opening acrobat after generating pdf

I'm using the following code snipped to generate pdf since a long time...

static Boolean generateHiresPdf(IDocument* document, IDFile pdfFile)
	{
	InterfacePtr<ICommand> piPDFExportCmd(CmdUtils::CreateCommand(kPDFExportCmdBoss));
	ASSERT(piPDFExportCmd); if (!piPDFExportCmd) return FALSE;

	InterfacePtr<IPDFExportPrefs> piPDFExportPrefs(piPDFExportCmd, UseDefaultIID());
	ASSERT(piPDFExportPrefs); if (!piPDFExportPrefs) return FALSE;

....

    InterfacePtr<ISysFileData> piFileData(piPDFExportCmd, UseDefaultIID());
	ASSERT(piFileData); if (!piFileData) return FALSE;
	piFileData->Set(pdfFile);

	InterfacePtr<IPageList> pageList(document, UseDefaultIID());
	ASSERT(pageList); if (!pageList) return FALSE;

	UIDList pagesUIDList(::GetDataBase(document));
	int32 numPages = pageList->GetPageCount();
	for (int32 i = 0; i < numPages; i++)
		pagesUIDList.Append(pageList->GetNthPageUID(i));

	InterfacePtr<IOutputPages> piOutputPages(piPDFExportCmd, UseDefaultIID());
	ASSERT(piOutputPages); if (!piOutputPages) return FALSE;

	piOutputPages->InitializeFrom(pagesUIDList, kFalse);
	K2::scoped_ptr<RangeProgressBar> deleteProgressBar;
	bool16 bShowImmediate = kTrue;
	RangeProgressBar* progress = new RangeProgressBar("das PDF wird erzeugt...", 0, numPages, bShowImmediate, kTrue, nil, kTrue);
	piPDFExportPrefs->SetProgress(progress);
	deleteProgressBar.reset(progress);

	// and action please
	Boolean ret = (CmdUtils::ProcessCommand(piPDFExportCmd) == kSuccess);

Now some customers want to open Acrobat with this new generated pdf if this flag is set in Indesign. 

 // so far so good, now we reading the flag for opening acrobat or not
	InterfacePtr<IPDFPostProcessPrefs>  appPostProcessPrefs((IPDFPostProcessPrefs*)::QuerySessionPreferences(IID_IPDFPOSTPROCESSPREFS));
	ASSERT(appPostProcessPrefs); if (!appPostProcessPrefs) return ret;
	if (appPostProcessPrefs->GetViewAfterExport()) 
	{
	
	    //??
	}

But I have no idea to do that. At the moment i use 

#if MACOS
...
#else

		ShellExecute(GetIndesignMainWnd(), 0, pdfFile.GrabTString(), 0, 0, SW_SHOW);
#endif
	}

but this is platform dependent. Any idea to to that with the sdk?

thx Holger