Find Files With the fd Command

Linux users typically rely upon the built-in find command to locate files and directories on their system. It provides a large number of powerful and useful options, but its default behavior often fails to provide intuitive results. The free open-source fd utility provides a user-friendly alternative to the find command. It is more efficient and easier to use, with default behavior that is better suited for the majority of searches. This guide compares the find and fd commands and explains how to use and install the fd command on Linux systems.

An Introduction to fd

As with the find command, the fd command allows users to find entries in their filesystem. The basic syntax for the command is fd <search_pattern>. Rather than being a complete replacement for find, fd focuses on simplicity, performance, and ease of use.

The fd command does not support every option that the find command does. However, it has a more intuitive syntax with sensible defaults, so users do not usually have to append additional options. For instance, a search in fd is only case sensitive if a capital letter is included in the search term. Otherwise, the search is case insensitive.

According to rigorous benchmark testing on Linux systems, fd generates results much more quickly than find does. It often takes only one-tenth as long to execute the same search and return the same results. fd achieves better performance due to its parallel tree traversal along with improved regex and ignore algorithms.

Key Differences Between fd vs find

Because the fd command has been optimized for everyday use, it behaves differently than find in certain situations. Here are some of the main differences between the two commands:

• By default, fd searches are based on directory name or filename. The -name or -iname options are not required, as they are often used when using the find command.
• Support for regular expressions is tightly integrated into fd.
• fd uses color output to highlight file types similar to the ls command.
• fd supports parallel command execution.
• Searches in fd are usually case-insensitive, but become case sensitive if a capital letter is included in the search term. The find command uses the -iname option to control this behavior.
• Default fd searches ignore hidden files and directories, as well as any patterns listed in the .gitignore file.

Install fd

The fd command is available as part of the default packages on most Linux distributions. Instructions for the most common systems are as follows.

Ubuntu / Debian

For release 19.04 and higher of Ubuntu, the fd application is available through APT. Ubuntu already has a package named fd, so the fd binary is referred to as fdfind. An alias must be added to use the fd command.

1. Install fd using APT.

   Note

   Use apt-get in place of apt on Debian distributions.

    sudo apt install fd-find
   

2. (Optional) Create an alias for fd that refers to fdfind. To start using the fd command immediately, use the alias command.

    alias fd=fdfind
   

3. (Optional) Add this entry to the bashrc file to make the alias permanent.

   File: ~/.bashrc

   1 2	alias fd=fdfind

RHEL Derivatives

On Red Hat-based distributions, fd can be installed using DNF. There is no requirement to create an alias.

dnf install fd-find

...
Installed:
  fd-find-8.1.1-3.fc33.x86_64

Complete!

Arch

On the Arch Linux distribution, the fd package can be installed from the official “pacman” repository.

pacman -S fd

Alpine

On the Alpine distribution, the fd package can be installed using apk.

apk add fd

How to Use fd

The fd command is very useful on its own but can be made even more useful by adding regular expressions and command options.

To see all of the available flags and options, along with usage instructions, use fd -h. The fd --help command provides even more detail about each option.

fd -h

fd 7.4.0

USAGE:
    fd [FLAGS/OPTIONS] [<pattern>] [<path>...]

FLAGS:
    -H, --hidden            Search hidden files and directories
...
    -V, --version           Prints version information

OPTIONS:
    -d, --max-depth <depth>            Set maximum search depth (default: none)
...
    -S, --size <size>...               Limit results based on the size of files.
        --changed-within <date|dur>    Filter by file modification time (newer than)
        --changed-before <date|dur>    Filter by file modification time (older than)

ARGS:
    <pattern>    the search pattern: a regular expression unless '--glob' is used (optional)
    <path>...    the root directory for the filesystem search (optional)

Note: `fd -h` prints a short overview while `fd --help` gives all details.

Basic Search Functionality

If fd is used without any arguments, it recursively displays all files and directories in the current working directory. This is very similar to the behavior of the ls -r command. However, fd is typically used with a parameter specifying the search pattern.

Use fd <search_pattern> to find all entries in the current directory that match the search pattern. An entry is considered to be a match if its name contains the search pattern. The command searches all subdirectories recursively, so it also displays any matching entries in any directory that has the current directory in its path.

fd backup

accounts/payroll/backup_file.sql
accounts/payroll/backup_files.sql
backup
backup/accounts/payroll/backup_file.sql
backup/accounts/payroll/backup_files.sql
mysqlbackup
mysqlbackup/backup_file.sql
mysqlbackup/backup_files.sql
wpbackup

To search in a specific directory other than the current one, provide the full path of the directory as the second argument. The command pattern for this type of search is fd <search_pattern> <target_dir>.

fd backup /usr

/usr/lib/mysql/plugin/component_mysqlbackup.so
...
/usr/src/linux-headers-5.4.0-86-generic/include/config/net/team/mode/activebackup.h

To list all files in a specific directory, use the wild card symbol . as the search pattern.

fd . ~/wpbackup/public_html/wp-content/themes/twentytwentyone

Advanced Search Features

The fd command also allows searches based on regular expressions, file extensions, exact file names, and hidden files.

Technically, every fd search uses regular expressions. However, the search pattern can be specified in a regex format. The following search looks for entries starting with an m and containing the substring back at any other position. For more information on the regular expression syntax, consult the regex documentation.

fd '^m.*back.*$'

mysqlbackup

The fd command can be used with the -e option to find files with a particular extension. In the example below, the command finds all SQL files.

fd -e sql

accounts/payroll/backup_file.sql
...
mysqlbackup/customer_file.sql

Typically, fd works in regexp mode and parses the search term as a regular expression. However, adding the -g option forces fd to perform a glob-based search. This causes it to only display entries that exactly match the search term. In the following search, the backup directory matches, but wpbackup does not perfectly match and is not listed.

fd -g backup

backup

Without any options, fd skips over hidden files and directories. These are entries that have names beginning with the . character. However, adding the -H option causes fd to include these entries in its search.

fd -H bash

.bash_history
.bash_logout
.bashrc

The -x option allows the results to be piped to another command. This is referred to as command execution. The format of the command is fd <search_term> -x <command_to_execute>. For instance, fd -e txt -x vim opens each file that matches the search criteria in Vim. To launch the command only once with the list of the files as a string of arguments, use -X instead. The {} token represents a placeholder for the filename in the target command. This allows for the execution of more complex commands. Consult the fd documentation for a full list of all placeholders.

In the following example, a backup copy is made of each txt file found by fd. The new file has the same name as the old file with .bak appended to the end. The -x option invokes the command for each matching entry.

fd -e txt -x cp {} {}.bak

For a full list of options, use fd --help or consult the fd GitHub page. Here are a few more options that might be useful:

• To search for a match on the full path of the file, as opposed to only the filename, use fd -p.
• The -I option includes both hidden files and those that match a pattern in the .gitignore directory.
• -E <exclude_string> excludes all entries matching the excluded string.
• -s is used to force fd to perform a case-sensitive search.
• The -t <filetype> option is used to filter entries by entry type. Some common types are f for file, d for the directory, l for symlink, and x for executable.
• The -d option is used to set the maximum search depth in terms of the number of levels of subdirectories.

Using fd With Other Programs

Because fd supports command execution, users can easily integrate other programs. For example, the output from fd can be piped to the as-tree program and represented in tree format. This is usually more useful than running the Linux tree command because fd has already pre-processed which files to display. To use the two programs together, run the following command.

fd backup | as-tree

.
├── accounts/payroll
│   ├── backup_file.sql
│   └── backup_files.sql
├── backup/accounts/payroll
│   ├── backup_file.sql
│   └── backup_files.sql
├── mysqlbackup
│   ├── backup_file.sql
│   └── backup_files.sql
└── wpbackup

For information on installing and using as-tree, consult the as-tree GitHub page.

The fd documentation also explains how fd can be used in conjunction with Emacs, the fzf fuzzy finder, and the menu builder rofi.

Conclusion

The fd command for Linux is an alternative to the built-in find command that is more intuitive and easier to use. fd runs more quickly and has intelligent defaults that align with the needs of most users. It can be installed on most Linux distributions and is usually part of the default package.

fd is not able to do everything the find command does, but it has a large number of options that allow users to refine their searches. By default, fd ignores hidden files and is case sensitive only when a capital letter is included in the search term. fd uses regular expressions in its searches, and has powerful regexp capabilities. The fd command also supports command execution, which allows the search results to serve as input for another program or command.

More Information

You may wish to consult the following resources for additional information on this topic. While these are provided in the hope that they will be useful, please note that we cannot vouch for the accuracy or timeliness of externally hosted materials.

• fd GitHub page