Shows how to use a timer to await a print completion before checking status

ptireliancelib_ping_status.cs

using PTIRelianceLib;
using System;
using System.Drawing;
using System.Drawing.Printing;
using System.Threading;

namespace RelianceCLI
{
    internal class Program
    {
        private static int executionCount = 0;
        private static System.Timers.Timer _mTimer;
        private static AutoResetEvent _mGate;

        private static void Main(string[] args)
        {
            // Submit a print job to default printer
            PrintDocument doc = new PrintDocument();
            doc.PrintPage += (s, o) =>
            {
                // Create font and brush.
                Font drawFont;
                drawFont = new Font("Bitstream Vera Sans Mono", 29);
                SolidBrush drawBrush = new SolidBrush(Color.Black);
                o.Graphics.DrawString("Test Page", drawFont, drawBrush, 0.0F, 80.0F);

                // Long graphic to simulate long ticket
                o.Graphics.DrawEllipse(new Pen(drawBrush), new Rectangle(100, 0, 80, 1600));
            };
            doc.Print();

            // Barrier to prevent closing while timer is still waiting
            _mGate = new AutoResetEvent(false);

            _mTimer = new System.Timers.Timer(200)
            {
                AutoReset = true,
                Enabled = true,
            };
            _mTimer.Elapsed += Timer_Elapsed;

            // Wait until Ping() starts failing
            BlockUntilBusy();

            _mTimer.Start();

            _mGate.WaitOne();

            Console.ReadKey();
        }

        private static void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            using (var printer = new ReliancePrinter())
            {
                while(!printer.IsDeviceReady)
                {
                    /* Try a number of times or for period of time */
                }

                if (printer.Ping() == ReturnCodes.Okay)
                {
                    var status = printer.GetStatus();
                    Console.WriteLine(status);

                    // Shutdown timer
                    _mTimer.Stop();

                    // Allow app to exit
                    _mGate.Set();
                }
                else
                {
                    Console.WriteLine("Printer is busy");
                }
            }
        }

        private static void BlockUntilBusy()
        {
            using (var printer = new ReliancePrinter())
            {
                while(!printer.DeviceReady)
                {
                    /* Try a number of times or for period of time */
                }

                while (printer.Ping() == ReturnCodes.Okay)
                {
                    /* Burn up that CPU */
                }
            }
        }
    }
}

Ideally you don't really want to burn up that CPU but this is just demonstrating worst case.