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C#: Calling a php script and beeing able to stop it

I am currently working on a C# Program which needs to call a local PHP script and write its output to a file. The problem is, that I need to be able to stop the execution of the script.
First, I tried to call cmd.exe and let cmd write the output to the file which worked fine. But I found out, that killing the cmd process does not stop the php cli.
So I tried to call php directly, redirect its output and write it from the C# code to a file. But here the problem seems to be, that the php cli does not terminate when the script is done. process.WaitForExit() does not return, even when I am sure that the script has been fully executed.
I cannot set a timeout to the WaitForExit(), because depending on the arguments, the script may take 3 minutes or eg. 10 hours.
I do not want to kill just a random php cli, there may be others currently running.
What is the best way to call a local php script from C#, writing its output to a file and beeing able to stop the execution?
Here is my current code:
// Create the process
var process = new System.Diagnostics.Process();
process.EnableRaisingEvents = true;
process.StartInfo.UseShellExecute = false;
process.StartInfo.FileName = "php.exe";
// CreateExportScriptArgument returns something like "file.php arg1 arg2 ..."
process.StartInfo.Arguments = CreateExportScriptArgument(code, this.content, this.options);
process.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
process.StartInfo.RedirectStandardOutput = true;
// Start the process or cancel, if the process should not run
if (!this.isRunning) { return; }
this.currentProcess = process;
process.Start();
// Get the output
var output = process.StandardOutput;
// Wait for the process to finish
process.WaitForExit();
this.currentProcess = null;
To kill the process I am using:
// Mark as not running to prevent starting new
this.isRunning = false;
// Kill the process
if (this.currentProcess != null)
{
this.currentProcess.Kill();
}
Thanks for reading!
EDIT
That the cli does not return seems to be not reproducible. When I test a different script (without arguments) it works, probably its the script or the passing of the arguments.
Running my script from cmd works just fine, so the script should not be the problem
EDIT 2
When disabling RedirectStandardOutput, the cli quits. could it be, that I need to read the output, before the process finishes? Or does the process wait, when some kind of buffer is full?
EDIT 3: Problem solved
Thanks to VolkerK, I / we found a solution. The problem was, that WaitForExit() did not get called, when the output is not read (probably due to a full buffer in the standard output). My script wrote much output.
What works for me:
process.Start();
// Get the output
var output = process.StandardOutput;
// Read the input and write to file, live to avoid reading / writing to much at once
using (var file = new StreamWriter("path\\file", false, new UTF8Encoding()))
{
// Read each line
while (!process.HasExited)
{
file.WriteLine(output.ReadLine());
}
// Read the rest
file.Write(output.ReadToEnd());
// flush to file
file.Flush();
}

Since the problem was that the output buffer was full and therefore the php process stalled while waiting to send its output, asynchronously reading the output in the c# program is the solution.
class Program {
protected static /* yeah, yeah, it's only an example */ StringBuilder output;
static void Main(string[] args)
{
// Create the process
var process = new System.Diagnostics.Process();
process.EnableRaisingEvents = true;
process.StartInfo.UseShellExecute = false;
process.StartInfo.FileName = "php.exe";
process.StartInfo.Arguments = "-f path\\test.php mu b 0 0 pgsql://user:pass#x.x.x.x:5432/nominatim";
process.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
process.StartInfo.RedirectStandardOutput = true;
output = new StringBuilder();
process.OutputDataReceived += process_OutputDataReceived;
// Start the process
process.Start();
process.BeginOutputReadLine();
// Wait for the process to finish
process.WaitForExit();
Console.WriteLine("test");
// <-- do something with Program.output here -->
Console.ReadKey();
}
static void process_OutputDataReceived(object sender, System.Diagnostics.DataReceivedEventArgs e)
{
if (!String.IsNullOrEmpty(e.Data)) {
// edit: oops the new-line/carriage-return characters are not "in" e.Data.....
// this _might_ be a problem depending on the actual output.
output.Append(e.Data);
output.Append(Environment.NewLine);
}
}
}
see also: https://msdn.microsoft.com/en-us/library/system.diagnostics.process.beginoutputreadline%28v=vs.110%29.aspx

Is there a C# way to read exceptions from cmd processes?

The specific problem I am seeing when executing a cmd process with something like "del *.txt" where one of the 'txt' files is open and cannot be deleted, the cmd process will output a line of text (saying something like 'file in use, cannot delete file') to the console, but not to the StandardOutput or the StandardError. According to this question [ https://stackoverflow.com/a/320779/832705 ] from 2008, the answer is no, but I am wondering if that might have changed in the past 4 years, or if someone has since found a workaround way. Also, I might be misinterpreting that answer, it might mean CLR exceptions and not cmd exceptions.
here is my process setup/start code:
ProcessStartInfo psi = new ProcessStartInfo("cmd", string.Empty);
psi.CreateNoWindow = true;
psi.ErrorDialog = false;
psi.RedirectStandardError = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardInput = true;
psi.UseShellExecute = false;
Process p = new Process();
p.StartInfo = psi;
p.OutputDataReceived += new DataReceivedEventHandler(p_OutputDataReceived);
p.ErrorDataReceived += new DataReceivedEventHandler(p_ErrorDataReceived);
outputfilesw = new StreamWriter(outputfile, true);
try
{
p.Start();
p.BeginOutputReadLine();
//work code
}

You just have to call p.BeginErrorReadLine() to start the asynchronous read of StandardError. Answer added at suggestion of OP.

You can read the output, and you can process the text returned. So, you should be able to find the text that indicates an error, even if it doesn't land in the error output.
Also, it is important to note that only the process being run can determine which output stream gets a message. So, if the command you're using decides to send errors to the standard stream, no amount of OS or C# work will change that.

Is there any cmd callback?

Obviously I can execute something with cmd console using Process.Start();
Is there any way to get output of that process? For example, I could have something like...
Process.Start("sample.bat");
... in my C# winforms application and sample.bat will contain something like:
echo sample loaded
First Question: is there any way to retrieve that sample loaded, after bat execution?
Second question: is there a way to use it without popped up console window?

There is an example of exactly how to do this in the Process documentation:
// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "Write500Lines.exe";
p.Start();
// Do not wait for the child process to exit before
// reading to the end of its redirected stream.
// p.WaitForExit();
// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();

Yes, you can use
Process.Start(ProcessStartInfo)
There are a few ways to hook into I/O including ProcessStartInfo.RedirectStandardOutput available. You can use these overloads to read output from your batch files. You can also hook into the Exited event to know when execution is complete.
Use CreateNoWindow for no window.

Set process.StartInfo.RedirectStandardOutput to true and subscribe to process.OutputDataReceived
using (var process = new Process())
{
process.StartInfo = new ProcessStartInfo("exename");
process.StartInfo.RedirectStandardOutput = true;
process.OutputDataReceived += (s, ev) =>
{
string output = ev.Data;
};
process.Start();
process.BeginOutputReadLine();
process.WaitForExit();
}

Showing output of a running cmd process

I have a C# code that uses command prompt to call a python script. The script currently takes about 25 seconds to run. When run in command prompt, the python script has several outputs until finally outputting "done". My C# code runs the script, but never closes the command prompt if I use "WaitForExit". So my thought is I need some kind of logic to check to see if "done" has been outputted, but the internet has not been very helpful with methodology.
Here's what I have, it currently only outputs the first line, "Microsoft Windows [Version 6.1.7601]". Obviously, no good.
var p = new Process();
p.StartInfo.FileName = "cmd.exe";
p.StartInfo.WorkingDirectory = #"C:\Optimization";
p.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardInput = true;
p.Start();
p.StandardInput.WriteLine(#"ipy spot_for_labview.py");
StreamReader mySR = p.StandardOutput;
string mystr = mySR.ReadLine();
Debug.WriteLine(mystr);
p.WaitForExit(25000); //25000 is a placeholder until better method found.
p.Close();
If there's anyway to close the process after it finishes, or to get all the cmd output I'm all ears.
Any help is appreciated.

did you try this event ? Process.OutputDataReceived Event
or Process.ErrorDataReceived Event
here is the code from MSDN
Process sortProcess;
sortProcess = new Process();
sortProcess.StartInfo.FileName = "Sort.exe";
sortProcess.OutputDataReceived += new DataReceivedEventHandler(SortOutputHandler);
...
....
...
private static void SortOutputHandler(object sendingProcess,
DataReceivedEventArgs outLine)
{
}

C# Process - Pause or sleep before completion

I have a Process:
Process pr = new Process();
pr.StartInfo.FileName = #"wput.exe";
pr.StartInfo.Arguments = #"C:\Downloads\ ftp://user:dvm#172.29.200.158/Transfer/Updates/";
pr.StartInfo.RedirectStandardOutput = true;
pr.StartInfo.UseShellExecute = false;
pr.StartInfo.
pr.Start();
string output = pr.StandardOutput.ReadToEnd();
Console.WriteLine("Output:");
Console.WriteLine(output);
Wput is an ftp upload client.
At the moment when I run the process and begin the upload, the app freezes and the console output won't show until the end. I guess the first problem is solvable by using a Thread.
What I want to do is start an upload, have it pause every so often, read whatever output has been generated (use this data do make progress bar etc), and begin again.
What classes/methods should I be looking into?

You can use the OutputDataReceived event to print the output asynchronously. There are a few requirements for this to work:
The event is enabled during asynchronous read operations on StandardOutput. To start asynchronous read operations, you must redirect the StandardOutput stream of a Process, add your event handler to the OutputDataReceived event, and call BeginOutputReadLine. Thereafter, the OutputDataReceived event signals each time the process writes a line to the redirected StandardOutput stream, until the process exits or calls CancelOutputRead.
An example of this working is below. It's just doing a long running operation that also has some output (findstr /lipsn foo * on C:\ -- look for "foo" in any file on the C drive). The Start and BeginOutputReadLine calls are non-blocking, so you can do other things while the console output from your FTP application rolls in.
If you ever want to stop reading from the console, use the CancelOutputRead/CancelErrorRead methods. Also, in the example below, I'm handling both standard output and error output with a single event handler, but you can separate them and deal with them differently if needed.
using System;
using System.Diagnostics;
namespace AsyncConsoleRead
{
class Program
{
static void Main(string[] args)
{
Process p = new Process();
p.StartInfo.FileName = "findstr.exe";
p.StartInfo.Arguments = "/lipsn foo *";
p.StartInfo.WorkingDirectory = "C:\\";
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.RedirectStandardError = true;
p.OutputDataReceived += new DataReceivedEventHandler(OnDataReceived);
p.ErrorDataReceived += new DataReceivedEventHandler(OnDataReceived);
p.Start();
p.BeginOutputReadLine();
p.WaitForExit();
}
static void OnDataReceived(object sender, DataReceivedEventArgs e)
{
Console.WriteLine(e.Data);
}
}
}

The best method would be to use libraries which support FTP, instead of relying on external applications. If you don't need much info from the external application and are not verifying their outputs, then go ahead. Else better use FTP client libs.
May be you would like to see libs/documentations:
http://msdn.microsoft.com/en-us/library/ms229711.aspx
http://www.codeproject.com/KB/IP/ftplib.aspx
http://www.c-sharpcorner.com/uploadfile/danglass/ftpclient12062005053849am/ftpclient.aspx