bug#57604: [ef]grep usage -> POSIXLY_CORRECT?

[Bruce Dubbs]

On 9/11/22 14:45, Sam wrote:
> > On 11 Sep 2022, at 21:41, Jim Meyering <jim@meyering.net> wrote:
> >
> > On Thu, Sep 8, 2022 at 4:01 PM Karl Berry <karl@freefriends.org> wrote:
> > > Hi Jim,
> > >
> > >     Some must care about portability,
> > >
> > > Certainly agreed. Even I do, sometimes :). But that does not mean
> > > everyone needs to, in every situation.  As I said, I fail to understand
> > > the benefit of making the warning unconditional.
> > >
> > > So far as I can see, it's also against GNU principles, as I wrote,
> > > though evidently you don't agree.
> > >
> > >     and these warnings help them do a better job.
> > >
> > > When people want extreme POSIX compliance, they should set
> > > POSIXLY_CORRECT. That's what it's there for, and that's when I think the
> > > warnings should be issued, as I said at the beginning.
> > >
> > > But since Paul rejected that, ok, a different variable that lets us turn
> > > them off (GREPWARNINGS=efgrepok or whatever) would at least provide some
> > > palliation. I don't understand why you two are opposed to this simple
> > > remediation.
> > >
> > >     As Gary mentioned above, it's easy to disable them.
> > >
> > > Obviously it is trivial to edit the scripts or have a different version
> > > in PATH for my own machine(s).  But those are no substitute for having a
> > > supported way to use the distributed [ef]grep without warnings.
> > >
> > >     I would argue that it is even more important to retain these
> > >     stray-backslash warnings, because they tend to highlight real bugs.
> > >
> > > "tend" being the key word there. But anyway, I see your point, and won't
> > > argue that one further, since the efgrep warnings are what's causing me
> > > the agony. -k
> >
> > Hi Karl,
> >
> > It would help if you could point to some malfunction.
>
> We've hit one malfunction in Gentoo: https://bugs.gentoo.org/868384.
>
> A program was using libgcrypt-config via CMake and ended up
> failing because of the warnings.
>
> (The program's usage is IMO ill-advised and it should use pkg-config,
> but that's beside the point).
>
> > Consider the alternative.
> >
> > Should we release a new version of grep that provides a documented way
> > (say a configure-time option) to disable a warning about a
> > long-deprecated feature so you don't have to manually tweak the
> > four-line fgrep and egrep scripts? AFAIK, these new warnings cause no
> > malfunction.
> >
> > Wouldn't it be better to fix the roots of the problem rather than
> > piling another kludge on top to disable the annoying warnings? Think
> > about the next steps: when more and more distros cease to distribute
> > the egrep and fgrep crutches, what will people do? Eventually, we'll
> > all break the habit, at least in scripts. If you want to use it in
> > personal scripts or on the command line, create your wrapper script or
> > alias/function.
>
> I honestly think at this point, it'd be better to just deem them GNU
> extensions.

After discussing this a bit in the LFS community, we tend to agree.  For us in the 
'from source' community, editing two short scripts is pretty trivial, but it really
shouldn't be needed.

  -- Bruce