Erase the current shell history, cleans cache memory, dentries, inodes and swap.
$ bash -i sh_cleaner.sh
Or
$ ./sh_cleaner.sh
Note: The script if the script is run like the first option, it has to be using the interactive switch, this is so the script can read the $HISTFILE, which is not-present in an non-interactive shell (Like the one on a normal bash script).