Can't open files unless there's an extension

[OscarGodson]

This makes it sort of a pain because file uploads don't have extensions. They look something like /var/folders/fm/vyvfk53d2b5gf63m7dnv3gqc0000gn/T/33ba4e6ef6ded7f0369f587f17090af4. So, to get around this, I have to rename it to the name it was uploaded as before giving it to lwip. I believe you should be able to use something like: https://github.com/rosszurowski/mime-sniffer/ and read it based on the actual file type, not the extension of the file.

[EyalAr]

Detecting mime types is not in the scope of lwip.
It's very application-specific. Not all apps will use lwip to process images uploaded to a web server.

You could use the module you suggested to detect the type of image uploaded to your server, and thus give lwip the correct type when opening the file.

What lwip could do, is detect the image type automatically (unrelated to mime types). And indeed there's an issue for this (#87), and a PR (#96). It will be available in the next version.