I agree with almost everything in this guide, but it has a couple of recommendations that create new problems (while solving others): The nullglob option ('sho

I agree with almost everything in this guide, but it has a couple of recommendations that create new problems (while solving others): The nullglob option ('shopt -s nullglob') makes things like 'for f in .txt' work right when there are no matching files, but make other commands like 'grep somepattern .txt' change their behavior in ways that can cause serious trouble. grep (and many other commands), given no files as input, will read from standard input (up to the EOF); if it's running interactively and input hasn't been redirected, this causes the script to hang for no discernible reason. If input has been redirected, it steals input that was presumably meant to be read by some other command. In my opinion, the problems this causes are more serious than what it solves. The errexit option ('set -e' or 'shopt -s errexit') can both fail to exit when you expect/want it to (several such situations are described in the guide) and also exit when you don't expect/want it to. The guide mentions suppressing unexpected exits with '|| true', but it's not always obvious when this is needed, and it's not even consistent between versions of bash. There's a good parable about this (and some examples) at http://mywiki.wooledge.org/BashFAQ/105 http://mywiki.wooledge.org/BashFAQ/105 I really don't like trying to predict and work around unpredictable features like this; I'd much rather deal with explicit error handling, like 'commandThatMightFail || { echo "Aaaargh" >&2; exit 1; }'