const
  SemaphoreBasicInformation = 0;

type
  SEMAPHORE_BASIC_INFORMATION = record
    CurrentCount: Integer;
    MaximumCount: Integer;
  end;
  PSEMAPHORE_BASIC_INFORMATION = ^SEMAPHORE_BASIC_INFORMATION;

function NtQuerySemaphore(SemaphoreHandle: THandle;
                          SemaphoreInformationClass: ULONG;
                          SemaphoreInformation: Pointer;
                          SemaphoreInformationLength: ULONG;
                          ReturnLength: PULONG): Integer; stdcall; external 'ntdll.dll';
function RtlNtStatusToDosError(StatusCode: Integer): DWORD; stdcall; external 'ntdll.dll';

function GetSemaphoreInfo(hSemaphore: THandle; var CurrentCount: Integer; var MaximumCount: Integer): Boolean;
var
  sbi: SEMAPHORE_BASIC_INFORMATION;
  Status: Integer;
begin
  Result := false;
  Status := NtQuerySemaphore(hSemaphore,
                             SemaphoreBasicInformation,
                             @sbi,
                             SizeOf(SEMAPHORE_BASIC_INFORMATION),
                             nil);
  if Status >= 0 then
  begin
    CurrentCount := sbi.CurrentCount;
    MaximumCount := sbi.MaximumCount;
    Result := true;
  end
  else
    SetLastError(RtlNtStatusToDosError(Status));
end;