Five Useful Bash Aliases

Here are five bash aliases that I find useful.

List contents of current directory, sorted by size

alias 'dus=du -sckx * | sort -nr'

Here is a breakdown of the command.

• du – command estimates file system usage
• -s – creates a total for each argument
• -c – creates a grand total
• -k – sets the block size to kilobytes. Using -m would set it to megabytes
• -x – skips directories on other file systems

The output of the du -sckx * command is then piped to sort -nr.

• sort – sorts lines
• -n – does a numerical sort
• -r – reverses the result, so it is in descending order

Show all currently assigned IPv4 IP addresses

alias inet='ifconfig | grep inet | grep -v inet6'

Here is a breakdown of the command.

• ifconfig – lists the current network interface configuration
• | grep inet – returns only the lines with inet
• | grep -v inet6 – eliminate those lines with inet6, i.e., IPv6

Depending on your OS you may need to use ip a instead of ifconfig.

List directory contents sorted by modification time

alias latr='ls -latr'

Here is a breakdown of the command.

• ls – lists directory contents
• -l – use the long format
• -a – do not ignore hidden files
• -t – sort by modification time, newest first
• -r – reverse the sort order

The mnemonic I use for this alias is “later”.

Look up a word’s definition

alias 'define=curl dict://dict.org/define:"$@"'

Here is a breakdown of the comment.

• curl – transfers a URL, in this case dict://dict/org/define
• "$@" – the search term provided

Make a password

alias makepass='openssl rand -base64 15'

Here is a breakdown of the command.

• openssl – runs the openssl command line tool
• rand – generates pseudo-random bytes
• -base64 – use base64
• 15 – make the resulting password 15 characters long