HaishinKit.swift/RTCHaishinKit/Sources/RTC/RTCChannel.swift

import Foundation
import HaishinKit
import libdatachannel

protocol RTCChannel {
    var id: Int32 { get }

    func send(_ message: Data) throws
}

extension RTCChannel {
    public func send(_ message: Data) throws {
        try RTCError.check(message.withUnsafeBytes { pointer in
            return rtcSendMessage(id, pointer.bindMemory(to: CChar.self).baseAddress, Int32(message.count))
        })
    }
}