NAME
XkbVirtualModsToReal - Determines the mapping of virtual modifiers to
core X protocol modifiers
SYNOPSIS
Bool XkbVirtualModsToReal (XkbDescPtr xkb, unsigned int virtual_mask,
unsigned int *mask_rtrn);
ARGUMENTS
- xkb keyboard description for input device
- virtual_mask
virtual modifier mask to translate
- mask_rtrn
backfilled with real modifiers
DESCRIPTION
Xkb maintains a virtual modifier mapping, which lists the virtual
modifiers associated with, or bound to, each key. The real modifiers
bound to a virtual modifier always include all of the modifiers bound
to any of the keys that specify that virtual modifier in their virtual
modifier mapping. The server.vmodmap array indicates which virtual
modifiers are bound to each key; each entry is a bitmask for the
virtual modifier bits. The server.vmodmap array is indexed by keycode.
The vmodmap and vmods members of the server map are the "master"
virtual modifier definitions. Xkb automatically propagates any changes
to these fields to all other fields that use virtual modifier mappings.
For example, if Mod3 is bound to the Num_Lock key by the core protocol
modifier mapping, and the NumLock virtual modifier is bound to they
Num_Lock key by the virtual modifier mapping, Mod3 is added to the set
of modifiers associated with NumLock.
The virtual modifier mapping is normally updated whenever actions are
automatically applied to symbols and few applications should need to
change the virtual modifier mapping explicitly.
Use XkbGetMap to get the virtual modifiers from the server or use
XkbGetVirtualMods to update a local copy of the virtual modifiers
bindings from the server. To set the binding of a virtual modifier to a
real modifier, use XkbGetVirtualMods
If the keyboard description defined by xkb includes bindings for
virtual modifiers, XkbVirtualModsToReal uses those bindings to
determine the set of real modifiers that correspond to the set of
virtual modifiers specified in virtual_mask. The virtual_mask
parameter is a mask specifying the virtual modifiers to translate; the
i-th bit (0 relative) of the mask represents the i-th virtual modifier.
If mask_rtrn is non-NULL, XkbVirtualModsToReal backfills it with the
resulting real modifier mask. If the keyboard description in xkb does
not include virtual modifier bindings, XkbVirtualModsToReal returns
False; otherwise, it returns True.
RETURN VALUES
True The XkbVirtualModsToReal function returns True if the
keyboard description in xkb does include virtual
modifier bindings.
False The XkbVirtualModsToReal function returns False if the
keyboard description in xkb does not include virtual
modifier bindings.
SEE ALSO
XkbGetMap(3), XkbGetVirtualMods(3)
NOTES
It is possible for a local (client-side) keyboard description (the xkb
parameter) to not contain any virtual modifier information (simply
because the client has not requested it) while the server’s
corresponding definition may contain virtual modifier information.