17 Sep
2024
17 Sep
'24
7:54 a.m.
I think it was only Plan 9. The change was motivated by the
rc shell, which treated x=y anywhere on the command line (not just
at the beginning of a command) as a variable assignment.
(For a while I used Byron's rc. I was used to typing
echo ===============
to generate separator lines. rc threw a syntax error at me. :-)
Arnold
Rob Pike <robpike(a)gmail.com> wrote:
I don't remember whether late Research Unix had
-if, but Plan 9 certainly
did.
-rob
On Tue, Sep 17, 2024 at 10:06 AM segaloco via TUHS <tuhs(a)tuhs.org> wrote:
> On Monday, September 16th, 2024 at 4:24 PM, Larry McVoy <lm(a)mcvoy.com>
> wrote:
>
> > On Tue, Sep 17, 2024 at 09:16:17AM +1000, Dave Horsfall wrote:
> >
> > > On Mon, 16 Sep 2024, Lyndon Nerenberg (VE7TFX/VE6BBM) wrote:
> > >
> > > > Oh come on Rob, you should know that for anyone over the age of 50,
> the
> > > > moment you see 'dd' your brain automatically switches to
JCL mode.
> > >
> > > Indeed, but no "dd" I know has "-if" etc; is that a
Penguin thing?
> >
> >
> > Not a penguin thing on current xubuntu.
>
> Never seen that either, POSIX doesn't suggest any support for that either,
> with this in the RATIONALE section:
>
> ---QUOTE---
>
> The OPTIONS section is listed as "None" because there are no options
> recognized by historical dd utilities. Certainly, many of the operands
> could have been designed to use the Utility Syntax Guidelines, which would
> have resulted in the classic hyphenated option letters. In this version of
> this volume of POSIX.1-2024, dd retains its curious JCL-like syntax due to
> the large number of applications that depend on the historical
> implementation.
>
> ---END QUOTE---
>
> - Matt G.
>