GNU fcrypt not touch your real hard disks. Instead GNU fcrypt use a normal file and write encrypted data on it.
You can create partition's
Using fcrypt -c <some file name>
In this case <some file name> not need exists.
GNU fcrypt can create it.
You can use -z instead -c.
If you need hide some data, in the case
the attacker force you to reveal the password.
In GNU/Linux after created. You can activate the partition
using fcrypt -a <file name>.
Once activated, the partitions are accessed in
/dev/fcrypt[some letter] (eg. /dev/fcrypta).
Encryption is automatic and transparent, so you can access
as if you were accessing a volume that is not encrypted.
You can create a file system using mkfs and then
mount it using mount(eg.
mkfs.ext4 /dev/fcrypta and
mount /dev/fcrypta /mnt).
To deactivate GNU fcrypt. Make sure that no program is
using: /dev/fcrypt(It is not the same
/dev/fcrypt_info). If /dev/fcrypt is
mounted, umount it(eg. umount /dev/fcrypta).
Then simply interrupt GNU fcrypt. Once stopped GNU
fcrypt will not process any more requests. Programs
that try to write/read data from /dev/fcrypt
will get a Input/Output error. New opened
programs can no longer open /dev/fcrypt,
these programs will get the error:
Device or resource busy.
If you want to finalize GNU fcrypt, I recommend
you to not use kill -9 or killall -9.
Instead you can use the simply kill or
killall(without the -9).
Because, when correctly finalized, GNU fcrypt,
will write the remaining data to disk and
delete all it's allocated data from memory.