Dos command in c# - RedirectStandardError/Output problem

Question

Hello, I need to run Dos commands within a class. My problem is that the redirect options seem to prevent the command from running.
Here is my code:

public static int executeCommand(string cmd)
    {
        System.Diagnostics.ProcessStartInfo processStartInfo = new System.Diagnostics.ProcessStartInfo("CMD.exe", "/C " + cmd);
        int exitCode = 0;
        //processStartInfo.RedirectStandardError = true;
        //processStartInfo.RedirectStandardOutput = true;
        processStartInfo.CreateNoWindow = true;
        processStartInfo.UseShellExecute = false;
        System.Diagnostics.Process process =
        System.Diagnostics.Process.Start(processStartInfo);

        process.WaitForExit(); //wait for 20 sec
        exitCode = process.ExitCode;
        //string stdout = process.StandardOutput.ReadToEnd();
        //string stderr = process.StandardError.ReadToEnd();
        process.Close();
        return exitCode;
    }

When I call xcopy:

if (executeCommand("xcopy.exe " + "/E /I /R /Y /Q c:\\temp\\*.* e:\\temp\\b1\\ ") != 0)
                Log.Error("Error detected running xcopy ");

The method correctly runs xcopy. If I want to redirect the SDTOUT and STDERR, the method returns 0 as well but xcopy didn't really run.

In other words, this doesn't work:

public static int executeCommand(string cmd)
    {
        System.Diagnostics.ProcessStartInfo processStartInfo = new System.Diagnostics.ProcessStartInfo("CMD.exe", "/C " + cmd);
        int exitCode = 0;
        processStartInfo.RedirectStandardError = true;
        processStartInfo.RedirectStandardOutput = true;
        processStartInfo.CreateNoWindow = true;
        processStartInfo.UseShellExecute = false;
        System.Diagnostics.Process process =
        System.Diagnostics.Process.Start(processStartInfo);

        process.WaitForExit(); //wait for 20 sec
        exitCode = process.ExitCode;
        string stdout = process.StandardOutput.ReadToEnd();
        string stderr = process.StandardError.ReadToEnd();
        process.Close();
        return exitCode;
    }

Any idea why?

Thanks

tony

Answer 1

It is quirk of xcopy.exe, you must redirect stdin as well. Check this thread for my original diagnostic. No need to use cmd.exe btw, just call xcopy directly.