How to Use the Find Command in Linux

How to use the find command to make life easier for all System Administrators.

What is Find?

The use of Find is pervasive I will divide the tutorial into five parts sorting the searches by names, permissions, users, groups, and size.

• Part 1. Basic search by the name of the file /directory.
• Part 2. Search for files based on your Permissions.
• Part 3. Filter searches by users and groups.
• Part 4. Perform search based on Dates.
• Part 5. Search for files and directories based on their size.

I will use some real examples that can happen in your day to day to speed up the search of files and directories.

Basic search by the name of the file /directory

Find all the files called solvetic.txt in the directory that you are.

find . -name solvetic.txt

Find all the files called solvetic.txt in the /home directory

find /home -name solvetic.txt

Find all the files named solvetic.txt inside / home regardless of uppercase or lowercase.

find /home -iname solvetic.txt

Search all directories called solvetic throughout the system.

find / -type d -name solvetic

Search only the php files called solvetic in the current directory.

find . -type f -name solvetic.php

Search all the php files in the current directory

find . -type f -name "*.php"

Now let's go to part 2 that would be looking for permissions.

Search for files based on the Permissions

Search all files in the current directory that have 777 permissions

find . -type f -perm 0777 -print

Search all files on the system that do not have 644 permissions

find / -type f ! -perm 644

Search all the files that SGID of 644

find / -perm 2644

Search all files with Sticky that have permissions 551 throughout the system.

find / -perm 1551

Search for all files that have special user permissions ( SUID )

find / -perm /u=s

Search all files that have Special Groups permissions ( SGID )

find / -perm /g+s

Search all files that have Read Only permission

find / -perm /u=r

Search all files that have executable permissions.

find / -perm /a=x

Search all files with permissions 777 and change them with chmod to 644.

find / -type f -perm 0777 -print -exec chmod 644 {} \;

Search all directories with 775 permissions and change them with chmod to 644

find / -type d -perm 775 -print -exec chmod 644 {} \;

Search the files called solvetic.txt in the current directory and delete them with rm.

find . -type f -name "solvetic.txt" -exec rm -f {} \;

Delete all files within a directory of the same extension

find . -type f -name "*.txt" -exec rm -f {} \;

Search all the blank files within a specific directory.

find /etc/html/www/ -type f -empty

Search for empty directories in a specific path (sub-folders are included).

find /etc -type d -empty

Search all hidden files in a certain directory.

find /tmp -type f -name “.*”

Now we go with the search filter.

Filter searches by Users and Groups

Search all the files and directories called solvetic belonging to the root user.

find / -user root -name solvetic

Search all the files belonging to the user so-and-so in all Home directories of the system.

find /home -user fulanito

Search all the files in the system belonging to the admin group

find / -group admin

Search all the .txt files of the jcarrillo user in the home directory.

find /home -user jcarrillo -iname “*.txt”

Now we go with searches with dates.

Perform search based on Dates

Search for modified files in the last 50 days.

find / -mtime 50

Search all files that were viewed or opened no matter if they were modified or not in the last 50 days.

find / -atime 50

Search the modified files between 50 and 100 days.

find / -mtime +50 -mtime -100

This last command is to see the files that were accessed in the previous hour.

find / -amin -60

Search for files and directories based on their size

Search for files that weigh exactly 50MB.

find / -size 50M

Search files between 50MB and 100MB

find / -size +50MB -size -100M

Search and delete files larger than 100MB (Be careful with this command you can have a hard time).

find / -size +100M -exec rm -rf {} \;

Search all .mp3 files with more than 10MB and delete them.

find / -type f -name *.mp3 -size +10M -exec rm {} \;