Re: shell utility printf enhancement request

[Philip Guenther <guenther@xxxxxxxxx>]

On Wed, Aug 5, 2009 at 4:29 PM, Wayne Pollock<pollock@acm.org> wrote:
> The printf utility was designed to portably replace
> the incompatible versions of echo in use.  It does
> this admirably with one potential problem.  Printf
> is specified to take no arguments.  This is fine with
> me except I have noticed Bash shell has a built-in
> version of printf that does take arguments.
>
> I would like to see the official standard allow
> implementation-defined arguments, marked by an
> end of argument ``--''.  that is,
>
>   printf -- '%s\n' "Hello world"
>
> should be allowed and portable.  Indeed, I'd like
> to see ``--'' be allowed for all utilities that
> can take any arguments or options at all.

AFAICT, that *is* allowed and portable.  I.e., that command is
required to output "Hello world" followed by a newline.

Comparing the 'OPTIONS' section of the echo and printf command
descriptions in the standard, along with section 1.4 of this:
        http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap01.html

may be enlightening.


Philip Guenther