(Swift) Check Internet Connectivity
Demonstrates an efficient way to test for Internet connectivity.
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(targetIp, port: port, ssl: ssl, maxWaitMs: timeoutMs)
if success == false {
print("\(socket.lastErrorText!)")
return
}
socket.close(10)
print("We have Internet connectivity.")
}
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