kCFStreamErrorSOCKSUnknownClientVersion

The SOCKS server rejected access because it does not support connections with the requested SOCKS version. SOCKS client version. You can query the kCFSOCKSVersionKey key to find out what version the server requested. This error code is only valid for errors in the kCFStreamErrorSOCKSSubDomainNone subdomain.

var kCFStreamErrorSOCKSUnknownClientVersion: Int { get }