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In-Reply-To: <20221207162208.2200189-1-alexandr.lobakin@intel.com>
From:   Masahiro Yamada <masahiroy@kernel.org>
Date:   Sat, 10 Dec 2022 23:10:12 +0900
Message-ID: <CAK7LNAQbGaXDRzeByOcJhMX4y-ShA6Qtpcqhr4gNZ5t8vX-PPw@mail.gmail.com>
Subject: Re: [PATCH v3 3/5] kbuild: add read-file macro
To:     Alexander Lobakin <alexandr.lobakin@intel.com>
Cc:     linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
        Nicolas Schier <nicolas@fjasle.eu>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>
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On Thu, Dec 8, 2022 at 1:25 AM Alexander Lobakin
<alexandr.lobakin@intel.com> wrote:
>
> From: Alexander Lobakin <alexandr.lobakin@intel.com>
> Date: Wed, 7 Dec 2022 16:40:44 +0100
>
> > From: Masahiro Yamada <masahiroy@kernel.org>
> > Date: Sun, 27 Nov 2022 07:56:22 +0900
> >
> > > Since GNU Make 4.2, $(file ...) supports the read operater '<', which
> > > is useful to read a file without forking any process. No warning is
> > > shown even if the input file is missing.
>
> [...]
>
> > Great stuff. Used it in my upcoming series to simplify things, works
> > as expected.
> >
> > sed-syms = $(subst $(space),\|,$(foreach file,$(sym-files-y),$(call read-file,$(file))))
> >
> > The only thing that came to my mind while I was implementing the
> > oneliner above: maybe add ability to read multiple files? For now,
> > I used a foreach, could it be somehow incorporated into read-file
> > already?
>
> Oh, nevermind. This one also works:
>
> sed-syms = $(subst $(space),\|,$(call read-file,$(sym-files-y)))
>
> So I believe read-file works for an arbitrary number of files.


Really?


In my understanding, $(call read-file, foo bar) reads a single file "foo bar".
(a space in the file name).


>
> >
> > Besides that:
> >
> > Reviewed-and-tested-by: Alexander Lobakin <alexandr.lobakin@intel.com>
>
> [...]
>
> > > --
> > > 2.34.1
> >
> > Thanks,
> > Olek
>
> Thanks!
> Olek


-- 
Best Regards
Masahiro Yamada