Just how can I set up Cygwin to instantly upgrade and also download and install without the GUI?
Cygwin : Unix : : Peaches : Trombone (that got on my GRE ;)
Given just how dramatic Cygwin changes can be, I would certainly be actually skeptical of having it done without my specific authorization. If you are bold, you can invoke cron to run whatever upgrade manuscript you could pick.
If you were seeking the unwell - recorded
setup.exe --quiet-mode for neglected procedure, there it is.