A set of bit-flags to indicate the state of modifier keys and mouse buttons in various event types. Typical modifier keys are Shift, Control, Meta, Super, Hyper, Alt, Compose, Apple, CapsLock or ShiftLock keys.

Like the X Window System, GDK supports 8 modifier keys and 5 mouse buttons.

GDK recognizes which of the Meta, Super or Hyper keys are mapped to Mod2 - Mod5, and indicates this by setting the :super-mask, :hyper-mask or :meta-mask mask in the state field of key events.

Note that GDK may add internal values to events which include reserved values such as GDK_MODIFIER_RESERVED_13_MASK. Your code should preserve and ignore them. You can use the :modifier-mask mask to remove all reserved values.

Also note that the GDK X backend interprets button press events for button 4-7 as scroll events, so the :button4-mask and :button5-mask masks will never be set.

(define-g-flags "GdkModifierType" gdk-modifier-type
  (:export t
   :type-initializer "gdk_modifier_type_get_type")
  (:shift-mask   #.(ash 1 0))
  (:lock-mask    #.(ash 1 1))
  (:control-mask #.(ash 1 2))
  (:mod1-mask    #.(ash 1 3))
  (:mod2-mask    #.(ash 1 4))
  (:mod3-mask    #.(ash 1 5))
  (:mod4-mask    #.(ash 1 6))
  (:mod5-mask    #.(ash 1 7))
  (:button1-mask #.(ash 1 8))
  (:button2-mask #.(ash 1 9))
  (:button3-mask #.(ash 1 10))
  (:button4-mask #.(ash 1 11))
  (:button5-mask #.(ash 1 12))
  (:super-mask   #.(ash 1 26))
  (:hyper-mask   #.(ash 1 27))
  (:meta-mask    #.(ash 1 28))
  (:release-mask #.(ash 1 30))
  (:modifier-mask #x5c001fff))  

:shift-mask

The Shift key.

:lock-mask

A Lock key, depending on the modifier mapping of the X server this may either be the CapsLock or ShiftLock key.

:control-mask

The Control key.

:mod1-mask

The fourth modifier key. It depends on the modifier mapping of the X server which key is interpreted as this modifier, but normally it is the Alt key.

:mod2-mask

The fifth modifier key. It depends on the modifier mapping of the X server which key is interpreted as this modifier.

:mod3-mask

The sixth modifier key. It depends on the modifier mapping of the X server which key is interpreted as this modifier.

:mod4-mask

The seventh modifier key. It depends on the modifier mapping of the X server which key is interpreted as this modifier.

:mod5-mask

The eighth modifier key. It depends on the modifier mapping of the X server which key is interpreted as this modifier.

:button1-mask

The first mouse button.

:button2-mask

The second mouse button.

:button3-mask

The third mouse button.

:button4-mask

The fourth mouse button.

:button5-mask

The fifth mouse button.

:super-mask

The Super modifier.

:hyper-mask

The Hyper modifier.

:meta-mask

The Meta modifier.

:release-mask

Not used in GDK itself. GTK uses it to differentiate between (keyval, modifiers) pairs from key press and release events.

:modifier-mask

A mask covering all modifier types.