Re: About Section 7.2.2 "Utilities in Makefiles" of the GCS

[Ralf Wildenhues]

Hello,

* Vincent Lefevre wrote on Wed, Mar 19, 2008 at 04:19:21PM CET:
> I have a few comments about Section 7.2.2 "Utilities in Makefiles" of
> the GNU Coding Standards.

FWIW, this was spawned by
<http://thread.gmane.org/gmane.comp.sysutils.autoconf.bugs/5961>.

> * "Stick to the generally supported options for these programs."
> is vague and misleading. People might think that POSIX options are
> OK despite the given example ("mkdir -p", where -p is specified by
> POSIX). I even saw developers using non-POSIX options! Could this
> paragraph be more specific?

Maybe it should link to the Autoconf manual section about portable shell
scripts.  But mentioning to generally not assume more than POSIX except
in a few well-known-portable cases is probably a good idea.

FWIW, mkdir -p is listed because it is not parallel build-safe on some
non-free systems.

> Also, concerning the "test" utility, the following should probably
> be added:
> 
>   With the "test" utility, avoid ambiguity. Even though the behavior
>   is specified by POSIX, many implementations behave differently.
>   For instance, to test whether the length of a string is zero or
>   not, use an explicit "-z" or "-n".

This could be elegantly solved with above: a link to
<http://www.gnu.org/software/autoconf/manual/html_node/Portable-Shell.html>

which covers this and many more issues.

Cheers,
Ralf