Linux Find Command

Linux Find Command

Basic examples

1. List all files in current and sub directories

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$ find
.
./abc.txt
./subdir
./subdir/how.php
./cool.php

The command is same as the following

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$ find .
$ find . -print

2. Search specific directory or path

The following command searches for files by their name.

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$ find ./test -name "abc.txt"
./test/abc.txt

We can also use wildcards

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$ find ./test -name "*.php"
./test/subdir/how.php
./test/cool.php

It is often useful to ignore the case when searching for file names. To ignore the case, just use the “iname” option instead of the “name” option.

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$ find ./test -iname "*.Php"
./test/subdir/how.php
./test/cool.php

3. Limit depth of directory traversal

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$ find ./test -maxdepth 2 -name "*.php"
./test/subdir/how.php
./test/cool.php

$ find ./test -maxdepth 1 -name *.php
./test/cool.php

Just like maxdepth there is an option called mindepth which does what the name suggests, that is, it will go atleast N level deep before searching for the files.

4. Invert match

It is also possible to search for files that do not match a given name or pattern. This is helpful when we know which files to exclude from the search.

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$ find ./test -not -name "*.php"
./test
./test/abc.txt
./test/subdir

So in the above example we found all files that do not have the extension of php, either non-php files. The find command also supports the exclamation mark inplace of not.
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find ./test ! -name "*.php"

5. Combine multiple search criterias

It is possible to use multiple criterias when specifying name and inverting. For example

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$ find ./test -name 'abc*' ! -name '*.php'
./test/abc.txt
./test/abc

The above find command looks for files that begin with abc in their names and do not have a php extension. This is an example of how powerful search expressions can be build with the find command.

  • OR operator

When using multiple name criterias, the find command would combine them with AND operator, which means that only those files which satisfy all criterias will be matched. However if we need to perform an OR based matching then the find command has the “o” switch.

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$ find -name '*.php' -o -name '*.txt'
./abc.txt
./subdir/how.php
./abc.php
./cool.php

The above command search for files ending in either the php extension or the txt extension.

6. Search only files or only directories

Sometimes we want to find only files or only directories with a given name. Find can do this easily as well.

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$ find ./test -name "abc*"
./test/abc.txt
./test/abc

Only files
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$ find ./test -type f -name "abc*"
./test/abc.txt

Only directories
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$ find ./test -type d -name "abc*"
./test/abc

7. Search multiple directories together

So lets say you want to search inside 2 separate directories. Again, the command is very simple

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$ find ./test ./dir2 -type f -name "abc*"
./test/abc.txt
./dir2/abcdefg.txt

Check, that it listed files from 2 separate directories.

8. Find hidden files

Hidden files on linux begin with a period. So its easy to mention that in the name criteria and list all hidden files.

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$ find ~ -type f -name ".*"

Find files based on permissions

9. Find files with certain permissions

The find command can be used to find files with a specific permission using the “perm” option. The following command searches for files with the permission 0664

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$ find . -type f -perm 0664
./abc.txt
./subdir/how.php
./abc.php
./cool.php

This can be useful to find files with wrong permissions which can lead to security issues. Inversion can also be applied to permission checking.
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$ find . -type f ! -perm 0777
./abc.txt
./subdir/how.php
./abc.php
./cool.php

10. Find files with sgid/suid bits set

The “perm” option of find command accepts the same mode string like chmod. The following command finds all files with permission 644 and sgid bit set.

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# find / -perm 2644

11. Find readonly files

Find all Read Only files.

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$ find /etc -maxdepth 1 -perm /u=r
/etc
/etc/thunderbird
/etc/brltty
/etc/dkms
/etc/phpmyadmin

12. Find executable files

The following command will find executable files

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$ find /bin -maxdepth 2 -perm /a=x
/bin
/bin/preseed_command
/bin/mount
/bin/zfgrep
/bin/tempfile

Search Files Based On Owners and Groups

13. Find files belonging to particular user

To find all or single file called tecmint.txt under /root directory of owner root.

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$ find . -user bob
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./abc.txt
./abc
./subdir
./subdir/how.php
./abc.php

We could also specify the name of the file or any name related criteria along with user criteria

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$ find . -user bob -name '*.php'

Its very easy to see, how we can build up criteria after criteria to narrow down our search for matching files.

14. Search files belonging to group

Find all files that belong to a particular group.

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# find /var/www -group developer

Did you know you could search your home directory by using the ~ symbol ?
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$ find ~ -name "hidden.php"

15. Find files modified N days back

To find all the files which are modified 50 days back.

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# find / -mtime 50

16. Find files accessed in last N days

Find all files that were accessed in the last 50 days.

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# find / -atime 50

17. Find files modified in a range of days

Find all files that were modified between 50 to 100 days ago.

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# find / -mtime +50 –mtime -100

18. Find files changed in last N minutes.

Find files modified within the last 1 hour.

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$ find /home/bob -cmin -60

19. Files modified in last hour

To find all the files which are modified in last 1 hour.

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$ find / -mmin -60

20. Find Accessed Files in Last 1 Hour

To find all the files which are accessed in last 1 hour.

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# find / -amin -60

Search files and directories based on size

21. Find files of given size

To find all 50MB files, use.

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# find / -size 50M

22. Find files in a size range

To find all the files which are greater than 50MB and less than 100MB.

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

23. Find largest and smallest files

The find command when used in combination with the ls and sort command can be used to list out the largest files.
The following command will display the 5 largest file in the current directory and its subdirectory. This may take a while to execute depending on the total number of files the command has to process.

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$ find . -type f -exec ls -s {} \; | sort -n -r | head -5

Similary when sorted in ascending order, it would show the smallest files first
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$ find . -type f -exec ls -s {} \; | sort -n | head -5

24. Find empty files and directories

The following command uses the “empty” option of the find command, which finds all files that are empty.

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$ find /tmp -type f -empty

To file all empty directories use the type “d”.
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$ find ~/ -type d -empty

Some advanced operations

The find command not only finds files based on a certain criteria, it can also act upon those files using any linux command. For example, we might want to delete some files.

Here are some quick examples

25. List out the found files

Lets say we found files using find command, and now want to list them out as the ls command would have done. This is very easy.

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$ find . -exec ls -ld {} \;
drwxrwxr-x 4 enlightened enlightened 4096 Aug 11 19:01 .
-rw-rw-r-- 1 enlightened enlightened 0 Aug 11 16:25 ./abc.txt
drwxrwxr-x 2 enlightened enlightened 4096 Aug 11 16:48 ./abc
drwxrwxr-x 2 enlightened enlightened 4096 Aug 11 16:26 ./subdir
-rw-rw-r-- 1 enlightened enlightened 0 Aug 11 16:26 ./subdir/how.php
-rw-rw-r-- 1 enlightened enlightened 29 Aug 11 19:13 ./abc.php
-rw-rw-r-- 1 enlightened enlightened 0 Aug 11 16:25 ./cool.php

26. Delete all matching files or directories

The following command will remove all text files in the tmp directory.

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

The same operating can be carried out with directories, just put type d, instead of type f.

Lets take another example where we want to delete files larger than 100MB

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$ find /home/bob/dir -type f -name *.log -size +10M -exec rm -f {} \;

27. find all files excliude folder

The following command will find all files excliude venv folder

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$ find . | grep -v venv
$ find . | grep -v venv | grep -v pycache

Summary

So that was a quick tutorial on the linux find command. The find command is one of the most essential commands on the linux terminal, that enables searching of files very easy. Its a must of all system administrators. So learn it up. Have any questions ? Leave a comment below.