Cygwin

Overview

Cygwin is a large open-source project that provides a Unix-like environment on Microsoft Windows, allowing Windows users to directly use commonly used Linux/Unix tools, shells, and programming environments in the command line without installing a virtual machine or dual-booting. It was initiated in 1995 by Red Hat employee Steve Chamberlain and is now maintained by the Cygwin Project (owned by Red Hat). Its official website is cygwin.com, and it is licensed under GPL v3 with exceptions (the core DLL is under LGPL). Simply put: Cygwin = cygwin1.dll (POSIX compatibility layer) + thousands of GNU/open-source packages ported to Windows (bash, gcc, make, git, vim, python, rsync, wget, openssh…).

History and Development

• October 1995: Steve Chamberlain (Cygnus Solutions, later acquired by Red Hat) released the first version. - 1996–1998: Added bash, gcc, and the GNU toolchain, becoming a complete Unix-like environment.
• 2000: Red Hat acquired Cygnus, and Cygwin was officially maintained by Red Hat.
• 2001: Introduced the setup.exe graphical installer (still in use today).
• 2013: Support for 64-bit Windows (starting with Cygwin 1.7.18).
• 2016: Released Cygwin 2.5, using UTF-8 by default, supporting Windows 10.
• 2022: Cygwin 3.4 series supports Windows 11 and ARM64 (experimental).
• October 2025: Cygwin 3.5.4 released: native ARM64, better Windows 11 24H2 compatibility, mintty upgrade.

Key Features

1. POSIX Compatibility Layer: cygwin1.dll provides Unix system calls such as fork, pipe, signal, select/poll, etc.
2. Number of Packages: Over 15,000 (including gcc, python3, git, vim, rsync, openssh, wget, curl, tmux, etc.). 3. Terminal: Mintty is used by default (supports 256 colors, true color, mouse, and scrollbars).
3. Shell: Bash is used by default; zsh, fish, tcsh, etc., can also be installed.
4. File System: Supports Unix permissions (chmod/chown), symbolic links, and paths such as /home and /tmp.
5. Compilers: All compilers are available, including gcc, clang, go, rust, python, and nodejs.
6. Package Manager: setup-x86_64.exe (graphical) or apt-cyg, cyg-apt (apt-like).
7. ARM64 Support: Native support for Windows on ARM (Surface Pro X, ThinkPad X13s, etc.) starting in 2025.
8. UTF-8 Default: UTF-8 is used by default across the entire system starting with version 3.4; no additional settings are required.
9. Interoperability with Windows: Can directly access C:\ (/cygdrive/c) and run... .exe, PowerShell, and WSL coexist.

Advantages and Limitations

Advantages

• Fully compatible with older versions of Windows (still supports Win7).
• Most complete software package (15,000+).
• Seamless interaction with Windows programs (can directly call exe).
• Supports ARM64 Windows.
• Long-term stability (30 years of history).

Limitations (compared to WSL)

• Slightly lower performance than native Linux and WSL2 (system call overhead).
• Poor fork() performance (slow copying of large processes).
• Some GUI programs require X Server (rarely used now).
• File permissions are limited on NTFS (requires cygserver).
• Large installation package size (basic installation approximately 2-3GB).

Summary

Cygwin is the oldest and most complete Unix-like environment on Windows, having evolved to version 3.5.4 in 2025, supporting Windows 11. Cygwin is a native ARM64 platform with default UTF-8 and over 15,000 software packages. It's particularly suitable for: developers who still need to use Windows but want to retain their Linux toolchain; users who need to compile Linux software, run bash scripts, and use rsync/ssh on Windows; and scenarios requiring a complete Unix toolchain on ARM64 Windows devices (such as the Surface Pro X). In short: Cygwin is no longer the only option, but it remains the most "authentic" Unix experience on Windows, especially unmatched in terms of compatibility and the number of software packages.