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Comment by belter | Hacker News Reader

Maybe the discussion should start at: Can you even do anything safely in Bash? - https://mywiki.wooledge.org/BashPitfalls

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That's an excellent resource.

Luckily, most commonly encountered scripting issues are with whitespace in filenames/variables and running a script through shellcheck will catch most (all?) of those problems.

It's amazing how edge cases can make a simple command such as 'echo' break. (Top tip - use printf instead of echo)

echo has long been unreliable. Even the built-in echo in the shells were unreliable in SunOS, because the shell would look at the binaries in your PATH and try to figure out whether to emulate the BSD vs SysV (IIRC) version of echo and then change what echo would do. So much for writing a single script (with echo) that would work for all your users on the same host.

This is why you'll see code like this: echo 'prompt: ' | tr -d '\012'

No other simple mechanism was portable at the time. Seriously portability-minded coders still use that line, because although the issue is finally dead in linux+bash (i.e. /bin/echo is enough like bash's builtin) - it's likely still broken in other Unixen out there.

echo is unreliable; I agree. Instead, I use "paranoid" printf with leading double dash:

    prinf -- "fmt str here..." "$carefully" "$quoted" "$args"

printf -- "fmt str here..." "${carefully}" "${quoted}" "${args}"

What is the difference?

In this example: None

That list seems to be loosely sorted by obscurity. I knew the first 29! What's your highscore?

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