How do I create my own URL protocol? (e.g. so://…)

Question

I have seen:

• http://www...
• ftp://blah.blah...
• file://blah.blah...
• unreal://blah.blah...
• mailto://blah.blah...

What is that first section where you see http and the like called?

Can I register my own?

Answer 1

It's called the protocol. The only thing that prevents you from making your own protocol is you have to:

1. Write a browser or user agent of some kinds that understands that protocol, both in its URL form and in the actual data format
2. Write a server that understands that protocol
3. Preferably, have a specification for the protocol so that browser and server can continue to work together.

Windows makes #1 really easy, an in many cases this is all you actually need. Viz:

Registering an Application to a URL Protocol

Answer 2

For most Microsoft products (Internet Explorer, Office, "open file" dialogs etc) you can register an application to be run when URI with appropriate prefix is opened. This is a part of more common explanation - how to implement your own protocol.

For Mozilla the explanation is here, Java - here.

Answer 3

A Protocol?

I found this, it appears to be a local setting for a computer...

http://kb.mozillazine.org/Register_protocol

Answer 4

Here's a list of the registered URI schemes. Each one has an RFC - a document defining it, which is almost a standard. The RFC tells the developers of new applications (such as browsers, ftp clients, etc.) what they need to support. If you need a new base-level protocol, you can use an unregistered one. The other answers tell you how. Please keep in mind you can do lots of things with the existing protocols, thus gaining their existing implementations.

Answer 5

You don't really have to do any registering as such. I've seen many programs, like emule, create their own protocol specificier (that's what I think it's called). After that, you basically just have to set some values in the registry as to what program handles that protocol. I'm not sure if there's any official registry of protocol specifiers. There isn't really much to stop you from creating your own protocol specifier for your own application if you want people to open your app from their browser.

Answer 6

The portion with the HTTP://,FTP://, etc are called URI Schemes

You can register your own through the registry.

HKEY_CLASSES_ROOT/
  your-protocol-name/
    (Default)    "URL:your-protocol-name Protocol"
    URL Protocol ""
    shell/
      open/
        command/
          (Default) PathToExecutable

Sources: https://www.iana.org/assignments/uri-schemes/uri-schemes.xhtml, http://msdn.microsoft.com/en-us/library/aa767914(v=vs.85).aspx