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Missing Output when Redirecting Standard Error in C# / .NET Process

I'm working with a 3rd party, command-line tool called "sam-ba" v3.5 (available here for free). It's a C++ / QML command line tool that interfaces with a hardware module to read/write data. Output from commands, in most cases, is sent to Standard Error.
I have a C# / .NET application that creates a Process object to execute the sam-ba tool and run commands. Executing the commands works as expected. What doesn't always work is the redirect of the Standard Error output. In some commands, part or all of the output is not received by the C# application. For example, here is the execution of a command using the sam-ba tool directly at the Windows 10 command line:
C:\Temp\Stuff\sam-ba_3.5>sam-ba -p serial:COM5 -d sama5d3 -m version
Error: Cannot open invalid port 'COM5'
Cannot open invalid port 'COM5'
Here is some simple code from a C# application to create a Process object to execute the sam-ba tool with the same command:
Process p = new Process
{
StartInfo = new ProcessStartInfo("sam-ba.exe", "-p serial:COM5 -d sama5d3 -m version")
{
RedirectStandardOutput = true,
RedirectStandardError = true,
UseShellExecute = false,
CreateNoWindow = true
}
};
p.Start();
string output = p.StandardOutput.ReadToEnd();
string error = p.StandardError.ReadToEnd();
p.WaitForExit();
Console.WriteLine("Standard Out: " + output);
Console.WriteLine("Standard Error: " + error);
The Output of the C# application:
Standard Out:
Standard Error: Cannot open invalid port 'COM5'
In this simple example, only 1 of the output lines is redirected to Standard Error while the other is not. I've tried many different commands and results are mixed. Sometimes I get everything, sometimes partial output, sometimes no output.
Now ... here's the real issue. The following is a python script (v3.8) that does exactly what the C# application is doing:
import subprocess
import sys
result = subprocess.run("sam-ba.exe -p serial:COM5 -d sama5d3 -m version", capture_output=True, text=True)
print("stdout:", result.stdout)
print("stderr:", result.stderr)
This script always returns the correct output to standard error. BUT ... when I run this script from the C# app to create a chain of C# -> python -> sam-ba, I get the same issue of output missing from the stream.
This has led me to 2 conclusions:
Something in that sam-ba tool is different about the way it is outputting its text. Format, content, ... something. There's an inconsistency going on somewhere in that code
Something is different about the environment created by the C# Process object when executing external applications that doesn't happen when the external application is run directly. Otherwise, why would the python script get all the output when run directly, but not when run through the C# Process object?
It is #2 that has brought me here. I'm looking for any insight on how to diagnose this. Something I'm doing wrong, settings I can try within the Process object, thoughts on how data can go into a stream and not come out on redirect, or if anyone has ever seen something like this before and how they resolved it.
UPDATE
Got a hold of the sam-ba tool's source code. The output the C# app is not capturing is coming from the QML files. They are using this 'print()' method that I can't really find any details on. The output the C# app can capture is being delivered back to the C++ side via signals and then sent to standard error. This feeds back into my conclusion #1 where they have inconsistencies in their code.
Still, this potentially means there is a conflict between C# and QT/QML, which would explain why the Python script gets the QML output, but the C# app does not.

The following uses ShellExecute instead of CreateProcess when running
process. When using ShellExecute one can't re-direct StandardOutput and/or StandardError for Process. To work around this, both StandardOutput and StandardError are re-directed to a temp file, and then the data is read from the temp file--which seems to result in the same output that one sees when running from a cmd window.
Note: In the following code it's necessary to use %windir%\system32\cmd.exe (ex: C:\Windows\system32\cmd.exe) with the /c option. See the usage section below.
Add using statement: using System.Diagnostics;
Then try the following:
public string RunProcess(string fqExePath, string arguments, bool runAsAdministrator = false)
{
string result = string.Empty;
string tempFilename = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "tempSam-ba.txt");
string tempArguments = arguments;
if (String.IsNullOrEmpty(fqExePath))
{
Debug.WriteLine("fqExePath not specified");
return "Error: fqExePath not specified";
}
//redirect both StandardOutput and StandardError to a temp file
if (!arguments.Contains("2>&1"))
{
tempArguments += String.Format(" {0} {1} {2}", #"1>", tempFilename, #"2>&1");
}
//create new instance
ProcessStartInfo startInfo = new ProcessStartInfo(fqExePath, tempArguments);
if (runAsAdministrator)
{
startInfo.Verb = "runas"; //elevates permissions
}//if
//set environment variables
//pStartInfo.EnvironmentVariables["SomeVar"] = "someValue";
startInfo.RedirectStandardError = false;
startInfo.RedirectStandardOutput = false;
startInfo.RedirectStandardInput = false;
startInfo.UseShellExecute = true; //use ShellExecute instead of CreateProcess
startInfo.CreateNoWindow = false;
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.ErrorDialog = false;
startInfo.WorkingDirectory = System.IO.Path.GetDirectoryName(fqExePath);
using (Process p = Process.Start(startInfo))
{
//start
p.Start();
//waits until the process is finished before continuing
p.WaitForExit();
}
//read output from temp file
//file may still be in use, so try to read it.
//if it is still in use, sleep and try again
if (System.IO.File.Exists(tempFilename))
{
string errMsg = string.Empty;
int count = 0;
do
{
//re-initialize
errMsg = string.Empty;
try
{
result = System.IO.File.ReadAllText(tempFilename);
Debug.WriteLine(result);
}
catch(System.IO.IOException ex)
{
errMsg = ex.Message;
}
catch (Exception ex)
{
errMsg = ex.Message;
}
System.Threading.Thread.Sleep(125);
count += 1; //increment
} while (!String.IsNullOrEmpty(errMsg) && count < 10);
//delete temp file
System.IO.File.Delete(tempFilename);
}
return result;
}
Usage:
RunProcess(#"C:\Windows\system32\cmd.exe", #"/c C:\Temp\sam-ba_3.5\sam-ba.exe -p serial:COM5 -d sama5d3 -m version");
Note: /c C:\Temp\sam-ba_3.5\sam-ba.exe -p serial:COM5 -d sama5d3 -m version is the value of the process "Argument" property.
Update:
Option 2:
Here's a solution that uses named pipes. Process is used to redirect the output to a named pipe instead of a file. One creates a named pipe "server" which listens for a connection from a client.Then System.Diagnostics.Process is used to run the desired command and redirect the output to the named pipe server. The "server" reads the output, and then raises event "DataReceived" which will return the data to any subscribers.
The named pipe server code is from here, however I've modified it. I've added numerous events--which can be subscribed to. I've also added the ability for the server to shut itself down after it's finished reading the data by setting "ShutdownWhenOperationComplete" to "true".
Create a class named: HelperNamedPipeServer.cs
HelperNamedPipeServer.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO.Pipes;
using System.IO;
using System.Diagnostics;
using System.Threading;
using System.Security.Principal;
namespace ProcessTest
{
public class HelperNamedPipeServer : IDisposable
{
//delegates
public delegate void EventHandlerClientConnected(object sender, bool e);
public delegate void EventHandlerDataReceived(object sender, string data);
public delegate void EventHandlerOperationCompleted(object sender, bool e);
public delegate void EventHandlerMessageComplete(object sender, bool e);
public delegate void EventHandlerReadComplete(object sender, bool e);
public delegate void EventHandlerServerShutdown(object sender, bool e);
public delegate void EventHandlerServerStarted(object sender, bool e);
//event that subscribers can subscribe to
public event EventHandlerClientConnected ClientConnected;
public event EventHandlerDataReceived DataReceived;
public event EventHandlerMessageComplete MessageReadComplete;
public event EventHandlerOperationCompleted OperationCompleted;
public event EventHandlerReadComplete ReadComplete;
public event EventHandlerServerShutdown ServerShutdown;
public event EventHandlerServerStarted ServerStarted;
public bool IsClientConnected
{
get
{
if (_pipeServer == null)
{
return false;
}
else
{
return _pipeServer.IsConnected;
}
}
}
public string PipeName { get; set; } = string.Empty;
public bool ShutdownWhenOperationComplete { get; set; } = false;
//private int _bufferSize = 4096;
private int _bufferSize = 65535;
//private volatile NamedPipeServerStream _pipeServer = null;
private NamedPipeServerStream _pipeServer = null;
public HelperNamedPipeServer()
{
PipeName = "sam-ba-pipe";
}
public HelperNamedPipeServer(string pipeName)
{
PipeName = pipeName;
}
private NamedPipeServerStream CreateNamedPipeServerStream(string pipeName)
{
//named pipe with security
//SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.BuiltinAdministratorsSid, null); //member of Administrators group
//SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.WorldSid, null); //everyone
//SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.BuiltinUsersSid, null); //member of Users group
//PipeAccessRule rule = new PipeAccessRule(sid, PipeAccessRights.ReadWrite, System.Security.AccessControl.AccessControlType.Allow);
//PipeSecurity pSec = new PipeSecurity();
//pSec.AddAccessRule(rule);
//named pipe - with specified security
//return new NamedPipeServerStream(PipeName, PipeDirection.InOut, NamedPipeServerStream.MaxAllowedServerInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous, _bufferSize, _bufferSize, pSec);
//named pipe - access for everyone
//return new System.IO.Pipes.NamedPipeServerStream(pipeName, PipeDirection.InOut, NamedPipeServerStream.MaxAllowedServerInstances, PipeTransmissionMode.Message, PipeOptions.Asynchronous);
return new System.IO.Pipes.NamedPipeServerStream(pipeName, PipeDirection.InOut, NamedPipeServerStream.MaxAllowedServerInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
}
public void Dispose()
{
Shutdown();
}
private void OnClientConnected()
{
LogMsg("OnClientConnected");
//raise event
if (ClientConnected != null)
ClientConnected(this, true);
}
private void OnDataReceived(string data)
{
LogMsg("OnClientConnected");
//raise event
if (DataReceived != null && !String.IsNullOrEmpty(data))
{
if (DataReceived != null)
DataReceived(this, data);
}
}
private void OnMessageReadComplete()
{
LogMsg("OnMessageReadComplete");
//raise event
if (MessageReadComplete != null)
MessageReadComplete(this, true);
}
private void OnOperationCompleted()
{
LogMsg("OnOperationCompleted");
//raise event
if (OperationCompleted != null)
OperationCompleted(this, true);
}
private void OnReadComplete()
{
LogMsg("OnReadComplete");
//raise event
if (ReadComplete != null)
ReadComplete(this, true);
}
private void OnServerShutdown()
{
LogMsg("OnServerShutdown");
//raise event
if (ServerShutdown != null)
ServerShutdown(this, true);
}
private void OnServerStarted()
{
LogMsg("OnServerStarted");
//raise event
if (ServerStarted != null)
ServerStarted(this, true);
}
private async void DoConnectionLoop(IAsyncResult result)
{ //wait for connection, then process the data
if (!result.IsCompleted) return;
if (_pipeServer == null) return;
//IOException = pipe is broken
//ObjectDisposedException = cannot access closed pipe
//OperationCanceledException - read was canceled
//accept client connection
try
{
//client connected - stop waiting for connection
_pipeServer.EndWaitForConnection(result);
OnClientConnected(); //raise event
}
catch (IOException) { RebuildNamedPipe(); return; }
catch (ObjectDisposedException) { RebuildNamedPipe(); return; }
catch (OperationCanceledException) { RebuildNamedPipe(); return; }
while (IsClientConnected)
{
if (_pipeServer == null) break;
try
{
// read from client
string clientMessage = await ReadClientMessageAsync(_pipeServer);
OnDataReceived(clientMessage); //raise event
}
catch (IOException) { RebuildNamedPipe(); return; }
catch (ObjectDisposedException) { RebuildNamedPipe(); return; }
catch (OperationCanceledException) { RebuildNamedPipe(); return; }
}
//raise event
OnOperationCompleted();
if (!ShutdownWhenOperationComplete)
{
//client disconnected. start listening for clients again
if (_pipeServer != null)
RebuildNamedPipe();
}
else
{
Shutdown();
}
}
private void LogMsg(string msg)
{
//ToDo: log message
string output = String.Format("{0} - {1}", DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss"), msg);
//ToDo: uncomment this line, if desired
//Debug.WriteLine(output);
}
private void RebuildNamedPipe()
{
Shutdown();
_pipeServer = CreateNamedPipeServerStream(PipeName);
_pipeServer.BeginWaitForConnection(DoConnectionLoop, null);
}
private async Task<string> ReadClientMessageAsync(NamedPipeServerStream stream)
{
byte[] buffer = null;
string clientMsg = string.Empty;
StringBuilder sb = new StringBuilder();
int msgIndex = 0;
int read = 0;
LogMsg("Reading message...");
if (stream.ReadMode == PipeTransmissionMode.Byte)
{
LogMsg("PipeTransmissionMode.Byte");
//byte mode ignores message boundaries
do
{
//create instance
buffer = new byte[_bufferSize];
read = await stream.ReadAsync(buffer, 0, buffer.Length);
if (read > 0)
{
clientMsg = Encoding.UTF8.GetString(buffer, 0, read);
//string clientMsg = Encoding.Default.GetString(buffer, 0, read);
//remove newline
//clientMsg = System.Text.RegularExpressions.Regex.Replace(clientString, #"\r\n|\t|\n|\r|", "");
//LogMsg("clientMsg [" + msgIndex + "]: " + clientMsg);
sb.Append(clientMsg);
msgIndex += 1; //increment
}
} while (read > 0);
//raise event
OnReadComplete();
OnMessageReadComplete();
}
else if (stream.ReadMode == PipeTransmissionMode.Message)
{
LogMsg("PipeTransmissionMode.Message");
do
{
do
{
//create instance
buffer = new byte[_bufferSize];
read = await stream.ReadAsync(buffer, 0, buffer.Length);
if (read > 0)
{
clientMsg = Encoding.UTF8.GetString(buffer, 0, read);
//string clientMsg = Encoding.Default.GetString(buffer, 0, read);
//remove newline
//clientMsg = System.Text.RegularExpressions.Regex.Replace(clientString, #"\r\n|\t|\n|\r|", "");
//LogMsg("clientMsg [" + msgIndex + "]: " + clientMsg);
sb.Append(clientMsg);
msgIndex += 1; //increment
}
} while (!stream.IsMessageComplete);
//raise event
OnMessageReadComplete();
} while (read > 0);
//raise event
OnReadComplete();
LogMsg("message completed");
}
return sb.ToString();
}
private void Shutdown()
{
LogMsg("Shutting down named pipe server");
if (_pipeServer != null)
{
try { _pipeServer.Close(); } catch { }
try { _pipeServer.Dispose(); } catch { }
_pipeServer = null;
}
}
public void StartServer(object obj = null)
{
LogMsg("Info: Starting named pipe server...");
_pipeServer = CreateNamedPipeServerStream(PipeName);
_pipeServer.BeginWaitForConnection(DoConnectionLoop, null);
}
public void StopServer()
{
Shutdown();
OnServerShutdown(); //raise event
LogMsg("Info: Server shutdown.");
}
}
}
Next, I've created a "Helper" class that contains the code to start the named pipe server, run the command using Process, and return the data. There are three ways to get the data. It's returned by the method, one can subscribe to the "DataReceived" event, or once the method completes, the data will be in property "Data".
Helper.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.IO.Pipes;
using System.IO;
using System.Threading;
namespace ProcessTest
{
public class Helper : IDisposable
{
public delegate void EventHandlerDataReceived(object sender, string data);
//event that subscribers can subscribe to
public event EventHandlerDataReceived DataReceived;
private StringBuilder _sbData = new StringBuilder();
private HelperNamedPipeServer _helperNamedPipeServer = null;
private bool _namedPipeServerOperationComplete = false;
public string Data { get; private set; } = string.Empty;
public Helper()
{
}
private void OnDataReceived(string data)
{
if (!String.IsNullOrEmpty(data) && DataReceived != null)
{
DataReceived(this, data);
//Debug.Write("Data: " + data);
}
}
public void Dispose()
{
ShutdownNamedPipeServer();
}
public async Task<string> RunSambaNamedPipesAsync(string fqExePath, string arguments, string pipeName = "sam-ba-pipe", string serverName = ".", bool runAsAdministrator = false)
{
string result = string.Empty;
string tempArguments = arguments;
//re-initialize
_namedPipeServerOperationComplete = false;
_sbData = new StringBuilder();
Data = string.Empty;
if (String.IsNullOrEmpty(fqExePath))
{
Debug.WriteLine("fqExePath not specified");
return "fqExePath not specified";
}
//create new instance
_helperNamedPipeServer = new HelperNamedPipeServer(pipeName);
_helperNamedPipeServer.ShutdownWhenOperationComplete = true;
//subscribe to events
_helperNamedPipeServer.DataReceived += HelperNamedPipeServer_DataReceived;
_helperNamedPipeServer.OperationCompleted += HelperNamedPipeServer_OperationCompleted;
//start named pipe server on it's own thread
Thread t = new Thread(_helperNamedPipeServer.StartServer);
t.Start();
//get pipe name to use with Process
//this is where output from the process
//will be redirected to
string fqNamedPipe = string.Empty;
if (String.IsNullOrEmpty(serverName))
{
fqNamedPipe = String.Format(#"\\{0}\pipe\{1}", serverName, pipeName);
}
else
{
fqNamedPipe = String.Format(#"\\{0}\pipe\{1}", ".", pipeName);
}
//redirect both StandardOutput and StandardError to named pipe
if (!arguments.Contains("2>&1"))
{
tempArguments += String.Format(" {0} {1} {2}", #"1>", fqNamedPipe, #"2>&1");
}
//run Process
RunProcess(fqExePath, tempArguments, runAsAdministrator);
while (!_namedPipeServerOperationComplete)
{
await Task.Delay(125);
}
//set value
Data = _sbData.ToString();
return Data;
}
public void RunProcess(string fqExePath, string arguments, bool runAsAdministrator = false)
{
if (String.IsNullOrEmpty(fqExePath))
{
Debug.WriteLine("fqExePath not specified");
throw new Exception( "Error: fqExePath not specified");
}
//create new instance
ProcessStartInfo startInfo = new ProcessStartInfo(fqExePath, arguments);
if (runAsAdministrator)
{
startInfo.Verb = "runas"; //elevates permissions
}//if
//set environment variables
//pStartInfo.EnvironmentVariables["SomeVar"] = "someValue";
startInfo.RedirectStandardError = false;
startInfo.RedirectStandardOutput = false;
startInfo.RedirectStandardInput = false;
startInfo.UseShellExecute = true; //use ShellExecute instead of CreateProcess
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.ErrorDialog = false;
startInfo.WorkingDirectory = System.IO.Path.GetDirectoryName(fqExePath);
using (Process p = Process.Start(startInfo))
{
//start
p.Start();
//waits until the process is finished before continuing
p.WaitForExit();
}
}
private void HelperNamedPipeServer_OperationCompleted(object sender, bool e)
{
//Debug.WriteLine("Info: Named pipe server - Operation completed.");
//set value
Data = _sbData.ToString();
//set value
_namedPipeServerOperationComplete = true;
}
private void HelperNamedPipeServer_DataReceived(object sender, string data)
{
Debug.WriteLine("Info: Data received from named pipe server.");
if (!String.IsNullOrEmpty(data))
{
//append
_sbData.Append(data.TrimEnd('\0'));
//send data to subscribers
OnDataReceived(data);
}
}
private void ShutdownNamedPipeServer()
{
Debug.WriteLine("Info: ShutdownNamedPipeServer");
try
{
if (_helperNamedPipeServer != null)
{
//unsubscribe from events
_helperNamedPipeServer.DataReceived -= HelperNamedPipeServer_DataReceived;
_helperNamedPipeServer.OperationCompleted -= HelperNamedPipeServer_OperationCompleted;
_helperNamedPipeServer.Dispose();
_helperNamedPipeServer = null;
}
}
catch (Exception ex)
{
}
}
}
}
Usage:
private async void btnRunUsingNamedPipes_Click(object sender, EventArgs e)
{
//Button name: btnRunUsingNamedPipes
using (Helper helper = new Helper())
{
//subscribe to event
helper.DataReceived += Helper_DataReceived;
var result = await helper.RunSambaNamedPipesAsync(#"C:\Windows\system32\cmd.exe", #"/c C:\Temp\sam-ba_3.5\sam-ba.exe -p serial:COM5 -d sama5d3 -m version");
Debug.WriteLine("Result: " + result);
//unsubscribe from event
helper.DataReceived -= Helper_DataReceived;
}
}
private void Helper_DataReceived(object sender, string data)
{
//System.Diagnostics.Debug.WriteLine(data);
//RichTextBox name: richTextBoxOutput
if (richTextBoxOutput.InvokeRequired)
{
richTextBoxOutput.Invoke((MethodInvoker)delegate
{
richTextBoxOutput.Text = data;
richTextBoxOutput.Refresh();
});
}
}
Resources:
When do we need to set ProcessStartInfo.UseShellExecute to True?
Redirecting error messages from Command Prompt: STDERR/STDOUT
PipeTransmissionMode.Message: How do .NET named pipes distinguish between messages?
WellKnownSidType Enum

My Windows Service failing to get started after a reboot

I can successfully Start/Stop service Manually but it fails to start on a system restart although startup type is set to 'Automatic'. On some terminal, when rebooted, service fail to start with error failed to connect DB
29052019 17:25:27 ERROR Logs.TransactionLogManager - Exception Thrown in getNewSession()
29052019 17:25:27 ERROR Logs.TransactionLogManager - Unable To Open Database Session
29052019 17:25:27 ERROR Logs.TransactionLogManager - Unable to complete network request to host "localhost".
at FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()
at FirebirdSql.Data.FirebirdClient.FbConnectionPoolManager.Pool.CreateNewConnectionIfPossibleImpl(FbConnectionString connectionString)
at FirebirdSql.Data.FirebirdClient.FbConnectionPoolManager.Pool.GetConnection(FbConnection owner)
at FirebirdSql.Data.FirebirdClient.FbConnection.Open()
at NHibernate.Connection.DriverConnectionProvider.GetConnection()
at NHibernate.Tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.Prepare()
at NHibernate.Tool.hbm2ddl.SchemaMetadataUpdater.GetReservedWords(Dialect dialect, IConnectionHelper connectionHelper)
at NHibernate.Tool.hbm2ddl.SchemaMetadataUpdater.Update(ISessionFactory sessionFactory)
at NHibernate.Impl.SessionFactoryImpl..ctor(Configuration cfg, IMapping mapping, Settings settings, EventListeners listeners)
at NHibernate.Cfg.Configuration.BuildSessionFactory()
at StevensCommon.Database.FluentNHibernateManager.OpenNewSession()
at StevensCommon.DAOs.StevensDAO.GetNewSession()
On development environment whilst debugging I'm not even getting any error. Assuming that on my machine the firebird services does start up before my service, still it fails to start the service on a reboot. And nothing comes up in the log.
I've added some log points within the code and they all gets logged when I Stop/Start the service manually. But nothing shows up in the log when system is rebooted and server never gets started.
Tried adding Firebird Service as a dependencies in the Project/Service Installer, set the DelayedAutoStart = true. Whatever solution I read online I've tried it but service is not starting on a reboot.
Following I'm adding starting/entry point snippet of the service.
Program.cs
static class Program
{
static void Main(string[] args)
{
TransactionLogManager.WriteServiceLog("FLAG - Before DAO Call", null);
// Check to see if we have a licence
if (LicenceFileDAO.GetLicence() != null && LicenceManager.IsLicenceActive())
{
TransactionLogManager.WriteServiceLog("FLAG - Inside DAO Block", null);
//Run the IS Service
ServiceBase[] ServicesToRun = new ServiceBase[] { new MyService() };
ServiceBase.Run(ServicesToRun);
TransactionLogManager.WriteServiceLog("FLAG - End of DAO Call", null);
}
else
{
TransactionLogManager.WriteServiceLog("No Valid Licence Found - Either A Licence Has Not Been Activated Or It Has Expired. Please Contact Support", null);
}
}
}
MyService.cs
public partial class MyService : ServiceBase
{
protected static Timer importTimer = null;
protected static Timer exportTimer = null;
protected static Timer licenceTimer = null;
protected static Timer requestTimer = null;
protected static Timer uploadTimer = null;
protected static Timer handshakeTimer = null;
protected static Timer scheduledReportTimer = null;
protected static Timer alertTimer = null;
public static Boolean ImportRunning = false;
public static Boolean ExportRunning = false;
public static Boolean RequestRunning = false;
public static Boolean UploadRunning = false;
public static Boolean HandshakeRunning = false;
public static Boolean ScheduledReportRunning = false;
public static Boolean AlertReportRunning = false;
public static int? zynkWorkflowProcessId = null;
public MyService()
{
TransactionLogManager.WriteServiceLog("FLAG - 1", null);
InitializeComponent();
InitializeServiceTimers();
try
{
MessengerService.Start();
TransactionLogManager.WriteServiceLog("Messaging Service Started", null);
}
catch (Exception e)
{
TransactionLogManager.WriteServiceLog(e.Message, e.StackTrace);
}
}
private void InitializeComponent()
{
this.eventLog1 = new System.Diagnostics.EventLog();
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).BeginInit();
//
// MyService
//
this.ServiceName = "MyService";
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).EndInit();
}
private void InitializeServiceTimers()
{
if (!System.Diagnostics.EventLog.SourceExists("Stevens Integration Service"))
{
System.Diagnostics.EventLog.CreateEventSource(
"Stevens Integration Service", "ServiceLog");
}
eventLog1.Source = "Stevens Integration Service";
eventLog1.Log = "ServiceLog";
TransactionLogManager.WriteServiceLog("FLAG - 2", null);
importTimer = new Timer(IntegrationServiceSettings.GetImportInterval() * 1000);
exportTimer = new Timer(IntegrationServiceSettings.GetExportInterval() * 1000);
licenceTimer = new Timer(86400 * 1000); // Daily
requestTimer = new Timer(IntegrationServiceSettings.GetRequestInterval() * 1000);
scheduledReportTimer = new Timer(30000);
alertTimer = new Timer(20000);
importTimer.Elapsed += new ElapsedEventHandler(ImportTimerElapsed);
exportTimer.Elapsed += new ElapsedEventHandler(ExportTimerElapsed);
licenceTimer.Elapsed += new ElapsedEventHandler(LicenceTimerElapsed);
requestTimer.Elapsed += new ElapsedEventHandler(RequestTimerElapsed);
scheduledReportTimer.Elapsed += new ElapsedEventHandler(ScheduledReportTimerElapsed);
alertTimer.Elapsed += new ElapsedEventHandler(AlertTimerElapsed);
TransactionLogManager.WriteServiceLog("FLAG - 3", null);
StartTimers();
TransactionLogManager.WriteServiceLog("FLAG - 4", null);
}
protected override void OnStart(string[] args)
{
eventLog1.WriteEntry("Stevens Integration Service Starting...");
TransactionLogManager.WriteServiceLog("FLAG - OnStart() Started", null);
if (StevensDAO.TestConnection())
{
eventLog1.WriteEntry("Configure Settings...");
IntegrationServiceSettings.InitialiseAll();
eventLog1.WriteEntry("Done.");
}
TransactionLogManager.WriteServiceLog("FLAG - OnStart() Finished", null);
TransactionLogManager.WriteServiceLogInfo("Started");
eventLog1.WriteEntry("Started.");
}
}
ProjectInstaller - That Includes System.ServiceProcess.ServiceProcessInstaller and System.ServiceProcess.ServiceInstaller
private System.ServiceProcess.ServiceProcessInstaller serviceProcessInstaller1;
private System.ServiceProcess.ServiceInstaller serviceInstaller1;
private MyService myService ;
private void InitializeComponent()
{
this.serviceProcessInstaller1 = new System.ServiceProcess.ServiceProcessInstaller();
this.serviceInstaller1 = new System.ServiceProcess.ServiceInstaller();
this.myService = new IntegrationService.MyService();
// serviceProcessInstaller1
this.serviceProcessInstaller1.Account = System.ServiceProcess.ServiceAccount.LocalSystem;
this.serviceProcessInstaller1.Password = null;
this.serviceProcessInstaller1.Username = null;
// serviceInstaller1
this.serviceInstaller1.Description = "My Integration Service";
this.serviceInstaller1.DisplayName = "MyService";
this.serviceInstaller1.ServiceName = "MyService";
//this.serviceInstaller1.ServicesDependedOn = new string[] { "Firebird Guardian - DefaultInstance", "Firebird Server - DefaultInstance" };
//this.serviceInstaller1.DelayedAutoStart = true;
this.serviceInstaller1.StartType = System.ServiceProcess.ServiceStartMode.Automatic;
// myService
this.myService.ExitCode = 0;
this.myService.ServiceName = "MyService";
// ProjectInstaller
this.Installers.AddRange(new System.Configuration.Install.Installer[] {
this.serviceProcessInstaller1,
this.serviceInstaller1});
}
LogPoints - On manual Start/Stop I do get following log points, but when I reboot the system nothing comes up
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - Before DAO Call
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - Inside DAO Block
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - 1
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - 2
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - 3
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - 4
30052019 16:19:35 ERROR Logs.TransactionLogManager - Messaging Service Started
30052019 16:19:35 ERROR Logs.TransactionLogManager - FLAG - OnStart() Started
30052019 16:19:35 ERROR Logs.TransactionLogManager - Client 1 is now connected!
30052019 16:19:36 ERROR Logs.TransactionLogManager - FLAG - OnStart() Finished

How to pass data from one WPF application to another WPF application?

I have two application which is Cashier.exe and Payment.exe
I want to pass the data for PosWindows.retrieveOrder from Cashier.exe to Payment.exe
PosWindows.retrieveOrder contains lots of data such as OrderId, OrderCode and more (which means its not single data)
I'm using this code but it does not send the data. is it because it cannot send a whole data like that ?
ProcessStartInfo psi = new ProcessStartInfo();
psi.FileName = "C:/Project/Application/Payment/Payment.exe";
psi.Arguments = "\"" + PosWindows.totalAmount.ToString() + "\"\"" + PosWindows.retrieveOrder + "\"";
var p = Process.Start(psi);
If I only send PosWindows.totalAmount.ToString().
which is something like this
ProcessStartInfo psi = new ProcessStartInfo();
psi.FileName = "C:/Project/Application/Payment/Payment.exe";
psi.Arguments = "\""+ PosWindows.totalAmount.ToString() + "\"";
var p = Process.Start(psi);
its working fine. but when I add PosWindows.retrieveOrder its not working.
does it impossible to send the PosWindows.retrieveOrder ?
I don't know if this problem come from this code below (because I don't declare for retrieveOrder)
This one at Payment.exe
private void app_Startup(object sender, StartupEventArgs e)
{
var args = e.Args;
if (args != null && args.Count() > 0)
{
foreach (var arg in args)
{
PaymentView.globalTotalAmount = decimal.Parse(arg);
}
}
}
if yes what will I do ? I means what should I put to replace this part decimal.Parse(arg) for retrieveOrder ?

You can use NamedPipeServerStream class.
https://learn.microsoft.com/en-us/dotnet/api/system.io.pipes.namedpipeserverstream?view=netframework-4.7.2
Take one of your apps as client, and the other as server. You can handle an async communication and parse your message when listening is completed.
Also you can check out Example of Named Pipes
Edit for solution example:
At client app, lets call the class PipeClient.cs
public void Send(string SendStr, string PipeName, int TimeOut = 1000)
{
try
{
NamedPipeClientStream pipeStream = new NamedPipeClientStream(".", PipeName, PipeDirection.Out, PipeOptions.Asynchronous);
// The connect function will indefinitely wait for the pipe to become available
// If that is not acceptable specify a maximum waiting time (in ms)
pipeStream.Connect(TimeOut);
Debug.WriteLine("[Client] Pipe connection established");
byte[] _buffer = Encoding.UTF8.GetBytes(SendStr);
pipeStream.BeginWrite(_buffer, 0, _buffer.Length, AsyncSend, pipeStream);
}
catch (Exception ex)
{
Debug.WriteLine("Pipe Send Exception: " + ex);
}
}
private void AsyncSend(IAsyncResult iar)
{
try
{
// Get the pipe
NamedPipeClientStream pipeStream = (NamedPipeClientStream)iar.AsyncState;
// End the write
pipeStream.EndWrite(iar);
pipeStream.Flush();
pipeStream.Close();
pipeStream.Dispose();
}
catch (Exception oEX)
{
Debug.WriteLine(oEX.Message);
}
}
And after you initialize your class just send the message with:
_pipeClient.Send(pipeMsg, "PipeName", Timeout);
At server app, lets call the class PipeServer.cs
public void Listen(string PipeName)
{
try
{
// Set to class level var so we can re-use in the async callback method
_pipeName = PipeName;
// Create the new async pipe
NamedPipeServerStream pipeServer = new NamedPipeServerStream(PipeName, PipeDirection.In, 1, PipeTransmissionMode.Message, PipeOptions.Asynchronous);
// Wait for a connection
pipeServer.BeginWaitForConnection(new AsyncCallback(WaitForConnectionCallBack), pipeServer);
}
catch (Exception oEX)
{
Debug.WriteLine(oEX.Message);
}
}
private void WaitForConnectionCallBack(IAsyncResult iar)
{
NamedPipeServerStream pipeServer = (NamedPipeServerStream)iar.AsyncState;
try
{
// End waiting for the connection
pipeServer.EndWaitForConnection(iar);
byte[] buffer = new byte[255];
// Read the incoming message
pipeServer.Read(buffer, 0, 255);
// Convert byte buffer to string
string stringData = Encoding.UTF8.GetString(buffer, 0, buffer.Length);
Debug.WriteLine(stringData + Environment.NewLine);
// Pass message back to calling form
PipeMessage.Invoke(stringData);
// Kill original server and create new wait server
pipeServer.Close();
pipeServer = null;
pipeServer = new NamedPipeServerStream(_pipeName, PipeDirection.In, 1, PipeTransmissionMode.Message, PipeOptions.Asynchronous);
// Recursively wait for the connection again and again....
pipeServer.BeginWaitForConnection(new AsyncCallback(WaitForConnectionCallBack), pipeServer);
}
catch (Exception ex)
{
string ctch = ex.ToString();
return;
}
}
For handling the pipestream message, delegate to a handler and parse the message:
_pipeServer.PipeMessage += new DelegateMessage(PipesMessageHandler);
at somewhere you need in your code:
_pipeServer.Listen("PipeName");
and parse for example:
private void PipesMessageHandler(string message)
{
if (this.Dispatcher.CheckAccess())
{
this.Dispatcher.Invoke(new NewMessageDelegate(PipesMessageHandler), message);
}
else
{
string pipeMessage = Convert.DateTime(message);
}
}

Using named pipes, how to write messages client receives in its form one by one?

I have a Windows service and a client listening with the following funcionality:
Win service:
Creates named pipe
Creates client process
Waits for connection
Writes to client process
Reads from client
Writes to client process
Reads from client
...
public static bool StartProcessAsCurrentUser()
{
var hUserToken = IntPtr.Zero;
var sInfo = new STARTUPINFO();
var procInfo = new PROCESS_INFORMATION();
var pEnv = IntPtr.Zero;
int iResultOfCreateProcessAsUser;
string cmdLine = "ClientNamedPipeForm.exe";
sInfo.cb = Marshal.SizeOf(typeof(STARTUPINFO));
byte[] buffer = new byte[BUFSIZE];
try
{
var tSecurity = new SECURITY_ATTRIBUTES();
tSecurity.nLength = Marshal.SizeOf(tSecurity);
var pSecurity = new SECURITY_ATTRIBUTES();
pSecurity.nLength = Marshal.SizeOf(pSecurity);
pSecurity.bInheritHandle = true; //For controling handles from child process
IntPtr pointer = Marshal.AllocHGlobal(Marshal.SizeOf(pSecurity));
Marshal.StructureToPtr(pSecurity, pointer, true);
PipeSecurity ps = new PipeSecurity();
System.Security.Principal.SecurityIdentifier sid = new System.Security.Principal.SecurityIdentifier(System.Security.Principal.WellKnownSidType.WorldSid, null);
PipeAccessRule par = new PipeAccessRule(sid, PipeAccessRights.ReadWrite, System.Security.AccessControl.AccessControlType.Allow);
ps.AddAccessRule(par);
NamedPipeServerStream pipeServer = new NamedPipeServerStream("testpipe", PipeDirection.Out, 1, PipeTransmissionMode.Byte, PipeOptions.WriteThrough, 10, 10, ps);
StreamWriter sw = new StreamWriter(pipeServer);
if (!CreateProcessAsUser(hUserToken,
null, // Application Name
cmdLine, // Command Line
IntPtr.Zero,
IntPtr.Zero,
true,
dwCreationFlags,
pEnv,
null, // Working directory
ref sInfo,
out procInfo))
{
throw new Exception("StartProcessAsCurrentUser: CreateProcessAsUser failed.\n");
}
try
{
pipeServer.WaitForConnection();
sw.WriteLine("Waiting");
sw.Flush();
pipeServer.WaitForPipeDrain();
Thread.Sleep(5000);
sw.WriteLine("Waiting2");
sw.Flush();
pipeServer.WaitForPipeDrain();
Thread.Sleep(5000);
sw.WriteLine("Waiting32");
sw.Flush();
pipeServer.WaitForPipeDrain();
Thread.Sleep(5000);
sw.WriteLine("QUIT");
sw.Flush();
pipeServer.WaitForPipeDrain();
}
catch (Exception ex) { throw ex; }
finally
{
if (pipeServer.IsConnected) { pipeServer.Disconnect(); }
}
}
finally
{
//Closing things
}
return true;
}
Client:
Creates named pipe
Connects
Reads from service
Writes in its Form
Writes to service
Reads from service
Writes in its Form
Writes to service
...
private void Client()
{
try
{
IntPtr hPipe;
string dwWritten;
byte[] buffer = new byte[BUFSIZE];
NamedPipeClientStream pipeClient = new NamedPipeClientStream(".","testpipe", PipeDirection.In, PipeOptions.WriteThrough);
if (pipeClient.IsConnected != true) { pipeClient.Connect(); }
StreamReader sr = new StreamReader(pipeClient);
string temp;
bool cont = true;
while (cont)
{
temp = "";
temp = sr.ReadLine();
if (temp != null)
{
listBox1.Items.Add(temp);
listBox1.Refresh();
}
if (temp != "QUIT")
{
sw.WriteLine("Response");
sw.Flush();
pipeClient.WaitForPipeDrain();
}
else
{
sw.WriteLine("Response");
cont = false;
}
}
}
catch (Exception ex)
{
throw new Exception("Exception: " + ex.Message);
}
The problem appears writting to listbox1. Form (and its listbox1) only appears on user screen when the whole process has ended, and it shows the four message at once. I have Thread.Sleep(5000) in service side in order to evidence that each message is written separately, but I'm not sure if process doesn't wait to Thread and I'm testing it wrongly or Form is shown with all messages at once by some reason...

Your problem is the while loop that is blocking the current Thread, this thread is also used to refresh the UI.
1) A poor solution is calling DoEvents() within the while loop. But it would be wise to do more research to implement method 2
2) It's better to create a class that will create a Thread and triggers an event to when a message is received.
For example: (writting online so may contain some syntax/typos) So I will call it PSEUDO code ;-)
public class MessageEventArgs : EventArgs
{
public string Message { get; private set;}
public MessageEventArgs(string message)
{
Message = message;
}
}
public class MyReceiver : IDisposable
{
private Thread _thread;
private ManualResetEvent _terminating = new ManualResetEvent(false);
public void Start()
{
_thread = new Thread(() =>
{
try
{
IntPtr hPipe;
string dwWritten;
byte[] buffer = new byte[BUFSIZE];
NamedPipeClientStream pipeClient = new NamedPipeClientStream(".","testpipe", PipeDirection.In, PipeOptions.WriteThrough);
if (pipeClient.IsConnected != true) { pipeClient.Connect(); }
StreamReader sr = new StreamReader(pipeClient);
string temp;
while(!_terminating.WaitOne(0))
{
temp = "";
temp = sr.ReadLine();
if (temp != null)
{
OnMessage?.Invoke(temp);
}
if (temp != "QUIT")
{
sw.WriteLine("Response");
sw.Flush();
pipeClient.WaitForPipeDrain();
}
else
{
sw.WriteLine("Response");
_terminating.Set();
}
}
}
catch (Exception ex)
{
throw new Exception("Exception: " + ex.Message);
}
});
_thread.Start();
}
public void Dispose()
{
_terminating.Set();
_thread.Join();
}
public event EventHandler<MessageEventArgs> OnMessage;
}
// Example of how to use the Receiver class.
public class Form1: Form
{
MyReceiver _receiver;
public Form1()
{
InitializeComponent();
this.FormClosed += FormClosed;
_receiver = new MyReceiver();
_receiver.OnMessage += MessageReceived;
_receiver.Start();
}
public void MessageReceived(object sender, MessageEventArgs e)
{
// You need to invoke this, because the event is run on other than the UI thread.
this.Invoke(new Action(() =>
{
listBox1.Items.Add(e.Message);
});
}
public void FormClosed(object sender, EventArgs e)
{
_receiver.Dispose();
}
}

application hangs when closing a listening port

I'm using com0com to create a part of virtual ports comA/comB, typing the input to comA from hyperterminal and listening on comB in a wpf application. When I run the following code (by triggering Connect), the application successfully connects and is able to get the data from comA, but hangs when I do Disconnect.
public void Connect()
{
readPort = new SerialPort("COMB");
readPort.WriteTimeout = 500;
readPort.Handshake = Handshake.None;
readPort.Open();
readThread = new Thread(Read);
readRunning = true;
readThread.Start();
System.Diagnostics.Debug.Print("connected");
}
public void Disconnect()
{
if (!readRunning)
{
readPort.Close();
}
else
{
readRunning = false;
readThread.Join();
readPort.Close();
}
System.Diagnostics.Debug.Print("disconnected");
}
public void Read()
{
while (readRunning)
{
try
{
int readData = 0;
readData = readPort.ReadByte();
System.Diagnostics.Debug.Print("message: " + readData.ToString());
}
catch (TimeoutException)
{
}
}
}
I tried changing the Read function to a write by using
byte[] writeData = { 1, 2, 3 };
readPort.Write(writeData, 0, 3);
instead of port.readbyte, and it starts working perfectly when disconnecting. Does anyone know if there is anything different about readbyte that could have caused the freeze? Or is it possibly related to com0com?

Just checking back, in case anyone runs into the same issue, I found an alternative way overriding SerialPort.DataReceived like this:
public override void OnDataReceived(object sender, SerialDataReceivedEventArgs e)
{
SerialPort sp = (SerialPort)sender;
byte[] buf = new byte[sp.BytesToRead];
sp.Read(buf, 0, buf.Length);
receivedDataDel(buf);
}