Don't you have 'shred' from the command line?
Would this work?
system("shred insecure_file.dat -zu &")
Note the command detaches with &, so a slow
shred won't slow down your server's response.
Thanks for the note on '&'. I just checked and shred is available, but I didn't know about the detach option. I've been looking for something asynchronous to avoid a negative impact to the visitor experience. I was also hoping for something that was more integral to the file system. Do you have any experience with srm? (http://srm.sourceforge.net/ )
And note that you cannot guarantee security like this;
you must start with your server's physical security.
All kinds of artifacts from the information will remain
on your hard drive.
This is my first 'dive' into this and, yeah, it's pretty complicated. Looks like I need to know, at a minimum, the type of devices in use, the setup of the devices wrt RAID, and the file system in use. I'm beginning to wonder if my goals are achievable on an VPS setup. Any experience / opinions much appreciated.