How can i get the ID of a new created message?

I want to create a message and attach a file to this new message by using the API. I can only attach the file to the message if i know the ID of the Message. SO how i can get this ID?

When you post a new message via the Unfuddle API, a successful response will also contain a header “Location” which contains the canonical URL for the created message. The last digit in this URL is the ID of the newly created message.

For instance:

Location: https://subdomain.unfuddle.com/api/v1/projects/4/messages/123.xml

In this case, “123” is the id of the new message.