private static IEnumerable<int> GetSessionIDs(IntPtr server)
{
// Buffer which contains the SessionInfo structs
IntPtr buffer = IntPtr.Zero;
// Count of structs in this buffer
int count = 0;
// Retrieve all sessions
try
{
if (!Wtsapi32.WtsEnumerateSessions(server, 0, 1, ref buffer, ref count))
throw new Win32Exception("Cannot enumerate wts sessions.");
// Set start of memory location to buffer beginning
IntPtr currentIndex = buffer;
// Iterate over all sessions
for (int i = 0; i < count; i++)
{
var sessionInfo = (Wtsapi32.WtsSessionInfo?) Marshal.PtrToStructure(currentIndex, typeof(Wtsapi32.WtsSessionInfo));
if (sessionInfo == null)
throw new Win32Exception(
"Cannot not marshal session info structure.");
currentIndex += Marshal.SizeOf(typeof(Wtsapi32.WtsSessionInfo));
yield return sessionInfo.Value.SessionId;
}
}
finally
{
// Free memory buffer
Wtsapi32.WtsFreeMemory(buffer);
}
}
private static string? GetUsername(IntPtr server, int sessionId)
{
IntPtr buffer = IntPtr.Zero;
try
{
// Check is method returns success
if (!Wtsapi32.WtsQuerySessionInformation(server, sessionId, Wtsapi32.WtsInfoClass.WtsUserName, out buffer,
out uint _))
return null;
return Marshal.PtrToStringAnsi(buffer)?.ToUpper().Trim();
}
finally
{
Wtsapi32.WtsFreeMemory(buffer);
}
}
