bookmark_bordersecure wipe

#apt-get install secure-delete

It will provide the following tools for secure wiping:

/usr/bin/srm
/usr/bin/sfill
/usr/bin/sswap
/usr/bin/sdmem

srm – secure remove (secure_deletion toolkit)

$srm file_name
$srm -r folder_name


There is already another tool “shred” comes with “coreutils” package in Debian:
coreutils – GNU core utilities

/usr/bin/shred

shred – overwrite a file to hide its contents, and optionally delete it

$shred file_name

sfill  –  secure free disk and inode space wiper (secure_deletion toolkit)

#sfill /mount_point/

sswap – secure swap wiper (secure_deletion toolkit)

Turn off swap first :

 #swapoff /dev/sdaX
or
#swapoff -a  //to turn off all swap

Now run sswap:

#sswap /dev/sdaX 

sdmem – secure memory wiper (secure_deletion toolkit)

There is some limitation of these tools.
Please use manual pages of individual package for details information.