Abfragen der Eigenschaften eines Energieschemas

[TiGü]

Ich hatte mich damit mal in Rahmen eines Powershell-Skripts beschäftigt, welches mit dem Windows-Tool powercfg.exe redet.
Es ist wirklich eine API aus der Hölle.
Probiere mal lieber die Index-Funktionen:

Delphi-Quellcode:

program Project5;

{$APPTYPE CONSOLE}
{$R *.res}

uses
  System.SysUtils,
  Winapi.Windows;

function PowerGetActiveScheme(UserRootPowerKey: HKEY; var ActivePolicyGuid: PGUID): DWORD; stdcall;
  external 'PowrProf.dll' name 'PowerGetActiveScheme';

//function PowerReadACValue(RootPowerKey: HKEY; const SchemeGuid: TGUID; const SubGroupOfPowerSettingsGuid: TGUID;
//  const PowerSettingGuid: TGUID; pType: PULONG; Buffer: LPBYTE; BufferSize: LPDWORD): DWORD; stdcall; external 'PowrProf.dll';

function PowerReadACValueIndex(RootPowerKey: HKEY; const SchemeGuid: TGUID; const SubGroupOfPowerSettingsGuid: TGUID;
  const PowerSettingGuid: TGUID; AcValueIndex: LPDWORD): DWORD; stdcall; external 'PowrProf.dll';

const
  USBSetting: TGUID = '{2a737441-1930-4402-8d77-b2bebba308a3}'; // # USB settings
  USBSelectiveSuspendSetting: TGUID = '{48e6b7a6-50f5-4782-a5d4-53bb8f07e226}'; // # USB selective suspend setting
var
  ActivePolicyGuidPtr: PGUID;
  res: DWORD;
  AcValueIndex: DWORD;
  DbgText: string;
begin
  try
    ActivePolicyGuidPtr := nil;
    res := PowerGetActiveScheme(0, ActivePolicyGuidPtr);
    if (res = ERROR_SUCCESS) and Assigned(ActivePolicyGuidPtr) then
    begin
      Writeln('Active Power Scheme GUID: ', TGUID(ActivePolicyGuidPtr^).ToString);
      AcValueIndex := 123456789; // Vorinitialisieren nur um zu sehen, das sich der Wert ändert!
      res := PowerReadACValueIndex(0, TGUID(ActivePolicyGuidPtr^), USBSetting, USBSelectiveSuspendSetting, @AcValueIndex);
      if res = ERROR_SUCCESS then
      begin
        Writeln;
        DbgText := Format('USB settings: %s' + sLineBreak + 'USB selective suspend setting: %s' + sLineBreak +
          'AC Value Index: %d', [USBSetting.ToString, USBSelectiveSuspendSetting.ToString, AcValueIndex]);
        Writeln(DbgText);
      end;

      LocalFree(ActivePolicyGuidPtr);
    end;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
  Readln;

end.