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Swift

Check Internet Connectivity

See more Socket/SSL/TLS Examples

Demonstrates an efficient way to test for Internet connectivity.

Chilkat Swift Downloads

Swift

func chilkatTest() {
    var success: Bool = false

    let socket = CkoSocket()!
    // 1. Use a reliable Anycast IP. 
    //    8.8.8.8 (Google) or 1.1.1.1 (Cloudflare) are the industry standards.
    var targetIp: String? = "8.8.8.8"

    // 2. Use Port 53 (DNS). 
    //    DNS servers typically listen on TCP Port 53 as well as UDP. 
    //    (Alternatively, use port 443 if you suspect port 53 is blocked).
    var port: Int = 53

    // 3. Disable SSL (0). 
    //    We are not doing a handshake, just a TCP connection.
    var ssl: Bool = false

    // 4. Short Timeout (1500ms).
    //    If you can't reach Google in 1.5 seconds, the connection is 
    //    likely too poor for practical use anyway.
    var timeoutMs: Int = 1500

    // Connect
    success = socket.connect(hostname: targetIp, port: port, ssl: ssl, maxWaitMs: timeoutMs)
    if success == false {
        print("\(socket.lastErrorText!)")
        return
    }

    socket.close(maxWaitMs: 10)

    print("We have Internet connectivity.")

}