find — Searching the Filesystem

The Swiss Army knife of file search

find walks a directory tree applying tests and actions to every entry. Once you internalize the syntax, you can answer almost any "where is the file that..." question.

The shape

find <path> <tests> <action>. Path defaults to . if omitted (BSD requires it explicitly; macOS works either way in practice). Tests filter; the default action is -print.

The tests you'll use most

• -name 'pattern' — glob match the basename. Quote it!
• -iname 'pattern' — case-insensitive.
• -type f — regular files. Also: d dir, l symlink.
• -size +10M — bigger than 10 MB. -1k, +500c (chars).
• -mtime -7 — modified in the last 7 days. -mmin -60 for minutes.
• -empty — empty files or dirs.
• -maxdepth 2 — don't recurse deeper. Put it before other tests for performance.

Actions

• -print — default. Print path.
• -delete — delete the match. Test with -print first!
• -exec cmd {} \; — run cmd once per match.
• -exec cmd {} + — batch matches into one cmd invocation. Like xargs but built in.

Real one-liners

• Find every Python file under home: find ~ -name '*.py'
• Files bigger than 100 MB: find / -type f -size +100M 2>/dev/null
• Old logs to delete: find /var/log -name '*.log' -mtime +30 -delete
• Pass to grep: find . -name '*.go' -exec grep -l TODO {} +

For interactive search, the fd tool from the modern-tools track is faster and friendlier — but find is on every Unix box.