41.2 Using vi to Encrypt Single Files
The disadvantage of using encrypted partitions is that while
the partition is mounted, at least root can access the data. To prevent this, vi can
be used in encrypted mode.
vi -x filename
to edit a new file. vi prompts you to set a password, after which
it encrypts the content of the file. Whenever you access this
file, vi requests the correct password.
For even more security, you can place the encrypted text file
in an encrypted partition. This is recommended because the
encryption used in vi is not very strong.