Remotely/Shared/Win32/WTSAPI32.cs

using System;
using System.Runtime.InteropServices;

namespace Remotely.Shared.Win32
{
    public static class WTSAPI32
    {
        public static IntPtr WTS_CURRENT_SERVER_HANDLE = IntPtr.Zero;

        public enum WTS_CONNECTSTATE_CLASS
        {
            WTSActive,
            WTSConnected,
            WTSConnectQuery,
            WTSShadow,
            WTSDisconnected,
            WTSIdle,
            WTSListen,
            WTSReset,
            WTSDown,
            WTSInit
        }

        public enum WTS_INFO_CLASS
        {
            WTSInitialProgram,
            WTSApplicationName,
            WTSWorkingDirectory,
            WTSOEMId,
            WTSSessionId,
            WTSUserName,
            WTSWinStationName,
            WTSDomainName,
            WTSConnectState,
            WTSClientBuildNumber,
            WTSClientName,
            WTSClientDirectory,
            WTSClientProductId,
            WTSClientHardwareId,
            WTSClientAddress,
            WTSClientDisplay,
            WTSClientProtocolType,
            WTSIdleTime,
            WTSLogonTime,
            WTSIncomingBytes,
            WTSOutgoingBytes,
            WTSIncomingFrames,
            WTSOutgoingFrames,
            WTSClientInfo,
            WTSSessionInfo
        }


        [DllImport("wtsapi32.dll", SetLastError = true)]
        public static extern int WTSEnumerateSessions(
            System.IntPtr hServer,
            int Reserved,
            int Version,
            ref System.IntPtr ppSessionInfo,
            ref int pCount);

        [DllImport("wtsapi32.dll", ExactSpelling = true, SetLastError = false)]
        public static extern void WTSFreeMemory(IntPtr memory);

        [DllImport("Wtsapi32.dll")]
        public static extern bool WTSQuerySessionInformation(IntPtr hServer, uint sessionId, WTS_INFO_CLASS wtsInfoClass, out IntPtr ppBuffer, out uint pBytesReturned);

        [DllImport("wtsapi32.dll", SetLastError = true)]
        static extern IntPtr WTSOpenServer(string pServerName);

        [StructLayout(LayoutKind.Sequential)]
        public struct WTS_SESSION_INFO
        {
            public uint SessionID;
            [MarshalAs(UnmanagedType.LPStr)]
            public string pWinStationName;
            public WTS_CONNECTSTATE_CLASS State;
        }
    }
}