This page collects a set of bash scripting idioms and tools for easy reference.
With -e (errexit), bash exits immediately if an unchecked command exits with a nonzero value.
A checked command is part of a while, until, if, elif, or an expression with && or ||.
Everything else is unchecked.
For a pipeline, only the last command is considered. Adding "or no-op", || :,
ensures a command is safe, e.g., do-something | grep 'may_not_match' || :.
NB. Calling a bash function in a checked context effectively disables -e for all commands in the function.
Use the optional shellcheck, check-set-e-suppressed, to alert on this.
