fd/README.md
2017-10-25 22:43:36 +02:00

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fd

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fd is a simple, fast and user-friendly alternative to find.

While it does not seek to mirror all of find's powerful functionality, it provides sensible (opinionated) defaults for 80% of the use cases.

Features

  • Convenient syntax: fd PATTERN instead of find -iname '*PATTERN*'.
  • Colorized terminal output (similar to ls).
  • It's fast (see benchmarks below).
  • 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.
  • Regular expressions.
  • Unicode-awareness.
  • The command name is 50% shorter* than find :-).
  • Parallel command execution with a syntax similar to GNU Parallel.

Demo

Demo

Benchmark

Let's search my home folder for files that end in [0-9].jpg. It contains ~150.000 subdirectories and about a million files. For averaging and statistical analysis, I'm using bench. All benchmarks are performed for a "warm cache". Results for a cold cache are similar.

Let's start with find:

find ~ -iregex '.*[0-9]\.jpg$'

time                 6.265 s    (6.127 s .. NaN s)
                     1.000 R²   (1.000 R² .. 1.000 R²)
mean                 6.162 s    (6.140 s .. 6.181 s)
std dev              31.73 ms   (0.0 s .. 33.48 ms)

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

find ~ -iname '*[0-9].jpg'

time                 2.866 s    (2.754 s .. 2.964 s)
                     1.000 R²   (0.999 R² .. 1.000 R²)
mean                 2.860 s    (2.834 s .. 2.875 s)
std dev              23.11 ms   (0.0 s .. 25.09 ms)

Now let's try the same for fd. Note that fd always performs a regular expression search. The options --hidden and --no-ignore are needed for a fair comparison, otherwise fd does not have to traverse hidden folders and ignored paths (see below):

fd --hidden --no-ignore '.*[0-9]\.jpg$' ~

time                 892.6 ms   (839.0 ms .. 915.4 ms)
                     0.999 R²   (0.997 R² .. 1.000 R²)
mean                 871.2 ms   (857.9 ms .. 881.3 ms)
std dev              15.50 ms   (0.0 s .. 17.49 ms)

For this particular example, fd is approximately seven times faster than find -iregex and about three times faster than find -iname. By the way, both tools found the exact same 14030 files 😄.

Finally, let's run fd without --hidden and --no-ignore (this can lead to different search results, of course):

fd '[0-9]\.jpg$' ~

time                 159.5 ms   (155.8 ms .. 165.3 ms)
                     0.999 R²   (0.996 R² .. 1.000 R²)
mean                 158.7 ms   (156.5 ms .. 161.6 ms)
std dev              3.263 ms   (2.401 ms .. 4.298 ms)

Note: This is one particular benchmark on one particular machine. While I have performed quite a lot of different tests (and found consistent results), things might be different for you! I encourage everyone to try it out on their own.

Concerning fd's speed, the main credit goes to the regex and ignore crates that are also used in ripgrep (check it out!).

Colorized output

fd can colorize files by extension, just like ls. In order for this to work, the environment variable LS_COLORS has to be set. Typically, the value of this variable is set by the dircolors command which provides a convenient configuration format to define colors for different file formats. On most distributions, LS_COLORS should be set already. If you are looking for alternative, more complete (and more colorful) variants, see here or here.

Parallel command execution

If the -x/--exec option is specified alongside a command template, a job pool will be created for executing commands in parallel for each discovered path as the input. 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).
  • {//}: Uses the parent of the discovered path (documents/images).
  • {/.}: Uses the basename, with the extension removed (party).
# Convert all jpg files to png files
fd -e jpg -x 'convert {} {.}.png'

# Unpack all zip files (if no placeholder is given, the path is appended):
fd -e zip -x unzip

# Convert all flac files into opus files:
fd -e flac -x 'ffmpeg -i {} -c:a libopus {.}.opus'

Install

With Rust's package manager cargo, you can install fd via:

cargo install fd-find

Note that rust version 1.19.0 or later is required. The release page of this repository also includes precompiled binaries for Linux.

On macOS, you can use Homebrew:

brew install fd

On Arch Linux, you can install the package from the official repos:

pacman -S fd-rs

On NixOS, or any Linux distro you can use Nix:

nix-env -i fd

On Windows, you can download the pre-built binaries from the Release page.

Development

git clone https://github.com/sharkdp/fd

# Build
cd fd
cargo build

# Run unit tests and integration tests
cargo test

# Install
cargo install

Command-line options

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

FLAGS:
    -H, --hidden            Search hidden files and directories
    -I, --no-ignore         Do not respect .(git)ignore files
    -s, --case-sensitive    Case-sensitive search (default: smart case)
    -i, --ignore-case       Case-insensitive search (default: smart case)
    -a, --absolute-path     Show absolute instead of relative paths
    -L, --follow            Follow symbolic links
    -p, --full-path         Search full path (default: file-/dirname only)
    -0, --print0            Separate results by the null character
    -h, --help              Prints help information
    -V, --version           Prints version information

OPTIONS:
    -d, --max-depth <depth>       Set maximum search depth (default: none)
    -t, --type <filetype>         Filter by type: f(ile), d(irectory), (sym)l(ink)
    -e, --extension <ext>         Filter by file extension
    -x, --exec <cmd>              Execute the given command for each search result
    -E, --exclude <pattern>...    Exclude entries that match the given glob pattern.
    -c, --color <when>            When to use colors: never, *auto*, always
    -j, --threads <num>           Set number of threads to use for searching &
                                  executing

ARGS:
    <pattern>    the search pattern, a regular expression (optional)
    <path>       the root directory for the filesystem search (optional)

Tutorial

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

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.

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

Specifying the root directory

If we want so 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

Running fd without any arguments

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

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

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 --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).

Using fd with xargs or parallel

If we want to run a command on all search results, we can pipe the output to xargs:

> fd -0 -e rs | xargs -0 wc -l

Here, the -0 option tells fd to separate search results by the NULL character (instead of . newlines) In the same way, the -0 option of xargs tells it to read the input in this way .