Re: BSD m4 (was: more m4 underquotations)

[Eric Blake]

> > I DO know that in the
> > current source code of BSD m4, "changequote(,)" behaves
> > like "changequote" (ie. sets the quotes to ` and ') rather than
> > the GNU behavior of disabling quotes.
> 
> This sounds like a POSIX [1] violation of BSD m4.

Nope.  It was at my request that the Austin group agreed that
POSIX was ambiguous in this area, and that the next version
of POSIX will be worded as follows[1]:

The behavior is unspecified if there is a single argument
 or either argument is null.

[1]http://www.opengroup.org/austin/aardvark/latest/xcubug2.txt,
search for "Enhancement Request Number 112"

-- 
Eric Blake