Re: [PATCH] maint.mk: fix VPATH issues

[Jim Meyering]

Akim Demaille wrote:
> Hi Jim!
>
> Maybe my question below was not visible.  I'd like to know
> what option you prefer.
...
>>> I like to avoid using pwd, because it can fail (admittedly unlikely, 
>>> but...).
>>> Did you consider just doing the "cd" and those four commands in a sub-shell,
>>> instead?
>>
>> Actually I lost trust in subshells :(  It's too hard to have a
>> shell script fail from a subshell (calling your "die" does not
>> suffice).
>>
>> #! /bin/sh
>>
>> set -e
>> (
>>  set -e
>>  exit 42
>>  echo end
>> )
>> echo "done ($?)"
>>
>> $ sh /tmp/subsh.sh
>> done (42)
>>
>> I would have expected the outer set -e to be effective.  But
>> I can check $? at the end if you prefer, and go with ().
>
> Right above.  Should I stick to pwd (my preference), or do
> you prefer a sub-shell?

Hi Akim,

You're welcome to use pwd.
set -e is in effect, so pwd failure will be caught, and changing
the working directory in a script like this is not a problem.

>> (Also, in some of my scripts I issue GNU Make-like "entering"
>> messages for sake of Emacs, so using "cd $cwd" became more
>> natural to me than relying on subshells)
>>
>>>> +srcdir=$(pwd)
>>>> +cd "$builddir"
>>>> +  ./config.status --recheck
>>>> +  ./config.status
>>>> +  make
>>>> +  make web-manual
>>>> +cd "$srcdir"
>>>> +set +e
>>>> +
>>>> +tmp=$(mktemp -d web-doc-update.XXXXXX) || exit 1
>>>> ( cd $tmp \
>>>>    && cvs -d address@hidden:/webcvs/$pkg co $pkg )
>>>> -rsync -avP doc/manual/ $tmp/$pkg/manual
>>>> +rsync -avP "$builddir"/doc/manual/ $tmp/$pkg/manual
>>