Introduction
Windows introduced a new concept when it let the user add new handlers to the
shell, such as a context menu handler, icon handler
and also for other applications such as the cleanup manager.
Generally all the handlers implement a certain interface
(one or more) and register the component by adding some keys to the registry.
Implementation
This Application is a simple COM component that implement the IEmptyVolumeCache2
interface
and its 6 methods.
Class CExtHandler : public IEmptyVolumeCache2 {
...
STDMETHODIMP Initialize(
HKEY hkRegKey,
LPCWSTR pcwszVolume,
LPWSTR *ppwszDisplayName,
LPWSTR *ppwszDescription,
DWORD *pdwFlags);
STDMETHODIMP GetSpaceUsed(
DWORDLONG *pdwlSpaceUsed,
IEmptyVolumeCacheCallBack *picb);
STDMETHODIMP Purge(
DWORDLONG dwlSpaceToFree,
IEmptyVolumeCacheCallBack *picb);
STDMETHODIMP ShowProperties(HWND hwnd);
STDMETHODIMP Deactivate(DWORD *pdwFlags);
STDMETHODIMP InitializeEx (HKEY hKey, LPCWSTR pcwszVolume, LPCWSTR pcwszKeyName,
LPWSTR *ppwszDisplayName, LPWSTR *ppwszDescription,
LPWSTR *ppwszBtnText, DWORD *pdwFlags);
How it works:
- You first register the server (through regsrv32.exe, or indirectly by reg.bat)
and you'll be presented with
a dialog box, where you could fill the fields appropriately or let those default
values, if you want the clean
handler to delete the intermediate visual c++ files. - Once the extension is registered, it can be accessed by starting CLEANMGR.EXE
or by clicking the "Disk Cleanup" button on a drive's Properties dialog
in Explorer. The Properties dialog can be accessed by right-clicking on a drive
in Explorer and selecting "Properties" from the context menu or by
clicking on a drive in Explorer and selecting File then Properties.
- When you don't need it anymore simply unregister the server, and delete
the DLL file.
Conclusion
When I first registered my component and ran the cleanup manager (cleanmgr.exe),
thus launching my brand-new cleanup handler, I was amazed by the the size of
the intermediate files that Visual C++ has generated for its need (about 200
Mb).
Though this handler was intended to delete the files that visual C++ has generated, it can also be used for
other application temporary files or other purpose.
It has been tested only on windows XP, please tell me it work on your
machine. If you found this application of help, let me know at blackhorus@caramail.com
Begin programming in pascal some 8 years ago, then to assembly and C, after seeing that pascal is out of fashion. play a little with Delphi and C++ Builder, to see that was enough.
A little mess with other technologies, HTML, CGI, DHTML, PHP.