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Swift

Check Whether a Socket Is Writable

See more Socket/SSL/TLS Examples

Demonstrates Socket.CheckWriteable, which waits for the connected socket to become writable. It returns 1 if writable, 0 if it did not become writable before the timeout, or -1 on error.

Background. A maxWaitMs of 0 performs a nonblocking poll. This is useful for flow control before attempting a large send.

Chilkat Swift Downloads

Swift

func chilkatTest() {
    var success: Bool = false

    let socket = CkoSocket()!

    //  Connect to the server using TLS.
    var bTls: Bool = true
    var maxWaitMs: Int = 5000
    success = socket.connect(hostname: "example.com", port: 5000, ssl: bTls, maxWaitMs: maxWaitMs)
    if success == false {
        print("\(socket.lastErrorText!)")
        return
    }

    //  Wait up to 5 seconds for the socket to become writable.  Returns 1 if writable, 0 if it did not
    //  become writable before the timeout, or -1 on error.
    var writable: Int = socket.checkWriteable(maxWaitMs: 5000).intValue
    if writable < 0 {
        print("\(socket.lastErrorText!)")
        return
    }

    if writable != 1 {
        print("The socket did not become writable before the timeout.")
        return
    }

    print("The socket is writable.")

}