The find command is a powerful and versatile utility in Linux and Unix-like operating systems used for searching files and directories within a directory hierarchy. It allows users to specify various criteria such as name, type, size, modification time, and permissions to locate specific files.

Find Files by Case-Insensitive Extension

This command searches for files with a case-insensitive extension, such as .jpg, .JPG, and .jpG. The -iname option performs a case-insensitive name match.

find . -iname '*.jpg'

Find Directories

To find only directories, use the -type d option. This will list all subdirectories within the specified path.

find . -type d

Find Regular Files

To find only regular files (excluding directories, symbolic links, etc.), use the -type f option.

find . -type f

Find Files by Octal Permissions

You can find files that match a specific octal permission mode using the -perm option. For example, to find files with 777 permissions:

find . -type f -perm 777

Find Files with Setuid Bit Set

This command finds files with the setuid bit set, which is often used for security-related executables. The -xdev option prevents crossing filesystem boundaries.

find . -xdev \( -perm -4000 \) -type f -print0 | xargs -0 ls -l

A more efficient and recommended approach using -printf to avoid external commands like ls:

find -perm -4000 -type f -print0 | xargs -I '{}' -0 \ls -l '{}'

Find and Remove Files by Extension

To find and remove files with a specific extension, like .txt, you can use the -exec rm {} \; option. However, a more efficient method is to use the built-in -delete action.

find [PATH] -name '*.txt' -delete

Find Files and Search for Strings

Combine find with grep to search for a specific string within files that match certain criteria.

find ./path/ -name '*.txt' | xargs grep 'string'

Find Files by Size

Locate files larger than a specified size. For example, to find files larger than 5 MB:

find . -size +5M -type f -print0 | xargs -0 ls -Ssh | sort -z

To find files larger than 2 MB and list them with human-readable sizes:

find . -type f -size +20000k -exec ls -lh {} \; | awk '{ print $9 ": " $5 }'

A faster alternative using -printf:

find -type f -size +20000k -printf '%s %P\n' |
    awk "{printf(\"%'dM %s\n\", \$1 / (1024 * 1024), \$2)}"

Find Files by Modification Time

Find files modified more than a certain number of days ago. For instance, to find files modified more than 7 days ago:

find . -type f -mtime +7d -ls

Find Symbolic Links

Search for symbolic links owned by a specific user.

find -type l -user [NAME] -ls

Delete Empty Directories

Efficiently search for and delete empty directories using the -empty and -delete options.

find -type d -empty -delete

Find Directories by Name and Depth

Search for directories named build up to a maximum depth of 2 levels.

find . -maxdepth 2 -name build -type d

Find Files Excluding Specific Directories

Find all files that are not within a .git directory. The -not or escaped ! operator is used for negation.

find . \! -iwholename '*.git*' -type f

Find Files with the Same Inode

Locate all files that share the same inode number as a given file, indicating they are hard links.

find . -type f -samefile [FILE] 2>/dev/null

Modify File Permissions

Find all files in the current directory and modify their permissions using -exec chmod.

find . -type f -exec chmod 644 {} \;

Edit Files with Vim

Find files with a specific extension (e.g., .txt) and open them all for editing with vim using -exec with + for efficiency.

find . -iname '*.txt' -exec vim {} \+

Rename File Extensions

Find files with one extension (e.g., .png) and rename them to another (e.g., .jpg) using a bash script within -exec. It's crucial to use \; here.

find . -type f -iname '*.png' -exec bash -c 'mv "$0" "${0%.*}.jpg"' {} \;

Delete Multiple File Types

Use logical operators like -or with grouping to delete files of multiple specified extensions.

find \( -iname "*.jpg" -or -iname "*.sfv" -or -iname "*.xspf" \) -type f -delete

List Executable Files by Basename

List the basenames of all executable files found within the directories specified in the PATH environment variable.

find ${PATH//:/ } -type f -executable -printf "%P\n"

External Resources

• Linux find Manual Page
• GNU Findutils Documentation
• Stack Overflow: find tag