The Winamp Collaborative License is a free, copyleft license for software and other kinds of works. It is designed to ensure that you have the freedom to use, Modify, and study the software, but with certain restrictions on the distribution of modifications to maintain the integrity and collaboration of the project.
Oh god....
No Distribution of Modified Versions: You may not distribute modified versions of the software, whether in source or binary form.
No Forking: You may not create, maintain, or distribute a forked version of the software.
Official Distribution: Only the maintainers of the official repository are allowed to distribute the software and its modifications.
Copy left is not a protected term but yeah this is a shit license.
And how the fuck do you contribute code back without forking the project?!
EDIT: It looks like an issue has already been created and I absolutely love this thread where the license they are using is in violation of Github TOS.
They should have just kept the source closed! The speculation is that whomever purchased it wants to crowdsource contributions without adding any value themselves.
People on Hacker News are speculating that they implicitly define forking as "taking the project in a different direction in an independent repo". The Github TOS say that everyone has the right to create a fork of any public repo in the Github sense of the word. It's all a huge mess...
The community has been making Winamp clones for as long as Winamp has existed. XMMS appeared the same year as Winamp, in 1997. Audacious is still around and still has a mode where it uses Winamp skins.
The thing about Winamp is that it had its time in the spotlight for a few years and then everybody moved on to the new types of media libraries like foobar2000. Today it's just a museum piece.
I'm curious, why does this require OpenSSL in order to compile? I'm not aware of any audio formats that use encryption, but I could be wrong.
My first thought was for connecting to https streams, but I don't remember Winamp having this capability. "Back in the day," I used Winamp for playing local audio and RealPlayer for what little streaming was available.
Three streaming (like pointed in the other comment) was my initial reaction too, but indeed at the time https for streaming would be very rare.
Another possibility is to realize that openssl isn't just for communication, but also has implementation of cryptographic algorithms.
Perhaps openssl was used for validation of licensing key? For example they could sign the license with their private key and WinAmp could verify it's authenticity with its public key.