cFd

A fully custom terminal shell written in C — no bash, no PowerShell, no wrappers.

cFd is a from-scratch terminal shell built entirely in C. It has its own lexer, parser, AST, command dispatcher, line editor, history, tab completion, syntax highlighting, scripting engine, and 70+ built-in commands — none of it delegated to an existing shell.

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Download

Platform	File	Notes
Windows	cFd-1.0.0-windows.msi	MSI installer — adds cfd to PATH
macOS	cFd-1.0.0-macos.dmg	App bundle
Linux	cFd-1.0.0-linux-x86_64.tar.gz	Standalone binary

Or build from source — see Building.

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Features

• Custom line editor — arrow keys, Ctrl+A/E/K/U/W/Y, kill-ring
• Syntax highlighting — commands, strings, pipes, variables colored as you type
• Auto-suggest — ghost-text completion from history (→ to accept)
• Ctrl+R — incremental reverse history search
• Tab completion — commands and file paths with ~ expansion
• Multiline input — auto-detects incomplete if/while/pipeline and prompts for continuation
• Real pipes — cmd1 | cmd2 | cmd3 via dup/dup2 (no temp files)
• I/O redirection — >, >>, <, 2>, 2>&1
• Scripting — variables, if/elif/else, while, for, functions, source
• Variable expansion — $VAR, ${VAR}, $?, $#, $1..$N
• Aliases — alias/unalias
• Job control — &, jobs, bg, fg
• Ctrl+C forwarding — kills the running child process, not the shell
• Execution timer — shows elapsed time for commands taking >5s
• Smart prompt — exit code indicator, git branch, user, host, path
• Package manager — pkg install git via winget/scoop/apt/brew
• Built-in text editor — nano with search, cut/paste, save
• HTTP client — curl, wget (WinHTTP on Windows, sockets on Unix)
• Crypto — md5, sha256 implemented from scratch (RFC 1321, FIPS 180-4)
• Calculator — calc with trig, log, sqrt, pi, e, ans
• Themes — default, dark, minimal
• Cross-platform — Windows (Win32 API) and Unix (POSIX)

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Building

Requirements: GCC (MinGW on Windows), GNU Make

git clone https://github.com/saarors/cFd.git
cd cFd
make
./cfd          # Linux/macOS
cfd.exe        # Windows

make clean     # remove build artifacts
make tests     # build and run tests
make install   # install to /usr/local/bin (Unix)

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Built-in Commands

Filesystem

ls cd pwd mkdir rmdir rm cp mv cat touch stat find du df ln tree realpath chmod

Text Processing

echo grep wc sort head tail cut tr tee uniq diff base64 xargs column fold

System

help version exit clear date env export set unset alias source history which type read sleep uname whoami hostname uptime watch test

Process

ps kill jobs bg fg exec wait

Network

curl wget ping netstat ipconfig

Math

calc expr seq md5 sha256

Editor

nano — full terminal text editor (^X exit, ^S save, ^W search, ^K/^U cut/paste)

Package Manager

pkg install <name> pkg remove pkg search pkg list pkg info

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Scripting

# Variables
name="world"
echo "Hello, $name"

# If / elif / else
if test -f config.json
  echo "found"
else
  echo "not found"
fi

# While / For
for f in *.c
  echo "$f"
done

# Functions
function greet
  echo "Hello, $1!"
end
greet cFd

# Pipelines & redirection
ls -la | grep ".c" | sort | head -10 > sources.txt

RC file — ~/.cfdrc

alias ll="ls -la"
alias gs="git status"
export EDITOR=nano
theme=dark

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Prompt Customization

Escape	Meaning
\u	username
\h	hostname
\w	working directory
\g	git branch
\t	time HH:MM:SS
\e	exit code (red if non-zero)
\$	> green/red based on last exit
\n	newline

Default: \e\u@\h \w\$

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Architecture

source → lexer → tokens → parser → AST → dispatcher → builtin / external

cFd/
├── include/          # types, config, version
├── src/
│   ├── utils/        # mem, str, hash, list, path, log
│   ├── platform/     # Win32 + POSIX abstraction
│   ├── ui/           # color, themes, display, prompt
│   ├── parser/       # lexer, tokens, AST, parser
│   ├── input/        # readline, history, completion, keybinds
│   ├── io/           # streams, pipes, redirection
│   ├── scripting/    # variables, control flow, functions
│   ├── commands/     # registry, dispatcher
│   │   └── builtin/  # fs/ text/ sys/ process/ net/ math/ crypto/ editor/ pkg/
│   └── core/         # session, REPL, config, terminal
├── installer/
│   ├── windows/      # cfd.wxs (WiX MSI), cfd.nsi (NSIS)
│   └── macos/        # build_app.sh, Info.plist
├── .github/workflows/release.yml   # auto-build releases on git tag
├── docs/             # GitHub Pages website
└── tests/

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Releases

Installers are built automatically by GitHub Actions on every tagged release:

git tag v1.0.0
git push --tags

GitHub Actions builds cFd-*.msi (Windows), cFd-*.dmg (macOS), and cFd-*-linux.tar.gz in parallel and attaches them to the GitHub Release.

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License

MIT — see LICENSE

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Built from scratch in C · No bash · No PowerShell · No wrappers