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C# Redirect other console app StandardOutput fail if I won't close StardandInput

I've got a tricky issue with a console app, from which I'm trying to redirect StandardInput, StandardOutput and StandardError.
I've got a working solution for other console app - that's not a new thing for me. But this app seems to have something special, which is making impossible to redirect all outputs with a standard approach.
Console app works like this:
directly after startup writes a few lines and waits for user input
no matter what input is - console app is showing some output and again wait for new input
console app never ends, it has to be closed
I've tried already solutions based on:
StandardOutput/Error.ReadToEnd()
taki care of OutputDataReceived & ErrorDataReceived with read line by line with ReadLine
reading by char
waiting for the end of process (which is not ending, so I'm running into a deadlock)
to start console app in a preloaded cmd.exe and grab this (StandardOutput stopped to show just after launch of this console app)
to manually flush input
All the time I had completely no output and no error stream from console app - nothing.
After a multitude attempts I've discovered, that I can receive StandardOutput only when I'll close StandardInput after programatically inputting the data.
But in this case, console app is going wild, falling into loop of writing few lines to StandardOutput as on start-up, which makes final output big and full of garbages.
With MedallionShell library I'm able to try to gracefully kill it with Ctrl+C, but this solution is still far from acceptable, because:
sometimes console app will produce so much garbages before I will be able to kill it, that it crashes my app
even if this won't crash, searching for expected output in a lot of garbages is nasty and tragically slows down automatization (6000 records in... 15 minutes)
I'm unable to provide more than one input at a time, so I have to start console app just to receive one output, close and start again for another output
I've got no sources for that console app, so I'm even not able to recreate the issue or fix it - it's some very legacy app at my company, which I'm trying to make at least a bit automatic...
Code, with which I've got at least anything now (with MediallionShell):
var command = Command.Run(Environment.CurrentDirectory + #"\console_app.exe");
command.StandardInput.WriteLine("expected_input");
command.StandardInput.Close(); // without that I'll never receive any output or error stream from this stubborn console app
command.TrySignalAsync(CommandSignal.ControlC); // attempt to kill gracefully, not always successfull...
var result = command.Result;
textBox1.AppendText(String.Join(Environment.NewLine, command.GetOutputAndErrorLines().ToArray().Take(10))); // trying to get rid of garbages
command.Kill(); // additional kill attempt if Ctrl+C didn't help, sometimes even this fails
Any help will be appreciated, I'm also still searching for solution and now I'm checking this one: PostMessage not working with console window whose output is redirected and read asynchronously but author there had an output and I don't...

You haven't provided a sample Console program to test with, but something like the following may work:
Create a Console project (Console (.NET Framework)) - used for testing
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleTestApp
{
class Program
{
static void Main(string[] args)
{
//prompt for input - 1st prompt
Console.Write("Please enter filename: ");
string filename = Console.ReadLine();
if (System.IO.File.Exists(filename))
{
Console.WriteLine("'" + filename + "' exists.");
}
else
{
Console.Error.WriteLine("'" + filename + "' doesn't exist.");
}
//prompt for input - 2nd prompt
Console.Write("Would you like to exit? ");
string answer = Console.ReadLine();
Console.WriteLine("Your answer was: " + answer);
Console.WriteLine("Operation complete.");
}
}
}
Then, create a Windows Forms project Windows Forms (.NET Framework) and run one of the following:
Option 1:
private void RunCmd(string exePath, string arguments = null)
{
//create new instance
ProcessStartInfo startInfo = new ProcessStartInfo(exePath, arguments);
startInfo.Arguments = arguments; //arguments
startInfo.CreateNoWindow = true; //don't create a window
startInfo.RedirectStandardError = true; //redirect standard error
startInfo.RedirectStandardOutput = true; //redirect standard output
startInfo.RedirectStandardInput = true;
startInfo.UseShellExecute = false; //if true, uses 'ShellExecute'; if false, uses 'CreateProcess'
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.ErrorDialog = false;
//create new instance
using (Process p = new Process { StartInfo = startInfo, EnableRaisingEvents = true })
{
//subscribe to event and add event handler code
p.ErrorDataReceived += (sender, e) =>
{
if (!String.IsNullOrEmpty(e.Data))
{
//ToDo: add desired code
Debug.WriteLine("Error: " + e.Data);
}
};
//subscribe to event and add event handler code
p.OutputDataReceived += (sender, e) =>
{
if (!String.IsNullOrEmpty(e.Data))
{
//ToDo: add desired code
Debug.WriteLine("Output: " + e.Data);
}
};
p.Start(); //start
p.BeginErrorReadLine(); //begin async reading for standard error
p.BeginOutputReadLine(); //begin async reading for standard output
using (StreamWriter sw = p.StandardInput)
{
//provide values for each input prompt
//ToDo: add values for each input prompt - changing the for loop as necessary
for (int i = 0; i < 2; i++)
{
if (i == 0)
sw.WriteLine(#"C:\Temp\Test1.txt"); //1st prompt
else if (i == 1)
sw.WriteLine("Yes"); //2nd prompt
else
break; //exit
}
}
//waits until the process is finished before continuing
p.WaitForExit();
}
}
Option 2:
private void RunCmd(string exePath, string arguments = null)
{
//create new instance
ProcessStartInfo startInfo = new ProcessStartInfo(exePath, arguments);
startInfo.Arguments = arguments; //arguments
startInfo.CreateNoWindow = true; //don't create a window
startInfo.RedirectStandardError = true; //redirect standard error
startInfo.RedirectStandardOutput = true; //redirect standard output
startInfo.RedirectStandardInput = true;
startInfo.UseShellExecute = false; //if true, uses 'ShellExecute'; if false, uses 'CreateProcess'
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.ErrorDialog = false;
//create new instance
using (Process p = new Process { StartInfo = startInfo, EnableRaisingEvents = true })
{
//subscribe to event and add event handler code
p.ErrorDataReceived += (sender, e) =>
{
if (!String.IsNullOrEmpty(e.Data))
{
//ToDo: add desired code
Debug.WriteLine("Error: " + e.Data);
}
};
//subscribe to event and add event handler code
p.OutputDataReceived += (sender, e) =>
{
if (!String.IsNullOrEmpty(e.Data))
{
//ToDo: add desired code
Debug.WriteLine("Output: " + e.Data);
}
};
p.Start(); //start
p.BeginErrorReadLine(); //begin async reading for standard error
p.BeginOutputReadLine(); //begin async reading for standard output
using (StreamWriter sw = p.StandardInput)
{
//provide values for each input prompt
//ToDo: add values for each input prompt - changing the for loop as necessary
sw.WriteLine(#"C:\Temp\Test1.txt"); //1st prompt
sw.WriteLine("Yes"); //2nd prompt
}
//waits until the process is finished before continuing
p.WaitForExit();
}
}
Option 3:
Note: This one is modified from here.
private void RunCmd(string exePath, string arguments = null)
{
//create new instance
ProcessStartInfo startInfo = new ProcessStartInfo(exePath, arguments);
startInfo.Arguments = arguments; //arguments
startInfo.CreateNoWindow = true; //don't create a window
startInfo.RedirectStandardError = true; //redirect standard error
startInfo.RedirectStandardOutput = true; //redirect standard output
startInfo.RedirectStandardInput = true;
startInfo.UseShellExecute = false; //if true, uses 'ShellExecute'; if false, uses 'CreateProcess'
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.ErrorDialog = false;
//create new instance
using (Process p = new Process { StartInfo = startInfo, EnableRaisingEvents = true })
{
p.Start(); //start
Read(p.StandardOutput);
Read(p.StandardError);
using (StreamWriter sw = p.StandardInput)
{
//provide values for each input prompt
//ToDo: add values for each input prompt - changing the for loop as necessary
sw.WriteLine(#"C:\Temp\Test1.txt"); //1st prompt
sw.WriteLine("Yes"); //2nd prompt
}
//waits until the process is finished before continuing
p.WaitForExit();
}
}
private static void Read(StreamReader reader)
{
new System.Threading.Thread(() =>
{
while (true)
{
int current;
while ((current = reader.Read()) >= 0)
Console.Write((char)current);
}
}).Start();
}

How to execute a hidden Process that requires user interaction without blocking?

Please don’t mark as duplicate before read.
After looking a lot of google search I found a lot of code. All the codes are okay but my problem is little bit more.
Suppose, I can execute ‘dir’ command using this below code which gives me perfect output:
static void Main(string[] args)
{
var str=ExecuteCommand("/c dir");
//var str=ExecuteCommand("/c chkdsk C: /f/r/x");
MessageBox.Show(str);
}
static string ExecuteCommand(string cmd)
{
Process proc = new Process();
proc.StartInfo.FileName = "cmd.exe";
proc.StartInfo.Arguments = cmd;
proc.StartInfo.UseShellExecute = false;
proc.StartInfo.RedirectStandardOutput = true;
proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
proc.StartInfo.CreateNoWindow = true;
proc.Start();
string output = proc.StandardOutput.ReadToEnd();
return output;
}
But, when I run this command “/c chkdsk C: /f/r/x” then no output comes because it waits for user input(y/n). I want to view output and send y or n from my C# code not by cmd console window.

How to identify if a Process needs input? [duplicate]

This question already has answers here:
C# StandardOutput hangs, how can I detect it's waiting for input?
(2 answers)
Closed 3 years ago.
I am running a command prompt utility using System.Diagnostics.Process class in .NET Framework. This command prompt utility might need some user input in some cases and also sometimes it finishes the task without needing any input from user.
Here is what I have done to run this process:
var process = new Process();
process.StartInfo = new ProcessStartInfo([PATH_TO_EXE], arguments);
process.StartInfo.RedirectStandardError = true;
process.StartInfo.RedirectStandardInput = true;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.UseShellExecute = false;
process.Start();
The problem is I don't know how to identify if this process needs input or not?

The only thing I could find that worked. No matter how short or long the response was. Is too add an echo after you send a command like so. Than just check for the echo to know when to stop waiting.
var process = new Process();
process.StartInfo.UseShellExecute = false;
process.StartInfo.CreateNoWindow = true;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.FileName = Settings.MongoPath;
// Redirects the standard input so that commands can be sent to the shell.
process.StartInfo.RedirectStandardInput = true;
process.StartInfo.Arguments = ConnString;
process.Start();
// this is key, this returns 1 once previous command in argument is done executing
process.StandardInput.WriteLine("{ping:1}");
var current_line = string.Empty;
var OutputList = new List<string>();
while (!process.StandardOutput.EndOfStream)
{
current_line = process.StandardOutput.ReadLine();
if (current_line == "1")
{
// command is done executing
break;
}
OutputList.Add(current_line);
}
// contains all of the out put of the command
OutputList

How to run a batch file within a C# GUI form

How would you execute a batch script within a GUI form in C#
Could anyone provide a sample please?

System.Diagnotics.Process.Start("yourbatch.bat"); ought to do it.
Another thread covering the same issue.

This example assumes a Windows Forms application with two text boxes (RunResults and Errors).
// Remember to also add a using System.Diagnostics at the top of the class
private void RunIt_Click(object sender, EventArgs e)
{
using (Process p = new Process())
{
p.StartInfo.WorkingDirectory = "<path to batch file folder>";
p.StartInfo.FileName = "<path to batch file itself>";
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.RedirectStandardError = true;
p.Start();
p.WaitForExit();
// Capture output from batch file written to stdout and put in the
// RunResults textbox
string output = p.StandardOutput.ReadToEnd();
if (!String.IsNullOrEmpty(output) && output.Trim() != "")
{
this.RunResults.Text = output;
}
// Capture any errors written to stderr and put in the errors textbox.
string errors = p.StandardError.ReadToEnd();
if (!String.IsNullOrEmpty(errors) & errors.Trim() != ""))
{
this.Errors.Text = errors;
}
}
}
Updated:
The sample above is a button click event for a button called RunIt. There's a couple of text boxes on the form, RunResults and Errors where we write the results of stdout and stderr to.

I deduce that by executing within a GUI form you mean showing execution results within some UI-Control.
Maybe something like this:
private void runSyncAndGetResults_Click(object sender, System.EventArgs e)
{
System.Diagnostics.ProcessStartInfo psi =
new System.Diagnostics.ProcessStartInfo(#"C:\batch.bat");
psi.RedirectStandardOutput = true;
psi.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
psi.UseShellExecute = false;
System.Diagnostics.Process batchProcess;
batchProcess = System.Diagnostics.Process.Start(psi);
System.IO.StreamReader myOutput = batchProcess.StandardOutput;
batchProcess.WaitForExit(2000);
if (batchProcess.HasExited)
{
string output = myOutput.ReadToEnd();
// Print 'output' string to UI-control
}
}
Example taken from here.

Realtime Console Output Redirection using Process

I am using VBOXMANAGE to "export" a guest machine. VBOXManage is a Console application that can control the guest machine's behavior from the host. Since the export command is a long process, it returns process updates like so:
0%...10%...20%...30%...100%
I am writing a C# application that will invoke VBOXManage using Process. Here's my code:
Process VBOXProc = new Process();
VBOXProc.StartInfo.FileName = VBOXMANAGE;
VBOXProc.StartInfo.Arguments = Arguments;
VBOXProc.StartInfo.UseShellExecute = false;
VBOXProc.StartInfo.CreateNoWindow = true;
VBOXProc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
VBOXProc.StartInfo.RedirectStandardError = true;
VBOXProc.StartInfo.RedirectStandardOutput = true;
VBOXProc.OutputDataReceived += new DataReceivedEventHandler(VBOXProc_OutputDataReceived);
VBOXProc.ErrorDataReceived += new DataReceivedEventHandler(VBOXProc_ErrorDataReceived);
VBOXProc.EnableRaisingEvents = true;
VBOXProc.Start();
VBOXProc.BeginOutputReadLine();
VBOXProc.BeginErrorReadLine();
VBOXProc.WaitForExit();
This is fine, except that the output is being read per LINE. This means that the process updates "
0%...10%...20%...30%...100%" will only show AFTER the actual process is done.
Is there a way to capture the console output in realtime?
Thanks!

This worked for me:
process.StartInfo.CreateNoWindow = true;
process.StartInfo.ErrorDialog = false;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.UseShellExecute = false;
process.ErrorDataReceived += (sendingProcess, errorLine) => error.AppendLine(errorLine.Data);
process.OutputDataReceived += (sendingProcess, dataLine) => SetMessage(dataLine.Data);
process.Start();
process.BeginErrorReadLine();
process.BeginOutputReadLine();
process.WaitForExit();
error.AppendLine() and SetMessage() are the methods I used.

You can read directly from the StanadardOutput/Error for the process using all the standard Stream methods, just be sure to set the StartInfo.Redirectxxx to true.
var p = new Process()
p.StartInfo.UseShellExecute = false; //not sure if this is absolutely required
p.StartInfo.RedirectStandardOuput = true;
....
do
{
Thread.Sleep(nnn);
Console.Out.Write(p.StandardOutput.ReadToEnd());
}
while (!p.HasExited);
//catch any leftovers in redirected stdout
Console.Out.Write(p.StandardOutput.ReadToEnd());
The above will echo the output of the child process to your applications Standard Out.
You can read Blocks of a particular size using p.StandardOutput.Read(char[], int, int) or asynchronous reads using p.StadardOutput.BaseStream.BeginRead(...).
All the same methods are available for StandardError.
Sleeping in the loop frees up the processor for other tasks and allows some data to accumulate in the bufffer. If the sleep period is too long and the buffer overflows some output from the executing process will be lost. If the sleep period is too short a lot of CPU cycles are spent reading and empty buffer.

Try to redirect standard input too and apply AutoFlush to StandardInput. Next read stream using StreamReader.
Process proces;
ProcessStartInfo psi = new ProcessStartInfo();
psi.FileName = "test.exe";
psi.UseShellExecute = false;
psi.CreateNoWindow = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardInput = true;
proces = Process.Start(psi);
proces.StandardInput.AutoFlush = true;

Sorry any mistake, I am Brazilian and to using Google Translate to write this text.
Coincidentally, I also'm doing a program that works with VBoxManage of Virtualbox. In my case I wanted, among other things, convert a virtual disk. Also it delays and the percentage with progress also
I managed to do just this by creating a process of will to run the program, and using a user classes 'Dean North` the other question that is similar to this. It is important to use a thread to run the VBoxManage, otherwise has no way to work the obtained text or view the progress.
O texto é muito grande pra eu adicionar quatro espaços antes de cada linha e repassar.
The classes replace the Process system class. Need not make any changes to your code, just add a arquivo.cs with the text passed by the user Dean North instead of Process p = new Process() use FixedProcess p = new FixedProcess ()
After that it was my code:
private void BotaoParaTestes_Click(object sender, EventArgs e)
{
string linha = #"clonehd " +
"\"Z:\\Máquinas Virtuais\\Teste.vdi\" " +
"\"C:\\Temp\\teste.vdi\" " +
"--format VDI --variant Standard";
Thread tarefa = new Thread(Executar);
tarefa.Start(linha);
}
private void Executar(object Linha)
{
FixedProcess fp = new FixedProcess ();
fp.StartInfo.FileName = ItensEstaticos.VBox;
fp.StartInfo.Arguments = Linha.ToString();
fp.StartInfo.CreateNoWindow = true;
fp.StartInfo.ErrorDialog = false;
fp.StartInfo.RedirectStandardError = true;
fp.StartInfo.RedirectStandardOutput = true;
fp.StartInfo.UseShellExecute = false;
fp.ErrorDataReceived += (sendingProcess, errorLine) => Escrita(errorLine.Data);
fp.OutputDataReceived += (sendingProcess, dataLine) => Escrita(dataLine.Data);
fp.Start();
fp.BeginErrorReadLine();
fp.BeginOutputReadLine();
fp.WaitForExit();
}
private void Escrita(string Texto)
{
if (!string.IsNullOrEmpty(Texto))
{
BeginInvoke(new MethodInvoker(delegate
{
this.Texto.Text += Texto;
}));
}
}
For me the event is only called when the text is changed, not only when the VBoxManage goes to a new line. Sometimes the text was null, then place a check structure as I did before using the text obtained for controls.