2017-05-19 20:41:12 +0000, Thorsten Glaser:
> Stephane Chazelas dixit:
>
> >In mksh, printf is not built-in which doesn't help. In all but
>
> But in mksh, you just do this to quote:
>
> local foo
> set -A foo
> for x in "$@"; do
> foo+=("${x@Q}")
> done
>
> Or, probably faster:
>
> local foo nfoos=0
> set -A foo
> for x in "$@"; do
> foo[nfoos++]=${x@Q}
> done
>
> ${var @ something} is mksh’s extension to expansion.
> Currently, Q (shell-quote) and # (hash) are defined.
[...]
True, but here the question was about using the POSIX sh API.
Note that zsh, bash and ksh93 have equivalent operators (printf
%q in zsh/bash/ksh93, ${(q)var}, ${(qq)var}, ${(qqq)var},
%${(qqqq)var} for various forms of quoting in zsh, or $var:q).
But here, mksh's ${var@Q} doesn't work for answering the
original question: store "$@" into a scalar variable to restore
afterwards as ${empty@Q} expands to an empty string instead of
''.
Also note that it doesn't quote U+00A0 nor 0xA0 nor any of the
other non-ASCII characters, and resorts to $'...' when the
variable contains ASCII control characters, which makes the
result unsuitable to pass to POSIX shells for evaluation.
That's also the case for the printf %q of bash/ksh93/zsh. Only
zsh's ${(qq)var} (amongst the ones mentioned above) could be
used here.
--
Stephane
