www.LinuxHowtos.org

XkbChangeTypesOfKey

Section: XKB FUNCTIONS (3)
Updated: libX11 1.6.4
Index Return to Main Contents

NAME

XkbChangeTypesOfKey - Change the number of groups and the types bound to a key

SYNOPSIS

Status XkbChangeTypesOfKey (XkbDescPtr xkb, int key, int n_groups, unsigned int groups, int *new_types_in, XkbMapChangesPtr p_changes);

ARGUMENTS

- xkb: keyboard description to be changed
- key: keycode for key of interest
- n_groups: new number of groups for key
- groups: mask indicating groups to change
- new_types_in: indices for new groups specified in groups
- p_changes: notes changes made to xkb

DESCRIPTION

XkbChangeTypesOfKey reallocates the symbols and actions bound to the key, if necessary, and initializes any new symbols or actions to NoSymbol or NoAction, as appropriate. If the p_changes parameter is not NULL, XkbChangeTypesOfKey adds the XkbKeySymsMask to the changes field of p_changes and modifies the first_key_sym and num_key_syms fields of p_changes to include the key that was changed. See STRUCTURE for more information on the XkbMapChangesPtr structure. If successful, XkbChangeTypesOfKey returns Success.

The n_groups parameter specifies the new number of groups for the key. The groups parameter is a mask specifying the groups for which new types are supplied and is a bitwise inclusive OR of the following masks: XkbGroup1Mask, XkbGroup2Mask, XkbGroup3Mask, and XkbGroup4Mask.

The new_types_in parameter is an integer array of length n_groups. Each entry represents the type to use for the associated group and is an index into xkb->map->types. The new_types_in array is indexed by group index; if n_groups is four and groups only has Group1Mask and Group3Mask set, new_types_in looks like this:


    new_types_in[0] = type for Group1
    new_types_in[1] = ignored
    new_types_in[2] = type for Group3
    new_types_in[3] = ignored

For convenience, Xkb provides the following constants to use as indices to the groups:

Table 1 Group Index Constants

Constant Name	Value

XkbGroup1Index	0
XkbGroup2Index	1
XkbGroup3Index	2
XkbGroup4Index	3

If the Xkb extension has not been properly initialized, XkbChangeTypesOfKey returns BadAccess. If the xkb parameter it not valid (that is, it is NULL or it does not contain a valid client map), XkbChangeTypesOfKey returns BadMatch. If the key is not a valid keycode, n_groups is greater than XkbNumKbdGroups, or the groups mask does not contain any of the valid group mask bits, XkbChangeTypesOfKey returns BadValue. If it is necessary to resize the key symbols or key actions arrays and any allocation errors occur, XkbChangeTypesOfKey returns BadAlloc.

STRUCTURES

Use the XkbMapChangesRec structure to identify and track partial modifications to the mapping components and to reduce the amount of traffic between the server and clients.


typedef struct _XkbMapChanges {
    unsigned short   changed;            /* identifies valid components in 
structure */
    KeyCode          min_key_code;       /* lowest numbered keycode for device 
*/
    KeyCode          max_key_code;       /* highest numbered keycode for device 
*/
    unsigned char    first_type;         /* index of first key type modified */
    unsigned char    num_types;          /* # types modified */
    KeyCode          first_key_sym;      /* first key whose key_sym_map changed 
*/
    unsigned char    num_key_syms;       /* # key_sym_map entries changed */
    KeyCode          first_key_act;      /* first key whose key_acts entry 
changed */
    unsigned char    num_key_acts;       /* # key_acts entries changed */
    KeyCode          first_key_behavior; /* first key whose behaviors changed */
    unsigned char    num_key_behaviors;  /* # behaviors entries changed */
    KeyCode          first_key_explicit; /* first key whose explicit entry 
changed */
    unsigned char    num_key_explicit;   /* # explicit entries changed */
    KeyCode          first_modmap_key;   /* first key whose modmap entry changed 
*/
    unsigned char    num_modmap_keys;    /* # modmap entries changed */
    KeyCode          first_vmodmap_key;  /* first key whose vmodmap changed */
    unsigned char    num_vmodmap_keys;   /* # vmodmap entries changed */
    unsigned char    pad1;               /* reserved */
    unsigned short   vmods;              /* mask indicating which vmods changed 
*/
} XkbMapChangesRec,*XkbMapChangesPtr;

DIAGNOSTICS

BadAccess: The Xkb extension has not been properly initialized
BadAlloc: Unable to allocate storage
BadMatch: A compatible version of Xkb was not available in the server or an argument has correct type and range, but is otherwise invalid
BadValue: An argument is out of range