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

On Mac OS X, getdelim() first became available with Xcode 4.1[1], which was released the same day as OS X 10.7 "Lion", so assume getdelim() availability from 10.7 onward. (As of this writing, OS X is at 10.10 "Yosemite".)

According to Wikipedia[2], 4.1 was also available for download by paying developers on OS X 10.6 "Snow Leopard", so it's possible that some 10.6 machines may have getdelim(). However, as strbuf's use of getdelim() is purely an optimization, let's be conservative and assume 10.6 and earlier lack getdelim().

[1]: Or, possibly with Xcode 4.0, but that version is no longer
     available for download, or not available to non-paying developers,
     so testing is not possible.

[2]: http://en.wikipedia.org/wiki/Xcode

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
---

Tested on OS X 10.10.3 "Yosemite" with Xcode 6.3.2 and OS X 10.5.8 "Leopard" with Xcode 3.1.

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).

 config.mak.uname | 3 +++
 1 file changed, 3 insertions(+)