Using POSIX (Portable Operating System Interface [for Unix])

POSIX (Portable Operating System Interface [for Unix])  - http://en.wikipedia.org/wiki/POSIX

Cygwin - Cygwin is -

• a collection of tools which provide a Linux look and feel environment for Windows.
• a DLL (cygwin1.dll) which acts as a Linux API layer providing substantial Linux API functionality. 

more details for cygwin can be found in the below link - http://www.cygwin.com/


Setting path in Cygwin - http://cygwin.com/faq-nochunks.html#faq.using.path
Converting windows & unix paths - http://cygwin.com/faq-nochunks.html#faq.using.converting-paths
Why not install Cygwin in c - http://cygwin.com/faq-nochunks.html#faq.setup.c
Updating home variable - http://cygwin.com/faq-nochunks.html#faq.setup.home
Registry information of cygwin - http://cygwin.com/faq-nochunks.html#faq.setup.registry
Checking Cygwin version - http://cygwin.com/faq-nochunks.html#faq.what.version
Accessing drives using Cygwin - http://cygwin.com/faq-nochunks.html#faq.using.accessing-drives
Copy and paste in Cygwin - http://cygwin.com/faq-nochunks.html#faq.using.copy-and-paste
How does Cygwin work - http://cygwin.com/faq-nochunks.html#faq.api.everything
Updating log on information - http://cygwin.com/faq-nochunks.html#faq.setup.name-with-space

Cygwin/X "X Windows - on Windows!" -  More info about it can be found at below link - http://x.cygwin.com/
http://x.cygwin.com/screenshots/