A Comprehensive Guide to Using the fd File Search Tool

This article is part of HelloGitHub’s "Explaining Open‑Source Projects" series and presents fd, a fast, user‑friendly alternative to the Unix find command written in Rust.

1. fd Overview

fd is a cross‑platform command‑line tool that offers colorful output and powerful search capabilities. It is built with Rust, giving it performance comparable to C++ while providing a modern, ergonomic interface.

2. Installing fd

fd can be installed via package managers on macOS, Linux, and Windows, or built from source using Cargo.

2.1 One‑click installation (Homebrew)

$ brew install fd

Upgrade with:

$ brew upgrade fd

2.2 Building from source

$ git clone https://github.com/sharkdp/fd.git
$ cd fd
$ cargo install --path .

2.3 Viewing help

After installation, run fd -h or fd --help to see usage information.

$ fd -h
fd 8.2.1

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

FLAGS:
    -H, --hidden            Search hidden files and directories
    -I, --no-ignore         Do not respect .gitignore files
    -s, --case-sensitive    Enforce case‑sensitive matching
    -i, --ignore-case       Ignore case (smart case by default)
    -F, --fixed-strings     Treat pattern as a literal string
    -a, --absolute-path     Show absolute paths
    -L, --follow            Follow symlinks
    -p, --full-path         Search the full path
    -0, --print0            Separate results with a null character
    -h, --help              Print help information
    -V, --version           Print version information

OPTIONS:
    -d, --max-depth <depth>        Set maximum search depth
    -t, --type <filetype>...       Filter by file type (f, d, l, x, e, s, p)
    -e, --extension <ext>...      Filter by file extension
    -x, --exec <cmd>...            Execute a command for each result
    -E, --exclude <pattern>...    Exclude entries matching a glob pattern
    -c, --color <when>            When to use color (never, auto, always)
    -j, --threads <num>           Number of threads to use
    -S, --size <size>...           Filter by file size
    ...

3. Quick Start Demonstrations

A sample directory structure is created to illustrate various fd commands.

.
├── .hg
│   ├── HelloDjango.md
│   ├── HelloRust.md
│   ├── HelloVue.md
│   └── HelloZooKeeper.md
├── dir1
│   ├── Hello.java
│   ├── World.java
│   └── dir2
│       ├── demo.py
│       ├── demo1.py
│       ├── dir3
│       │   ├── fd_demo.rs
│       │   └── fd_help.rs
│       └── sss.py
├── hello_fd.md
├── hello_java.md
├── java
│   ├── Hello.java
│   └── World.java
├── my_java.txt
├── python
│   ├── demo.py
│   ├── demo1.py
│   └── sss.py
└── rust
    ├── fd_demo.rs
    └── fd_help.rs

3.1 Simple search

$ fd Hello
dir1/Hello.java
java/Hello.java

3.2 Include hidden files

$ fd -H Hello
.hg/HelloDjango.md
.hg/HelloRust.md
.hg/HelloVue.md
.hg/HelloZooKeeper.md
dir1/Hello.java
java/Hello.java

3.3 Case handling

$ fd -i Hello
dir1/Hello.java
hello_fd.md
hello_java.md
java/Hello.java

$ fd -s hello
hello_fd.md
hello_java.md

3.4 Absolute paths

$ fd -a Hello
/Users/junjiexun/fd_test/dir1/Hello.java
/Users/junjiexun/fd_test/java/Hello.java

3.5 List details

$ fd -l hello
-rw-r--r-- 1 junjiexun staff 0B 3 1 18:42 dir1/Hello.java
-rw-r--r-- 1 junjiexun staff 0B 3 1 18:37 hello_fd.md
...

3.6 Search full path

$ fd -p xun
dir1
dir1/Hello.java
...

3.7 Include .gitignore files

$ fd -I java
dir1/Hello.java
...

4. Advanced Search Options

4.1 Depth limit

$ fd -d 3 rs
rust/fd_demo.rs
rust/fd_help.rs

4.2 File type filtering

$ fd -t l
softdir3
sss.py

4.3 Extension filtering

$ fd -e md
hello_fd.md
hello_java.md

4.4 Excluding patterns

$ fd -E '*s*'
(dir1 and other entries without 's' in their names)

4.5 Owner filtering

$ fd -l -o junjiexun
drwxr-xr-x 5 junjiexun staff 160B 3 1 18:42 dir1
...

4.6 Executing commands on results

$ fd java -X rm -rf   # dangerous, for demo only
$ fd py -X vim

4.7 Regular expressions and glob patterns

$ fd '^s.*'
(dir1/dir2/sss.py, python/sss.py, softdir3, sss.py)

$ fd -g 's*'
(dir1/dir2/sss.py, python/sss.py, softdir3, sss.py)

5. Conclusion

fd is a simple, fast, and user‑friendly command‑line file search tool; its open‑source nature and Rust implementation make it an excellent example for learning system‑level programming while greatly improving everyday search workflows.