We've a form that requires an upload for members to submit paperwork; usually a PDF, sometimes a graphics file. They're customers, so what they call it and send it as is unpredictable.
Our site is on a VPS, so I'm not sure where I'd add a hook for this. I want to strip out any weird characters. The uploaded file becomes a link for our associates, so it can't have any goofy characters in it. Or, instead of just stripping them, it could replace them with the right HTML code ( # becomes %23, spaces to %20, etc.). What's the best way of doing this?