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How to start a process using Xamarin C# on an android app?

Having this code:
Process checkForUpdates = new Process();
checkForUpdates.StartInfo.FileName = #"python";
checkForUpdates.StartInfo.Arguments = "-V";
checkForUpdates.StartInfo.UseShellExecute = true;
checkForUpdates.StartInfo.RedirectStandardOutput = true;
checkForUpdates.StartInfo.RedirectStandardError = true;
checkForUpdates.StartInfo.CreateNoWindow = false;
checkForUpdates.EnableRaisingEvents = true;
checkForUpdates.Start();
string result = checkForUpdates.StandardOutput.ReadToEnd();
I'm trying retrieve the output of the command python -V in order to determine if python is installed on the device.
The code above compiles but the code seems to hang during the process without any errors. The same code works fine on UWP.
Is there any other way to make it work on Android?

The problem was that I run this code inside a background worker. I put the code in a method directly inside ViewModel and it worked perfectly fine.

Problem redirecting console in C#

i am building a GUI over an console application that i use, i'm trying to use C# Process and RedirectStandardInput/Error/Output.
The problem is when i redirect anything the console applications stops printing data, i've redirected only stdin and watched the console application window itself, nothing, i've redirected stdin, out and err and no data is received by my program.
This is the only application i tested that doesn't work with Std redirection, is it an implementation issue?
Code:
fmproc = new Process();
fmproc.StartInfo.FileName = #"fm.exe";
fmproc.StartInfo.Arguments = "";
fmproc.StartInfo.UseShellExecute = false;
fmproc.StartInfo.CreateNoWindow = false;
fmproc.StartInfo.RedirectStandardInput = true;
fmproc.StartInfo.RedirectStandardError = true;
fmproc.StartInfo.RedirectStandardOutput = true;
fmproc.Start();
fmproc.StandardOutput.ReadLine();

Perhaps you could try:
fmproc.StandardOutput.ReadToEnd();
fmproc.WaitForExit();
Rather than the ReadLine(); Of course you might want to do something more interesting with the output string - but I'm just following your example code.

Getting output from one executable in an other one

I'm currently trying to get the output of an executable console-app into an other one. To be exact, a little overview of what I'm trying to do:
I have one executable which I cannot edit and neither see it's code. It writes some (quite a bunch to be honest) lines into the console when executed.
Now I want to write another executable that starts the one above and reads the things it writes.
Seems simple to me, so I started coding but ended up with an error message saying that StandardOut has not been redirected or the process hasn't started yet.
I tried it using this kinda structure (C#):
Process MyApp = Process.Start(#"C:\some\dirs\foo.exe", "someargs");
MyApp.Start();
StreamReader _Out = MyApp.StandardOutput;
string _Line = "";
while ((_Line = _Out.ReadLine()) != null)
Console.WriteLine("Read: " + _Line);
MyApp.Close();
I can open the executable and it also does open the one inside, but as soon as it comes to reading the returned values, the app crashes.
What am I doing wrong?!

Take a look at the documentation for the Process.StandardOutput property. You will need to set a boolean indicating that you want the stream redirected as well as disabling shell execute.
Note from the documentation:
To use StandardOutput, you must set ProcessStartInfo..::.UseShellExecute to false, and you must set ProcessStartInfo..::.RedirectStandardOutput to true. Otherwise, reading from the StandardOutput stream throws an exception
You would need to change your code a little bit to adjust for the changes:
Process myApp = new Process(#"C:\some\dirs\foo.exe", "someargs");
myApp.StartInfo.UseShellExecute = false;
myApp.StartInfo.RedirectStandardOutput = false;
myApp.Start();
string output = myApp.StandardOutput.ReadToEnd();
p.WaitForExit();

you could try setting processStartInfo.RedirectStandardOutput = true;

As noted above, you can use RedirectStandardOutput as here.
Another, dirtier way is something like
using (Process child = Process.Start
("cmd", #"/c C:\some\dirs\foo.exe someargs > somefilename"))
{
exeProcess.WaitForExit();
}
And then read its output from somefilename

Perl Script Output Capture Problem using C#

I was following one of the thread to run perl scripts from my c# program.
My c# code is like this:
private void RunScript(ArrayList selectedScriptFileList)
{
foreach (var curScriptFileName in selectedScriptFileList)
{
ProcessStartInfo myProcessStartInfo = new ProcessStartInfo("perl.exe");
myProcessStartInfo.Arguments = (string)(curScriptFileName);
myProcessStartInfo.UseShellExecute = false;
myProcessStartInfo.RedirectStandardOutput = true;
myProcessStartInfo.WindowStyle = ProcessWindowStyle.Hidden;
myProcessStartInfo.CreateNoWindow = true;
myProcess.StartInfo = myProcessStartInfo;
myProcess.Start();
myProcess.WaitForExit();
string output = myProcess.StandardOutput.ReadToEnd();
this.ScriptTestResultTextBox.AppendText(output);
}
}
And my perl script requires XML parsing. I can read the print statement before the XML parsing, but not after the parsing starts. The script runs find on DoS shell.
Here is part of my script:
print("\n");
print("****************** test1.pl ***********************\n");
print("\n");
print("1");
print("2");
my $scriptName = 'test1.pl';
my $file = '../../ScriptParamLib.xml';
my $parser = XML::LibXML->new();
my $tree = $parser->parse_file($file);
my $root = $tree->getDocumentElement;
my #species = $root->getElementsByTagName('test_node');
print("Accessing XML Data Base...\n");
The c# testbox only shows the first three print statement but not the last one.
Does anybody knows why?
Thanks

You could add more debugging print statements (e.g. one between every other line of your code) to see how far the execution gets. However, I'm going to go on a hunch and suggest that adding these three lines to your script will either solve the problem outright or lead you closer to a solution:
use strict;
use warnings;
use XML::LibXML;
Please update your question indicating how far execution gets and what errors you see!

I figured I should roll my comments into an answer since they proved to be helpful:
Since using an absolute path for $file in the Perl script works, the issue most likely has something to do with the working directory of the process that gets spawned from the C# program. You can use the Cwd module in the Perl script to see what the working directory actually is. If it's not what you expect, try setting it via the WorkingDirectory property of ProcessStartInfo in your C# program. Relative paths should work just fine after that.

Running console application from C# but application can't create file

I have windows forms application wich runs another console application
here is the part of code
prog = new Process();
prog.StartInfo.FileName = exefile;
The console application should create file but when running that application from C# it doesn't creates any file
when im running console application with double click it works fine
here is the part of code from "exefile" (its on c++)
freopen("file.in","r",stdin);
freopen("file.out","w",stdout);
printf("somedata\n");
"file.in" surely exists

The most likely thing is that you need to set the working path:
prog.StartInfo.WorkingDirectory = ...
i.e. I'm thinking it can't find file.in in the current app folder.

You need to add this line whenever you want to start the process:
prog.Start();
Here is the link to the MSDN page for Process.Start. There are several overloads that you may want to consider.

I would suggest,
handle exceptions to see what's going wrong
like mentioned before make sure you
call the start() method
Here's a snippet of code from msdn, that you might want to refer
Process myProcess = new Process();
try
{
// Get the path that stores user documents.
string myDocumentsPath =
Environment.GetFolderPath(Environment.SpecialFolder.Personal);
myProcess.StartInfo.FileName = myDocumentsPath + "\\MyFile.doc";
myProcess.StartInfo.Verb = "Print";
myProcess.StartInfo.CreateNoWindow = true;
myProcess.Start();
}
catch (Win32Exception e)
{
if(e.NativeErrorCode == ERROR_FILE_NOT_FOUND)
{
Console.WriteLine(e.Message + ". Check the path.");
}
else if (e.NativeErrorCode == ERROR_ACCESS_DENIED)
{
// Note that if your word processor might generate exceptions
// such as this, which are handled first.
Console.WriteLine(e.Message +
". You do not have permission to print this file.");
}
}