TestMain.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;

public static class TestMain
{
    static void Main(string[] args)
    {
        var pb = new ProcessArgumentBuilder();
        pb.AddQuoted(args.Skip(1));

        var p = Process.Start(
            new ProcessStartInfo(args[0], pb.ToString()) { UseShellExecute = false, RedirectStandardOutput = true }
        );


        p.WaitForExit();
        string s = p.StandardOutput.ReadToEnd();
        Environment.Exit(p.ExitCode);
    }
}


/// <summary>
/// Builds a process argument string.
/// </summary>
public class ProcessArgumentBuilder
{
    static bool isMono = System.Type.GetType ("Mono.Runtime") != null;

    StringBuilder sb = new StringBuilder();

    /// <summary>Adds an argument, quoting and escaping as necessary.</summary>
    /// <remarks>The .NET process class does not support escaped 
    /// arguments, only quoted arguments with escaped quotes.</remarks>
    public void AddQuoted(string argument)
    {
        if (argument == null)
            return;
        if (sb.Length > 0)
            sb.Append(' ');

        sb.Append('"');
        AppendEscaped(sb, argument);
        sb.Append('"');
    }

    /// <summary>
    /// Adds multiple arguments, quoting and escaping each as necessary.
    /// </summary>
    public void AddQuoted(IEnumerable<string> args)
    {
        foreach (var a in args)
            AddQuoted(a);
    }

    public override string ToString()
    {
        return sb.ToString();
    }

    static void AppendEscaped(StringBuilder sb, string s)
    {
        for (int i = 0; i < s.Length; i++){
            char c = s[i];
            if (c == '"' || (isMono && c == '\\'))
                sb.Append('\\');
            sb.Append(c);
        }
    }
}