History is only enabled for interactive shells, not scripts. So in a script,
history -c won't do much good. If you just want to empty your user's bash history during boot, as
/tmp is emptied during boot, just truncate or delete
echo "cleaning the history"
This uses shell redirection without a command. It makes the shell just open the file for writing (truncating it if it already exists), then close it without writing anything to it (since there's no command to write anything to it).
On a side note, don't use absolute paths to commands in scripts. E.g. use
update: Or if you don't want to save bash history at all, you could put something like
HISTFILE=/dev/null in your