Bug#7150: Distinguishing between left and right Alt keys on NextStep/OSX.

* lisp/cus-start.el (all): ns-right-alternate-modifier is new.

* lisp/term/ns-win.el (ns-right-alternate-modifier): New defvar.
(ns-right-option-modifier): New alias for ns-right-alternate-modifier.
(mac-right-option-modifier): New alias for ns-right-option-modifier.

* src/nsterm.m (Qleft): Declare.
(ns_right_alternate_modifier): New variable
(NSRightAlternateKeyMask): New define.
(EV_MODIFIERS): Parse NSRightAlternateKeyMask if
ns_right_alternate_modifier isn't Qleft.
(keyDown): If ns_right_alternate_modifier isn't Qleft, use it
as emacs modifier for NSRightAlternateKeyMask.
(syms_of_nsterm): DEFVAR_LISP ns-right-alternate-modifier.

1 files changed, 3 insertions, 0 deletions

diff --git a/lisp/term/ns-win.el b/lisp/term/ns-win.el
index a53d0346d94..b9177b2b432 100644
--- a/lisp/term/ns-win.el
+++ b/lisp/term/ns-win.el
@@ -66,6 +66,7 @@
 ;; nsterm.m
 (defvar ns-version-string)
 (defvar ns-alternate-modifier)
+(defvar ns-right-alternate-modifier)
 
 ;;;; Command line argument handling.
 
@@ -286,6 +287,7 @@ The properties returned may include `top', `left', `height', and `width'."
 (defvaralias 'mac-command-modifier 'ns-command-modifier)
 (defvaralias 'mac-control-modifier 'ns-control-modifier)
 (defvaralias 'mac-option-modifier 'ns-option-modifier)
+(defvaralias 'mac-right-option-modifier 'ns-right-option-modifier)
 (defvaralias 'mac-function-modifier 'ns-function-modifier)
 (declare-function ns-do-applescript "nsfns.m" (script))
 (defalias 'do-applescript 'ns-do-applescript)
@@ -817,6 +819,7 @@ unless the current buffer is a scratch buffer."
 
 ;; You say tomAYto, I say tomAHto..
 (defvaralias 'ns-option-modifier 'ns-alternate-modifier)
+(defvaralias 'ns-right-option-modifier 'ns-right-alternate-modifier)
 
 (defun ns-do-hide-emacs ()
   (interactive)