Tag Archives: Bash

Generating secure passphrases on the command line

The following snippet should work on every system that has coreutils.

$ shuf /usr/share/dict/words --repeat --random-source /dev/random -n 5

You can swap /usr/share/dict/words with any good wordlist, like EFF’s or Arnold Reinhold’s Diceware list.

You can also add it for ease of use to your ~/.bash_aliases

alias passphrase="shuf ~/dotfiles/misc/diceware8k.txt --repeat --random-source /dev/random -n"

And then you could easily use it in bash:

$ passphrase 5
notch
kane
to
drag
cater

Temporary Disabling Bash History

Say that you’ve got to pass some password as command line argument to something. It would probably be a bad idea to store it in your ~/.bash_history, but clearing the file isn’t desired either. So you need to temporary disable the command history for the current session. You can do it by unsetting the HISTFILE environment variable.

unset HISTFILE

The result is that while the session is active you can access the history as usual, but it won’t be saved to the disk. History for other sessions, will behave as usual.

Improved FTP Backup for WordPress

This script backups both the database and files of a WordPress blog into a remote FTP server (while keeping a local copy). It’s an update of my WordPress Backup to FTP script. The main changes are auto-detecting database settings and better support for caching plugins (specifically WP-Cache). The new version makes it easier to backup multiple WordPress blogs to the same FTP server.
Continue reading