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Exectute a Linux Shell command from ASP.NET Core 3 app

My question is literally, how do I execute a Shell command from my application. There is a similar Post, but that shows how to execute a script file and requires the path to that file.
var process = new Process()
{
StartInfo = new ProcessStartInfo
{
FileName = command, // Path required here
Arguments = args,
RedirectStandardOutput = true,
RedirectStandardError = true,
UseShellExecute = false,
CreateNoWindow = true,
}
};
process.Start();
Why I want to pass the command as a string?
Because I want to interpolate it. Otherwise, I would have to create a script, with some input parameters. Since I'm not that good with Shell, I prefer the easy way.

Assume you want to run echo hello in bash, then
Process process = new Process
{
StartInfo = new ProcessStartInfo
{
FileName = "bash",
RedirectStandardInput = true,
RedirectStandardOutput = true,
RedirectStandardError = true,
UseShellExecute = false
}
};
process.Start();
await process.StandardInput.WriteLineAsync("echo hello");
var output = await process.StandardOutput.ReadLineAsync();
Console.WriteLine(output);

Send Python Output to File from C#

I want to get the output and error messages after running a python script from C#. The output works, however if there's an error in the python script the output returns as "" and I can't get the error. The error displays correctly if the python script is run from Windows shell.
As a workaround I'd like to output from the python script to a txt file and then read the text file in C#. The below works in shell to write for the file mylog.log.
python c:\temp\text.py 2>&1 | tee -filePath mylog.log
If I run the code below in C# no mylog.log file is created.
public string RunFile(string fileName)
{
fileName = #"c:\temp\text.py 2>&1 | tee -filePath c:\temp\myLog.log";
Process p = new Process();
p.StartInfo = new ProcessStartInfo(#"python", fileName)
{
RedirectStandardOutput = true,
UseShellExecute = false,
CreateNoWindow = true,
WorkingDirectory = #"c:\temp"
};
p.Start();
p.WaitForExit();
string output = p.StandardOutput.ReadToEnd();
return output;
}

Thanks for the comments. I've just enabled redirect of the error and am reading the error in C#.
Process p = new Process();
p.StartInfo = new ProcessStartInfo(#"python", fileName)
{
RedirectStandardError = true,
RedirectStandardOutput = true,
UseShellExecute = false,
CreateNoWindow = true,
WorkingDirectory = #"c:\temp"
};
p.Start();
p.WaitForExit();
string output = p.StandardOutput.ReadToEnd();
string error = p.StandardError.ReadToEnd();

Executing Batch File on Remote Server Itself using C#

I need to execute a batch file on remote server itself . I was using the below code as i found as an example but the batch file is getting executing on the application server itself and not on the remote server. If i need to create a log file using the batch file on remote server , it was throwing error stating file path cannot be found .Thanks for the help in advance
if (File.Exists(filePath))
{
var process = new Process();
var startInfo = new ProcessStartInfo
{
CreateNoWindow = true,
FileName = "cmd.exe",
Arguments = "/c \"\"" + filePath + "\"\"",
WorkingDirectory = AppDomain.CurrentDomain.BaseDirectory,
//WorkingDirectory = workingdirectory,
UseShellExecute = false,
RedirectStandardError = true,
RedirectStandardOutput = true
};
process.StartInfo = startInfo;
process.Start();
//process.WaitForExit(30000);
string output = process.StandardOutput.ReadLine();
string errors = process.StandardError.ReadLine();

The work around for executing the batch file on remote server itself is to do a windows scheduler job and trigger the job by some c# code .Please find the below code to do that
string job = #"""\JobLocation\JobName""";
string server = #"XXXXXXXXXXX";
string user = #"Domian\XXXXXX";
string pwd = #"XXXXXXXXXXXXXXX";
string line = #" /run /tn " + job + " /s " + server + " /u " + user + " /p " + pwd;
var process = new Process();
var startInfo = new ProcessStartInfo
{
CreateNoWindow = true,
FileName = #"C:\WINDOWS\SYSTEM32\schtasks.exe",
WindowStyle = ProcessWindowStyle.Hidden,
Arguments = line,
//WorkingDirectory = AppDomain.CurrentDomain.BaseDirectory,
UseShellExecute = false,
RedirectStandardError = true,
RedirectStandardOutput = true
};
process.StartInfo = startInfo;
process.Start();
process.WaitForExit();
string output = process.StandardOutput.ReadLine();
string errors = process.StandardError.ReadLine();code here

Application.exe to open as runas administrator

Hey i am trying to launch my Application.exe as a runas administrator but still not able to launch i have tried both verb="runas" as well as created app.manifest file but my exe not opening in administrator mode.
I am using this code :
var proc = new Process
{
StartInfo = new ProcessStartInfo
{
FileName = GetASDeploymentExe(),
Arguments = GetASDeploymentCmdArgs(),
UseShellExecute = false,
RedirectStandardOutput = true,
RedirectStandardError = true,
CreateNoWindow = true,
Domain = "***",
UserName = username,
Password = secstr,
Verb = "runas"
}
};
proc.Start();
config.ASDeploymentToolPID = proc.Id;
string line = string.Empty;
do
{
line = proc.StandardOutput.ReadLine();
Console.WriteLine(line);
} while (!proc.HasExited);
string error = string.Empty;
while (!proc.StandardError.EndOfStream)
{
error = proc.StandardError.ReadLine();
Logger.WriteError(error);
}
}

Try this:
//Vista or higher check
if (System.Environment.OSVersion.Version.Major >= 6)
{
p.StartInfo.Verb = "runas";
}
Alternatively, go the manifest route for your application.

Running / spawning commands vs files in c#

I can in C# do the following:
var pSpawn = new Process
{
StartInfo = { WorkingDirectory = #"C:\temp", FileName = fileToRun, CreateNoWindow = true }
};
pSpawn.Start();
and this works fine.... however I am wondering if there is a way to run a command (ie: "dir /b") without having to encapsulate it in a batch file?

Just start the cmd.exe and pass the arguments required
var pSpawn = new Process
{
StartInfo =
{
WorkingDirectory = #"C:\temp",
FileName = "cmd.exe",
Arguments ="/K dir /b" }
};
pSpawn.Start();
I have added the parameter /K to leave the command window open so, it is possible to see the output of the command dir.
Of course I think that you are really interested to catch the output of the command.
In this case you could work with something like this:
StringBuilder sb = new StringBuilder();
var pSpawn = new Process
{
StartInfo =
{
WorkingDirectory = #"C:\temp",
FileName = "cmd.exe",
Arguments ="/c dir /b",
CreateNoWindow = true,
RedirectStandardOutput = true,
RedirectStandardInput = true,
UseShellExecute = false
}
};
pSpawn.OutputDataReceived += (sender, args) => sb.AppendLine(args.Data);
pSpawn.Start();
pSpawn.BeginOutputReadLine();
pSpawn.WaitForExit();
Console.WriteLine(sb.ToString());

You can call something like this:
ProcessStartInfo info = new ProcessStartInfo("cmd.exe");
info.Arguments = "/c dir /b";
Process.Start(info);