I'm just going to merge this, since I want to get a github/github PR open today that bumps this gem. If there's any feedback, I can do a separate PR here and update the github/github PR.

This apparently is a linux vs. OS X nuance? Is that a openssl version thing?

Could be. Apparently on macOS, openssl is actually provided by LibreSSL from OpenBSD, where as on Linux, it's regular OpenSSL

I tested this on a linux host and see the prompt there too. I'm wondering if this might be a TTY thing or some environment variable being set. Here's a simple reproduction case if anyone wants to experiment

OpenSSL::PKey::EC.new(OpenSSL::PKey::EC.new('secp256k1').tap(&:generate_key).to_pem(OpenSSL::Cipher::AES.new(128, :CBC), 'aaaa'))

I tested this on a linux host and see the prompt there too

I thought this was a linux only thing that was happening in the first place? I think I'm confused 😄