[PATCH xserver] configure: use backticks rather than $() for commands

[Alan Coopersmith]

Dan Nicholson wrote:
> On Thu, Jan 7, 2010 at 4:16 PM, Matt Turner <mattst88 at gmail.com> wrote:
>> On Thu, Jan 7, 2010 at 3:06 PM, Gaetan Nadon <memsize at videotron.ca> wrote:
>>> This patch to xserver configure.ac is to increase code portability to
>>> non POSIX system by using backticks rather than $() for command
>>> substitution for BUILD_DATE and BUILD_TIME.
>>>
>> What kind of systems would these be?
> 
> Older Solaris was definitely the common case where it would come up.

Yes, /bin/sh on Solaris releases up to and including Solaris 10 and
Solaris Express is a pre-POSIX bourne shell that only supports `` not $().
There are POSIX shells available, but then builders always have to remember
to run /bin/bash ./configure or /bin/ksh ./configure instead of just ./configure.

OpenSolaris and future Solaris releases make /bin/sh be ksh93 instead, so
won't have this limitation, but it will be a long time before Solaris 10
and older variants die out in the wild.

-- 
	-Alan Coopersmith-           alan.coopersmith at sun.com
	 Sun Microsystems, Inc. - X Window System Engineering