File cleaning

I am looking for a function that cleans thoroughly the junkfiles as in the .bat files from Fred Langa. Cleanall.bat and Cleanupexpert.bat.

Thanks for your good work.

My question is perhaps a little more clear if I ask this way.

Is it not possible to clean files more thorougly at the DOS level ?

I was impressed from the result when using the batch files.

For example Spybot is scanning files this way when it installs for the first time.