Photo File Security

If I process a photo in Photoshop, save it as "read-only", then e-mail it to someone is there a way to LOCK the "read-only" status so that the file absolutely cannot be altered in any way? Copied is OK. Displayed is OK. Viewed is OK. But NO change to color, saturation, sharpness, etc. Is that possible? How do I do this?

I wouldn't think so. If you can open it, you can always change it and save it with a different file name.

I was afraid that was the case, but thanks for your reply - I truly appreciate it!