Re: Makefile: uses rsync(1), could this be optional?

[Steffen Nurpmeso <steffen@sdaoden.eu>]

Guten Tag.

Masahiro Yamada wrote in
 <CAK7LNAQOm8NYiTDQnd0P-UsGa7GurffQiWQgGh0Cze4wLmDmgA@mail.gmail.com>:
 |On Fri, Jan 21, 2022 at 4:31 AM Steffen Nurpmeso <steffen@sdaoden.eu> \
 |wrote:
 |> I sent this to linux-kernel@vger.kernel.org on the 15th, which
 |> seems to be legacy.  Just in case someone is wondering about the
 |> resend.
 |
 |I did not see your previous post.
 |What is bad about using rsync?

Oh really nothing, but this Linux distribution (CRUX) recreates
Linux headers before the GNU LibC is build, and this is the only
dependency of rsync around.  And, unless i am mistaken, the other
code path is more expensive but otherwise functionally equivalent?

 |> As a not-yet-tested low-quality Makefile suggestion, with modern
 |> GNU tools and find(1)'s -printf, wouldn't the following code work
 |> out gracefully in practice?  (Not subscribed.)
 |>
 |> Thanks for Linux!
 |>
 |> --- Makefile.orig       2022-01-15 19:33:59.337393371 +0100
 |> +++ Makefile    2022-01-15 19:34:07.447393217 +0100
 |> @@ -1260,8 +1288,17 @@ export INSTALL_HDR_PATH = $(objtree)/usr
 |>  quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
 |>        cmd_headers_install = \
 |>         mkdir -p $(INSTALL_HDR_PATH); \
 |> -       rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
 |> -       usr/include $(INSTALL_HDR_PATH)
 |> +       if command -v rsync; then \
 |> +               rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
 |> \
 |> +               usr/include $(INSTALL_HDR_PATH);\
 |> +       else \
 |> +               cd usr;\
 |> +               find include/ -type f -name '*.h' -printf '%f %h\n' |\
 |> +               while read f d; do \
 |> +                       mkdir -p $(INSTALL_HDR_PATH)/$$d;\
 |> +                       cp -P $$d/$$f $(INSTALL_HDR_PATH)/$$d/$$f;\
 |> +               done;\
 |> +       fi
 |>
 |>  PHONY += headers_install
 |>  headers_install: headers

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)