---
name: "XkbNoteIndicatorChanges"
section: "3"
platform: "linux"
package: "libx11-doc"
version: "2:1.8.4-2+deb12u2"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/XkbNoteIndicatorChanges"
---

# XkbNoteIndicatorChanges(3)

Notes the changes in a changes structure

## NAME

XkbNoteIndicatorChanges - Notes the changes in a changes structure

## SYNOPSIS

**void XkbNoteIndicatorChanges** **(XkbIndicatorChangesPtr** *old***,** **XkbIndicatorNotifyEvent \****new***,** **unsigned int** *wanted***);**

## ARGUMENTS

- *old*

  XkbIndicatorChanges structure to be updated

- *new*

  event from which changes are to be copied

- *wanted*

  which changes are to be noted

## DESCRIPTION

Whenever an indicator changes state, the server sends XkbIndicatorStateNotify events to all  interested clients. Similarly, whenever an indicator's map changes, the server sends  XkbIndicatorMapNotify events to all interested clients.

To receive XkbIndicatorStateNotify events, use  *XkbSelectEvents* with both the  *bits\_to\_change* and  *values\_for\_bits* parameters containing XkbIndicatorStateNotifyMask. To receive XkbIndicatorMapNotify events,  use  *XkbSelectEvents* with XkbIndicatorMapNotifyMask.

To receive events for only specific indicators, use  *XkbSelectEventDetails.* Set the  *event\_type* parameter to XkbIndicatorStateNotify or XkbIndicatorMapNotify, and set both the *bits\_to\_change* and  *values\_for\_bits* detail parameters to a mask where each bit specifies one indicator, turning on those bits that  specify the indicators for which you want to receive events.

The  *changed* parameter is a mask that is the bitwise inclusive OR of the indicators that have changed. If  the event is of type XkbIndicatorMapNotify,  *changed* reports the maps that changed. If the event is of type XkbIndicatorStateNotify,  *changed* reports the indicators that have changed state.  *state* is a mask that specifies the current state of all indicators, whether they have changed or  not, for both XkbIndicatorStateNotify and IndicatorMapNotify events.

When your client application receives either a XkbIndicatorStateNotify event or  XkbIndicatorMapNotify event, you can note the changes in a changes structure by calling *XkbNoteIndicatorChanges.*

The  *wanted* parameter is the bitwise inclusive OR of XkbIndicatorMapMask and  XkbIndicatorStateMask.  *XkbNoteIndicatorChanges* copies any changes reported in  *new* and specified in  *wanted* into the changes record specified by  *old.*

## STRUCTURES

Both types of indicator events use the same structure:

```
typedef struct _XkbIndicatorNotify {
  int            type;       /* Xkb extension base event code */
  unsigned long  serial;     /* X server serial number for event */
  Bool           send_event; /* True => synthetically generated */
  Display *      display;    /* server connection where event generated */
  Time           time;       /* server time when event generated */
  int            xkb_type;   /* specifies state or map notify */
  int            device;     /* Xkb device ID, will not be XkbUseCoreKbd */
  unsigned int   changed;    /* mask of indicators with new state or map */
  unsigned int   state;      /* current state of all indicators */
} XkbIndicatorNotifyEvent;
```

*xkb\_type* is either XkbIndicatorStateNotify or XkbIndicatorMapNotify, depending on whether the event is  a kbIndicatorStateNotify event or kbIndicatorMapNotify event.

## SEE ALSO

**XkbIndicatorMapMask**(3), **XkbIndicatorStateMask**(3), [**XkbSelectEventDetails**(3)](/XkbSelectEventDetails/3.md), [**XkbSelectEvents**(3)](/XkbSelectEvents/3.md)