Master the Linux ‘find’ Command: 7 Powerful Ways to Locate and Manage Files

The find command is a must‑know tool for Linux backend and system administrators, and it frequently appears in technical interviews.

If your Linux server has a directory named logs , how would you delete log files that haven’t been accessed for over a year?

First change to the target directory with cd, then run: find . -type f -atime +365 -exec rm -rf {} \; If you’re not familiar with the command, the article introduces seven real‑world uses of find:

1. Find files by name or regular expression

Search by exact name: find . -name test.txt Search for all PDF books using a pattern: find ./yang/books -name "*.pdf" Specify regular files explicitly:

find ./yang/books -type f -name "*.pdf"

2. Find files of different types

Search directories: find . -type d -name "yang*" Search symbolic links:

find . -type l -name "yang*"

3. Find files by timestamps

Linux tracks three timestamps: atime (last access), mtime (last content modification), and ctime (last metadata change). To find files whose atime is older than one year: find . -type f -atime +365 To find files modified exactly five days ago (without the “+” operator): find . -type f -mtime 5 To locate files whose ctime is between 5 and 10 days ago:

find . -type f -ctime +5 -ctime -10

4. Find files by size

The -size option accepts units: b (512‑byte blocks), c (bytes), w (two‑byte words), k (kilobytes), M (megabytes), G (gigabytes). “+” means greater than, “-” means less than. Example – find files between 10 MiB and 1 GiB:

find . -type f -size +10M -size -1G

5. Find files by permissions

Use -perm to match permission bits. Example – find all files with 777 permissions:

find . -type f -perm 777

6. Find files by ownership

Use -user to specify the owning user. Example – find files owned by user yang:

find -type f -user yang

7. Execute a command on found files

The -exec action lets you run a command for each matched file. Re‑using the interview question, you can delete the old log files with: find . -type f -atime +365 -exec rm -rf {} \; Here {} is a placeholder for the current file, and the command must end with an escaped semicolon \;. Demonstrating the placeholder effect, compare: find . -type f -atime +5 -exec ls {} \; versus find . -type f -atime +5 -exec ls \; Without the placeholder, the ls runs on all files, not just the matched ones.

After learning these seven uses, the original interview problem becomes straightforward to solve.