Re: Problem with positional output

2016-11-14 12:28:10 -0800, Jim Hill:
> I think Stephane's method is best, though I don't see the need for the
> noglob here, I think
> 
>     (IFS=\|; set -- $RETVAL; printf %s\\n "$3")

No, the set -o noglob is needed here.

Using a variable unquoted in Bourne-like shells except zsh is
the split+glob operator.

Try with:

RETVAL='*|?|[a-z]'

For instance.

See also

https://unix.stackexchange.com/questions/171346/security-implications-of-forgetting-to-quote-a-variable-in-bash-posix-shells

More generally, when leaving a variable or other expansion
unquoted, you need to consider $IFS and the status of the noglob
option.

> As an alternative if your data doesn't contain newlines, awk is
> specialized for this,
> 
>    awk -F\| '{print $3}' <<<"$RETVAL"
> 
> will do the same job.

Again, that retrieves the 3rd field of every line of $RETVAL, not
the 3rd field in $RETVAL.

If you're going to use that zsh <<< operator (though it's now
also supported by recent versions of ksh93 and bash), you could
as well use ${"${(@s:|:)REVAL}"[3]}.

s:|: splits on |
@ preserves empty elements within quotes

-- 
Stephane