Difference between GNUWin32 and cygwin

Cygwin is a library that endeavours to make UNIX programs able to compile and run on Windows systems with minimal or no modifications, and a comprehensive set of packaged UNIX tools and applications compiled with this library. It is almost a complete wrapper around Windows. It includes an X server and an awful lot of the programs that you can expect to find in a Linux distribution. It is great for people who want to learn or use the UNIX command line in Windows.

MSYS is mostly a port of the UNIX tools necessary to build GNU style packages (with a configure etc) on Windows systems with the MinGW compiler. It uses a variant of the Cygwin library modified to sacrifice some compatibility for efficiency, and is more Windows-friendly.

GnuWin32 is simply a port of some of the GNU tools to Windows. Like MSYS, it uses msvcrt.dll, as well as an additional library to provide some UNIX compatibility functions. Its main purpose appears to be to allow Windows programs and batch files to use some of the GNU programs and libraries directly.

For the most part, they all provide UNIX programs on Windows, but there are many subtle differences, including:

• Intent. Cygwin is for people who want to use UNIX on their Windows OS. MSYS is for people who want to build Windows programs using the GNU/UNIX build tools. GnuWin32 is a port of individual GNU programs and libraries to Windows.
• Text files, particularly line endings. Cygwin lets you use CR/LF or LF. MSYS expects LF line endings. GnuWin32 programs expect CR/LF line endings.
• Supplied programs. In particular, Cygwin has a lot more packages, and GnuWin32 doesn't provide any shells.

As for git, it is available with Cygwin - this version can be used in a Windows directory (accessible under /cygdrive). Also, as mentioned, there is msysgit.

Michael Slade is correct. I would like to talk about the typical usage environment.

For practical reasons I use gnuwin as a light backend for stuff only remotely related to POSIX environments while cygwin is more of a full blown POSIX and even a very gnunixish environment.

Also gnuwin tends to become bloated when installing lots of tools because the executables are often using statically linked libraries. Cygwin on the other hand delivers a ton of dynamical libraries and rather small executables. So if you only need a few executables then gnuwin needs less resources. If you need a complex environment then cygwin will be more efficient.

gnuwin is also often slightly outdated, offers few software, no package/update-manager. It is a basic shell environment. No ssh, no gcc, vim, no perl, no sql - you can get these from other sources but how these cooperate is hard to predict. Cygwin fixes all above problems.

In other words, gnuwin is great for the occasional installer, for just putting du, find and sort in your $PATH. To do some real POSIX work use cygwin.

I once had a second Linux workstation, then a Linux VM running next to my windows system. Cygwin made them obsolet. It is good enough for a ton of things while saving tons of resources in comparison to a dedicated computer or a VM.