/ Published in: Regular Expression
A Cygwin installation can be cloned by copying `/etc/setup/installed.db` and zeroing all version numbers, then running the installation utility. The following `sed` script will set the version of most packages to zero. Some non-standard version numbers will not be affected and have to be zeroed by hand.
URL: http://cygwin.com/ml/cygwin/2006-05/msg00753.html