Remove files

[David Epstein]

Does MacPorts have a version of rm that does secure removal of files  
(that is, scribbling over the disk so that info cannot be recovered)?  
I want this for files about my bank dealings---I'm not referring to  
files that come from MacPorts downloads.

Does MacPorts have a version of rm that (unlike Unix, but like Mac Os  
X) is undoable?

Metaquestion: how would one research this issue before writing in to  
this list? I tried but failed.

Thanks from David.Epstein at warwick.ac.uk