Mastering Bash

Keywords

A keyword is a reserved word that has a special meaning to the shell and is hardwired in it such as the builtins; but differing from the latter, the keywords are not full-blown commands, but parts of a command construct, and you can have a list of these by just typing this:

• compgen -k
• if
• then
• else
• elif
• fi
• case
• esac
• for
• select
• while
• until
• do
• done
• in
• function
• time
• {
• }
• !
• [[
• ]]

From the command line, but not from a script, the exclamation mark triggers the bash history.