In this resource regular monospaced font is used for generic code, monospaced bolt font for the reserved keywords of Bash and monospaced italic font for parts that must be modified in order to match the actual needs.

As defined in EBNF, square brackets [ and ] in regular monospaced font contain an optional part and curled brackets { and } in regular monospaced font an optional part that may be repeated. (The Extended Backus–Naur Form has been standardised in ISO/IEC 14977:1996, yet this is shamefully behind a paywall.)


We use uppercase for constants, as well as for values that are set during the initialisation, and lowercase for variables and function names: ${THIS_IS_A_CONSTANT} and ${that_is_a_variable}. In addition, we always use curled brackets for the value of variables and constants, also when they are optional because separated from the surrounding code.