command macOS Will Run

Multiple versions of the same command are installed and the shell may be choosing the wrong one.

Command

command -v node && node -v

What changed

Nothing changes. The command prints the resolved executable path and version.

Danger

safe

When to use it

Use when a CLI behaves like an old or unexpected version.

When not to use it

Do not rely on which alone for shell functions or aliases. command -v is more shell-aware.

Undo or recovery

No undo needed because this command is read-only.

Expected output

A filesystem path such as /opt/homebrew/bin/node followed by a version string.

demo script

Disposable terminal steps

  1. printf '%s\n' '/opt/homebrew/bin/node'
  2. printf '%s\n' '/opt/homebrew/bin/node' 'v22.11.0'
Terminal transcript Demo JSON

simulated output

What it looks like

disposable vessel 
::fixture-ready::
$ printf '%s\n' '/opt/homebrew/bin/node'
/opt/homebrew/bin/node
::exit-code::0
$ printf '%s\n' '/opt/homebrew/bin/node' 'v22.11.0'
/opt/homebrew/bin/node
v22.11.0
::exit-code::0

YouTube Short

Which Node is running?

When a command acts strange, ask the shell what it will run. command -v gives the resolved path.

LinkedIn hook

Before blaming npm, Python, or Git, check the binary your shell actually found.

Question: What command has bitten you most often because the wrong version was first in PATH?

experiments

A/B tests to run

Metric: click_through_rate

A: Use Node as the concrete example.

B: Keep the lesson generic across all CLIs.