[cygwin] How can I change my Cygwin home folder after installation?

I happen to use cwRsync (Cygwin + Rsync for Windows) where cygwin comes bundled, and I couldn't find /etc/passwd.

And it kept saying

Could not create directory '/home/username/.ssh'.
...
Failed to add the host to the list of known hosts (/home/username/.ssh/known_hosts).

So I wrote a batch file which changed the HOME variable before running rsync. Something like:

set HOME=.
rsync /path1 user@host:/path2

And voila! The .ssh folder appeared in the current working dir, and rsync stopped annoying with rsa fingerprints.

It's a quick hotfix, but later you should change HOME to a more secure location.