fd

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fd is a program to find entries in your filesystem. It is a simple, fast and user-friendly alternative to find. While it does not aim to support all of find's powerful functionality, it provides sensible (opinionated) defaults for a majority of use cases.

Installation • How to use • Troubleshooting

Features

• Intuitive syntax: fd PATTERN instead of find -iname '*PATTERN*'.
• Regular expression (default) and glob-based patterns.
• Very fast due to parallelized directory traversal.
• Uses colors to highlight different file types (same as ls).
• Supports parallel command execution
• Smart case: the search is case-insensitive by default. It switches to case-sensitive if the pattern contains an uppercase character*.
• Ignores hidden directories and files, by default.
• Ignores patterns from your .gitignore, by default.
• The command name is 50% shorter* than find :-).

Demo

How to use

First, to get an overview of all available command line options, you can either run fd -h for a concise help message or fd --help for a more detailed version.

Simple search

fd is designed to find entries in your filesystem. The most basic search you can perform is to run fd with a single argument: the search pattern. For example, assume that you want to find an old script of yours (the name included netflix):

> fd netfl
Software/python/imdb-ratings/netflix-details.py

If called with just a single argument like this, fd searches the current directory recursively for any entries that contain the pattern netfl.

Regular expression search

The search pattern is treated as a regular expression. Here, we search for entries that start with x and end with rc:

> cd /etc
> fd '^x.*rc$'
X11/xinit/xinitrc
X11/xinit/xserverrc

The regular expression syntax used by fd is documented here.

Specifying the root directory

If we want to search a specific directory, it can be given as a second argument to fd:

> fd passwd /etc
/etc/default/passwd
/etc/pam.d/passwd
/etc/passwd

List all files, recursively

fd can be called with no arguments. This is very useful to get a quick overview of all entries in the current directory, recursively (similar to ls -R):

> cd fd/tests
> fd
testenv
testenv/mod.rs
tests.rs

If you want to use this functionality to list all files in a given directory, you have to use a catch-all pattern such as . or ^:

> fd . fd/tests/
testenv
testenv/mod.rs
tests.rs

Searching for a particular file extension

Often, we are interested in all files of a particular type. This can be done with the -e (or --extension) option. Here, we search for all Markdown files in the fd repository:

> cd fd
> fd -e md
CONTRIBUTING.md
README.md

The -e option can be used in combination with a search pattern:

> fd -e rs mod
src/fshelper/mod.rs
src/lscolors/mod.rs
tests/testenv/mod.rs

Searching for a particular file name

To find files with exactly the provided search pattern, use the -g (or --glob) option:

> fd -g libc.so /usr
/usr/lib32/libc.so
/usr/lib/libc.so

Hidden and ignored files

By default, fd does not search hidden directories and does not show hidden files in the search results. To disable this behavior, we can use the -H (or --hidden) option:

> fd pre-commit
> fd -H pre-commit
.git/hooks/pre-commit.sample

If we work in a directory that is a Git repository (or includes Git repositories), fd does not search folders (and does not show files) that match one of the .gitignore patterns. To disable this behavior, we can use the -I (or --no-ignore) option:

> fd num_cpu
> fd -I num_cpu
target/debug/deps/libnum_cpus-f5ce7ef99006aa05.rlib

To really search all files and directories, simply combine the hidden and ignore features to show everything (-HI) or use -u/--unrestricted.

Matching the full path

By default, fd only matches the filename of each file. However, using the --full-path or -p option, you can match against the full path.

> fd -p -g '**/.git/config'
> fd -p '.*/lesson-\d+/[a-z]+.(jpg|png)'

Command execution

Instead of just showing the search results, you often want to do something with them. fd provides two ways to execute external commands for each of your search results:

• The -x/--exec option runs an external command for each of the search results (in parallel).
• The -X/--exec-batch option launches the external command once, with all search results as arguments.

Examples

Recursively find all zip archives and unpack them:

fd -e zip -x unzip

If there are two such files, file1.zip and backup/file2.zip, this would execute unzip file1.zip and unzip backup/file2.zip. The two unzip processes run in parallel (if the files are found fast enough).

Find all *.h and *.cpp files and auto-format them inplace with clang-format -i:

fd -e h -e cpp -x clang-format -i

Note how the -i option to clang-format can be passed as a separate argument. This is why we put the -x option last.

Any positional arguments after -x belong to the command template, not to fd itself. If you also want to pass a pattern or search path, put -x last:

fd pattern path -x echo

Find all test_*.py files and open them in your favorite editor:

fd -g 'test_*.py' -X vim

Note that we use capital -X here to open a single vim instance. If there are two such files, test_basic.py and lib/test_advanced.py, this will run vim test_basic.py lib/test_advanced.py.

To see details like file permissions, owners, file sizes etc., you can tell fd to show them by running ls for each result:

fd … -X ls -lhd --color=always

This pattern is so useful that fd provides a shortcut. You can use the -l/--list-details option to execute ls in this way: fd … -l.

The -X option is also useful when combining fd with ripgrep (rg) in order to search within a certain class of files, like all C++ source files:

fd -e cpp -e cxx -e h -e hpp -X rg 'std::cout'

Convert all *.jpg files to *.png files:

fd -e jpg -x convert {} {.}.png

Here, {} is a placeholder for the search result. {.} is the same, without the file extension. See below for more details on the placeholder syntax.

The terminal output of commands run from parallel threads using -x will not be interlaced or garbled, so fd -x can be used to rudimentarily parallelize a task run over many files. An example of this is calculating the checksum of each individual file within a directory.

fd -tf -x md5sum > file_checksums.txt

Placeholder syntax

The -x and -X options take a command template as a series of arguments (instead of a single string). If you want to add additional options to fd after the command template, you can terminate it with a \;.

For example, fd -x echo \; pattern path treats pattern path as fd arguments instead of passing them to echo. In practice, it is often clearer to write fd pattern path -x echo.

The syntax for generating commands is similar to that of GNU Parallel:

• {}: A placeholder token that will be replaced with the path of the search result (documents/images/party.jpg).
• {.}: Like {}, but without the file extension (documents/images/party).
• {/}: A placeholder that will be replaced by the basename of the search result (party.jpg).
• {//}: The parent of the discovered path (documents/images).
• {/.}: The basename, with the extension removed (party).

If you do not include a placeholder, fd automatically adds a {} at the end.

Parallel vs. serial execution

For -x/--exec, you can control the number of parallel jobs by using the -j/--threads option. Use --threads=1 for serial execution.

Excluding specific files or directories

Sometimes we want to ignore search results from a specific subdirectory. For example, we might want to search all hidden files and directories (-H) but exclude all matches from .git directories. We can use the -E (or --exclude) option for this. It takes an arbitrary glob pattern as an argument:

> fd -H -E .git …

We can also use this to skip mounted directories:

> fd -E /mnt/external-drive …

.. or to skip certain file types:

> fd -E '*.bak' …

To make exclude-patterns like these permanent, you can create a .fdignore file. They work like .gitignore files, but are specific to fd. For example:

> cat ~/.fdignore
/mnt/external-drive
*.bak

[!NOTE] fd also supports .ignore files that are used by other programs such as rg or ag.

If you want fd to ignore these patterns globally, you can put them in fd's global ignore file. This is usually located in ~/.config/fd/ignore in macOS or Linux, and %APPDATA%\fd\ignore in Windows.

You may wish to include .git/ in your fd/ignore file so that .git directories, and their contents are not included in output if you use the --hidden option.

Deleting files

You can use fd to remove all files and directories that are matched by your search pattern. If you only want to remove files, you can use the --exec-batch/-X option to call rm. For example, to recursively remove all .DS_Store files, run:

> fd -H '^\.DS_Store$' -tf -X rm

If you are unsure, always call fd without -X rm first. Alternatively, use rms "interactive" option:

> fd -H '^\.DS_Store$' -tf -X rm -i

If you also want to remove a certain class of directories, you can use the same technique. You will have to use rms --recursive/-r flag to remove directories.

[!NOTE] There are scenarios where using fd … -X rm -r can cause race conditions: if you have a path like …/foo/bar/foo/… and want to remove all directories named foo, you can end up in a situation where the outer foo directory is removed first, leading to (harmless) "'foo/bar/foo': No such file or directory" errors in the rm call.

Command-line options

This is the output of fd -h. To see the full set of command-line options, use fd --help which also includes a much more detailed help text.

Usage: fd [OPTIONS] [pattern [path]...]

Arguments:
  [pattern]  the search pattern (a regular expression, unless '--glob' is used; optional)
  [path]...  the root directories for the filesystem search (optional)

Options:
  -H, --hidden                     Search hidden files and directories
  -I, --no-ignore                  Do not respect .(git|fd)ignore files
  -s, --case-sensitive             Case-sensitive search (default: smart case)
  -i, --ignore-case                Case-insensitive search (default: smart case)
  -g, --glob                       Glob-based search (default: regular expression)
  -a, --absolute-path              Show absolute instead of relative paths
  -l, --list-details               Use a long listing format with file metadata
  -L, --follow                     Follow symbolic links
  -p, --full-path                  Search full abs. path (default: filename only)
  -d, --max-depth <depth>          Set maximum search depth (default: none)
  -E, --exclude <glob>             Exclude entries that match the given glob pattern
  -t, --type <filetype>            Filter by type: file (f), directory (d/dir), symlink (l),
                                   executable (x), empty (e), socket (s), pipe (p), char-device
                                   (c), block-device (b)
  -e, --extension <ext>            Filter by extension
  -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)
  -o, --owner <user:group>         Filter by owning user and/or group
      --format <fmt>               Print results according to template
  -x, --exec <cmd>...              Execute a command for each search result
  -X, --exec-batch <cmd>...        Execute a command with all search results at once
  -c, --color <when>               When to use colors [default: auto] [possible values: auto,
                                   always, never]
      --hyperlink[=<when>]         Add hyperlinks to output paths [default: never] [possible
                                   values: auto, always, never]
      --ignore-contain <name>      Ignore directories containing the named entry
  -h, --help                       Print help (see more with '--help')
  -V, --version                    Print version

Note that options can be given after the pattern and/or path as well.

Benchmark

Let's search my home folder for files that end in [0-9].jpg. It contains ~750,000 subdirectories and about a 4 million files. For averaging and statistical analysis, I'm using hyperfine. The following benchmarks are performed with a "warm"/pre-filled disk-cache (results for a "cold" disk-cache show the same trends).

Let's start with find:

Benchmark 1: find ~ -iregex '.*[0-9]\.jpg$'
  Time (mean ± σ):     19.922 s ±  0.109 s
  Range (min … max):   19.765 s … 20.065 s

find is much faster if it does not need to perform a regular-expression search:

Benchmark 2: find ~ -iname '*[0-9].jpg'
  Time (mean ± σ):     11.226 s ±  0.104 s
  Range (min … max):   11.119 s … 11.466 s

Now let's try the same for fd. Note that fd performs a regular expression search by default. The options -u/--unrestricted option is needed here for a fair comparison. Otherwise fd does not have to traverse hidden folders and ignored paths (see below):

Benchmark 3: fd -u '[0-9]\.jpg$' ~
  Time (mean ± σ):     854.8 ms ±  10.0 ms
  Range (min … max):   839.2 ms … 868.9 ms

For this particular example, fd is approximately 23 times faster than find -iregex and about 13 times faster than find -iname. By the way, both tools found the exact same 546 files :smile:.

Note: This is one particular benchmark on *one particula