--passphrase-file file
Read the passphrase from file file. Only the first line will be read from file file. This can only be used if only one passphrase is supplied. Obviously, a
passphrase stored in a file is of questionable security if other users can read this file. Don't use this option if you can avoid it.
Note that since Version 2.0 this passphrase is only used if the option --batch has also been given. Since Version 2.1 the --pinentry-mode also needs to be set to
loopback.
--passphrase string
Use string as the passphrase. This can only be used if only one passphrase is supplied. Obviously, this is of very questionable security on a multi-user system.
Don't use this option if you can avoid it.