i have found some commands of linux are not working in cygwin..
but most unix commands are working ..
does cygwin support linux fully or is there any better software avaliable freely
What do you really need on cygwin?
And what commands are missing? Do you mean there's a bug in bash or an application is not present?
cygwin is actually a linux system running on top of windows and among others it also includes the X server, rpm manager and well everything, actually there is a version of the entire kde system with konqueror, koffice and all of those little kde apps that can be installed under cygwin
i have found some commands of linux are not working in cygwin..
but most unix commands are working ..
does cygwin support linux fully or is there any better software avaliable freely
Some of commands you said are not working, because some of them are not build-in command, there are often writen by others and installed on the linux system. If your cygwin has not installed them, the commands will not work as you have said.
So I think that cygwin can support linux fully, and you can install software if you want to use some other commands.