virusscan a stream before storing on disk

Question

I've found a lot of solutions of how to scan uploaded files. My issue is this: Every single solution on internet starts scanning after a stream is saved as a file.

My Question: Can a file harm the server at the moment its stored at the disk? If so, is it possible to viruscheck an uploaded stream before storing it on the harddrive?

Answer 1

A file is just a series of bytes. The OS isn't going to run that file when you save it to disk. Saving it to disk won't harm you, but make sure you remove that file when you detect a virus.

I don't think you can easily verify a stream, since virus scanners are most often processes that deal with files.