Re: Can the exit status of the code block in @(...) be obtained from outside the @() structure?

[Hongyi Zhao]

On Sat, Jan 22, 2022 at 9:40 AM Hongyi Zhao <hongyi.zhao@gmail.com> wrote:
>
> On Sat, Jan 22, 2022 at 9:28 AM Hongyi Zhao <hongyi.zhao@gmail.com> wrote:
> >
> > On Sat, Jan 22, 2022 at 3:05 AM Paul Smith <psmith@gnu.org> wrote:
> > > [...]
> > > As mentioned before, the entire script must be contained in a single
> > > logical line if you want the same shell to interpret it all.  So you'll
> > > have to add "\" to combine all these into a single logical line:
> >
> > Thank you for your above knowledgeable and thorough analysis. Got it.
> >
> > >   define download_and_unpack
> > >     package='$(1)' ; \
> > >     package_URL='$(2)' ; \
> > >     package_directory='$(3)' ; \
> > >     package_code='$(4)' ; \
> > >     package_archive=../archive/`echo "$(package)" | sed 
> > > 's/.*\///;s/.*=//'` ; \
> > >     ( \
> > >     if ! gzip -t $(package_archive) > /dev/null 2>&1 ; then \
> >
> > I tried with your above trick, but noticed that the variable
> > package_archive can be expanded correctly:
> >
> > $ make -j44 w90
> > [...]
> > package='wannier90-3.1.0';
> > package_URL='https://codeload.github.com/wannier-developers/wannier90/tar.gz/v3.1.0';
> > package_directory='W90'; package_code='wannier90';
> > package_archive=../archive/`echo "" | sed 's/.*\///;s/.*=//'`;
> >
> > As you can see, the following command:
> >
> > package_archive=../archive/`echo "$(package)" | sed 's/.*\///;s/.*=//'`; \
> >
> > will be passed as:
> >
> > package_archive=../archive/`echo "" | sed 's/.*\///;s/.*=//'`;
> >
> > As you can see, the expansion of "$(package)" has been lost. Based on
> > tries, it seems the following form fixes this problem:
> >
> > package_archive=../archive/`echo "$$(package)" | sed 's/.*\///;s/.*=//'`; \
>
> Sorry, it should be written as follows:
>
> package_archive=../archive/`echo "$${package}" | sed 's/.*\///;s/.*=//'`; \
>
> And then refer to these variables using the following formats:
>
> $${package}
> $${package_URL}
> $${package_directory}
> $${package_code}
> $${package_archive}

Even so, it seems still rather ugly and cumbersome. As suggested by
Sam Kendall <sckendall2@gmail.com>, I really want to work out a pure
shell script based solution as the drop-in replacement.

Regards,
HZ