Re: [PATCH 1/2] config.mak.uname: Darwin: define HAVE_GETDELIM for modern OS X releases

On Tue, Jun 02, 2015 at 02:18:57PM -0400, Eric Sunshine wrote:

The use of 'expr' in this new test is decidedly different from existing
instances which merely check if `uname -R` matches a particular single
digit and a period. If the new test took the same approach, it would
have to match either one digit (in a particular range) plus a period, or
two digits with the first being "1", plus a period. The resulting 'expr'
expression quickly becomes ugly and quite difficult to decipher. Hence,
the new test instead takes advantage of expr's relational operator '>='
to keep things simple and make the test easy to understand at a glance
("if version >= 11" where 11 is the Darwin major version number of OS X
10.7).

I think that is OK with respect to portability; we are already inside a
$(uname_S) check, so we know we are on some form of Mac OS. But...

+	ifeq ($(shell expr $(shell expr "$(uname_R)" : '\([0-9][0-9]*\)\.') '>=' 11),1)

Do you need to spawn two shells? It seems like:

  $(shell expr `expr "$(uname_R)" : '\([0-9][0-9]*\)'` '>=' 11),1)

should do the same thing.

-Peff