title: How do I tell if OpenPGP encryption is symmetric or asymmetric?
body: <p>Is there a way to tell if things encrypted via the GNU Privacy Guard are symmetric or asymmetric (without decrypting them or already knowing to start with)? How?</p>
  
  <p>Anyway (for those who want to know what I'm doing), I used Python 3.x to program a GUI-based IDE of sorts that can open symmetrically encrypted files (and save them, too). It can open asymmetrically encrypted files (enter the passphrase to use your secret key instead of the passphrase to decrypt a symmetrically encrypted file). However, it doesn't know they're asymmetric and will overwrite them with symmetrically encrypted files if saved. It would be nice to be able to save them asymmetrically, too. My editor uses the <code>gpg</code> command-line program on Linux (no <code>gpg</code> libraries or anything like that).</p>
  
  <p>I could have a checkbox on the password prompt for asymmetric encryption, but I'd rather not make it so it has to be a manual thing for the user.</p>
  
  <p>For my own personal files, I could add some kind of marker to the saved files to distinguish, but I want it to be able to open them correctly even if they weren't created in my IDE.</p>
  
  <p>I know there's a question with a similar title, but the question asked in the body is fundamentally different.</p>