[src/trunk]: src/usr.bin/window use offsetof() instead of some strange local ...

[mrg <mrg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f98f60386611
branches:  trunk
changeset: 766430:f98f60386611
user:      mrg <mrg%NetBSD.org@localhost>
date:      Wed Jun 22 06:22:48 2011 +0000

description:
use offsetof() instead of some strange local hack.

diffstat:

 usr.bin/window/window_string.h |  4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diffs (18 lines):

diff -r 4c7845225936 -r f98f60386611 usr.bin/window/window_string.h
--- a/usr.bin/window/window_string.h    Wed Jun 22 05:50:47 2011 +0000
+++ b/usr.bin/window/window_string.h    Wed Jun 22 06:22:48 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: window_string.h,v 1.8 2009/04/14 08:50:06 lukem Exp $  */
+/*     $NetBSD: window_string.h,v 1.9 2011/06/22 06:22:48 mrg Exp $    */
 
 /*
  * Copyright (c) 1983, 1993
@@ -62,7 +62,7 @@
 
 EXTERN struct string str_head;
 
-#define str_offset ((unsigned)str_head.s_data - (unsigned)&str_head)
+#define str_offset offsetof(struct string, s_data)
 #define str_stos(s) ((struct string *)((unsigned)(s) - str_offset))
 
 char   *str_alloc(size_t);