find: Stop Guessing Where You Put That File

You know you have a file called config.json somewhere. You don't remember where. You could click through folders for ten minutes, or:

find . -name "config.json"

There it is. ./src/settings/config.json. That's find.

The Basic Pattern

find [where to look] [what to match]

The . means "current directory and everything under it." Use / for the entire system, ~ for your home folder, or any path you want.

Finding by Name

Exact match:

find . -name "README.md"

Wildcard:

find . -name ".txt"

All text files, anywhere in the tree.

Case-insensitive:

find . -iname "readme.md"

Matches README.md, Readme.md, readme.MD, etc.

Finding by Type

Only files (not directories):

find . -type f -name ".log"

Only directories:

find . -type d -name "test"

Finding by Time

Modified in the last 7 days:

find . -mtime -7

Modified more than 30 days ago:

find . -mtime +30

Minus means "less than", plus means "more than."

Finding by Size

Larger than 100MB:

find . -size +100M

Smaller than 1KB:

find . -size -1k

Suffixes: c (bytes), k (kilobytes), M (megabytes), G (gigabytes).

Limiting Depth

Don't want to search forever?

find . -maxdepth 2 -name ".js"

Only goes 2 levels deep.

Real Examples

Find all node_modules folders:

find . -type d -name "node_modules"

Find large files hogging space:

find . -type f -size +50M

Find old log files:

find /var/log -name ".log" -mtime +90

find vs grep

Different tools, different jobs:

find searches for files by name, size, date

grep searches for text inside files

Chain them together:

find . -name ".log" | xargs grep "error"

Find all log files, then search inside them.

Quick Reference

| What you want | Command | |---------------|---------| | By name | find . -name "file.txt" | | Wildcard | find . -name ".js" | | Case-insensitive | find . -iname "readme" | | Only files | find . -type f | | Only directories | find . -type d | | Recent files | find . -mtime -7 | | Large files | find . -size +100M | | Limit depth | find . -maxdepth 2 |

Practice

find is essential in CTF challenges where flags hide in unexpected places. Master find and nothing stays hidden for long.

Yes, find has a hundred flags. You need five. The ones above cover 95% of real searching.*