2019-08-14 09:28:22 -0700, Kaz Kylheku (Coreutils):
[...]
> According to POSIX, echo doesn't take options. It is specified
> that "Implementations shall not support any options."
> (We have options, though, so things are complicated.)
[...]
The POSIX specification of "echo" is going to change in
On 2019-08-14 05:01, Harald Dunkel wrote:
Hi folks,
I just learned by accident that
var="-n"
/bin/echo -- $var
actually prints
-- -n
Shouldn't it be just
-n
?
According to POSIX, echo doesn't take options. It is specified
that "Implementations shall not
echo is defunct by definition.
The preferred way is
printf %s\\n "data"
which is much more stable against such "attacks"!
Also it is far more stable to be used for multiline output:
printf %s\\n "line 1" line\ 2 'line 3' "line 5 and
line 6"
and no, it shouldn't. echo should not be used but
On 8/14/19 7:01 AM, Harald Dunkel wrote:
> Hi folks,
>
> I just learned by accident that
>
> var="-n"
> /bin/echo -- $var
>
> actually prints
>
> -- -n
Correct. This is the POSIX-mandated behavior.
>
> Shouldn't it be just
>
> -n
No, because 'echo' is one of the
Hi folks,
I just learned by accident that
var="-n"
/bin/echo -- $var
actually prints
-- -n
Shouldn't it be just
-n
?
Other tools in coreutils use '--' to indicate "stop parsing for
command line flags", e.g. touch, ls and rm:
% /bin/touch -- -l
