How do you kill a process for a particular user in .NET (C#)?

Instead of using GetProcessInfoByPID, I just grab the data from StartInfo.EnvironmentVariables.

using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.Security.Principal;
using System.Runtime.InteropServices;

namespace KillRDPClip
{
    class Program
    {
        static void Main(string[] args)
        {
            Process[] processlist = Process.GetProcesses();
            foreach (Process theprocess in processlist)
            {
                String ProcessUserSID = theprocess.StartInfo.EnvironmentVariables["USERNAME"];
                String CurrentUser = Environment.UserName;
                if (theprocess.ProcessName.ToLower().ToString() == "rdpclip" && ProcessUserSID == CurrentUser)
                {
                    theprocess.Kill();
                }
            }
        }
    }
}

Ok, here's what I ended up doing:

           Process[] processlist = Process.GetProcesses();
            bool rdpclipFound = false;

            foreach (Process theprocess in processlist)
            {
                String ProcessUserSID = GetProcessInfoByPID(theprocess.Id);
                String CurrentUser = WindowsIdentity.GetCurrent().Name.Replace("SERVERNAME\\",""); 

                if (theprocess.ProcessName == "rdpclip" && ProcessUserSID == CurrentUser)
                {
                    theprocess.Kill();
                    rdpclipFound = true;
                }

            }
            Process.Start("rdpclip");
            if (rdpclipFound)
            {
               MessageBox.Show("rdpclip.exe successfully restarted"); }
            else
            {
               MessageBox.Show("rdpclip was not running under your username.  It has been started, please try copying and pasting again.");
            }

            }