IABSD.fr/xenocara/lib/libX11/specs/XKB/ch12.xml

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• Author : matthieu
  Date : 2011-05-30 19:19:29
  Hash : 857c658f
  Message : Update to libx11 1.4.2. Tested by ajacoutot@, jasper@ krw@, landry@, shadchin@ on various architectures. Bump major.

• lib/libX11/specs/XKB/ch12.xml

• <chapter id='interpreting_key_events'>
  <title>Interpreting Key Events</title>
  
  <para>
  Xkb provides functions to help developers interpret key events without having
  to directly interpret Xkb data structures. Xkb also modifies the behavior of
  several core X library functions.
  </para>
  
  <sect1 id='effects_of_xkb_on_the_core_x_library'>
  <title>Effects of Xkb on the Core X Library</title>
  
  <para>
  When support for Xkb is built into the X library, the <emphasis>
  XOpenDisplay</emphasis>
   function looks for a compatible version of Xkb on the server. If it finds a
  compatible version, it initializes the extension and enables <emphasis>
  implicit support</emphasis>
   for Xkb in a number of X library functions. This makes it possible for clients
  to take advantage of nearly all Xkb features without having to be rewritten or
  even recompiled, if they are built with shared libraries. This implicit support
  is invisible to most clients, but it can have side effects, so the extension
  includes ways to control or disable it.
  </para>
  
  
  <sect2 id='effects_of_xkb_on_event_state'>
  <title>Effects of Xkb on Event State</title>
  
  <para>
  Because <emphasis>
  XOpenDisplay</emphasis>
   initializes Xkb, some events contain an Xkb description of the keyboard state
  instead of that normally used by the core protocol. See section 17.1.1 for more
  information about the differences between Xkb keyboard state and that reported
  by the core protocol.
  </para>
  
  
  </sect2>
  <sect2 id='effects_of_xkb_on_mappingnotify_events'>
  <title>Effects of Xkb on MappingNotify Events</title>
  
  <para>
  When Xkb is missing or disabled, the X library tracks changes to the keyboard
  mapping using <emphasis>
  MappingNotify</emphasis>
   events. Whenever the keyboard mapping is changed, the server sends all clients
  a <emphasis>
  MappingNotify</emphasis>
   event to report the change. When a client receives a <emphasis>
  MappingNotify</emphasis>
   event, it is supposed to call <emphasis>
  XRefreshKeyboardMapping</emphasis>
   to update the keyboard description used internally by the X library.
  </para>
  
  
  <para>
  The X Keyboard Extension uses <emphasis>
  XkbMapNotify</emphasis>
   and <emphasis>
  XkbNewKeyboardNotify</emphasis>
   events to track changes to the keyboard mapping. When an Xkb-aware client
  receives either event, it should call <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
   to update the keyboard description used internally by the X library. To avoid
  duplicate events, the X server does not send core protocol <emphasis>
  MappingNotify</emphasis>
   events to a client that has selected for <emphasis>
  XkbMapNotify</emphasis>
   events.
  </para>
  
  
  <para>
  The implicit support for Xkb selects for <emphasis>
  XkbMapNotify</emphasis>
   events. This means that clients that do not explicitly use Xkb but that are
  using a version of the X library that has implicit support for Xkb do not
  receive <emphasis>
  MappingNotify</emphasis>
   events over the wire. Clients that were not written with Xkb in mind do not
  recognize or properly handle the new Xkb events, so the implicit support
  converts them to <emphasis>
  MappingNotify</emphasis>
   events that report approximately the same information, unless the client has
  explicitly selected for the Xkb version of the event.
  </para>
  
  
  <para>
  An Xkb-capable X server does not send events from keys that fall outside the
  legal range of keycodes expected by that client. Once the server sends a client
  an <emphasis>
  XkbNewKeyboardNotify</emphasis>
   event, it reports events from all keys because it assumes that any client that
  has receieved an <emphasis>
  XkbNewKeyboardNotify</emphasis>
   event expects key events from the new range of keycodes. The implicit support
  for Xkb asks for <emphasis>
  XkbNewKeyboardNotify</emphasis>
   events, so the range of keycodes reported to the client might vary without the
  client’s knowledge. Most clients don’t really care about the range of legal
  keycodes, but some clients maintain information about each key and might have
  problems with events that come from unexpected keys. Such clients can set the
  <emphasis>
  XkbLC_IgnoreNewKeyboards</emphasis>
   library control (see section 11.3.1) to prevent the implicit support from
  requesting notification of changes to the legal range of keycodes.
  </para>
  
  
  </sect2>
  <sect2 id='x_library_functions_affected_by_xkb'>
  <title>X Library Functions Affected by Xkb</title>
  
  <para>
  The following X library functions are modified by Xkb:
  </para>
  
  <para><programlisting>
       <emphasis>XKeycodeToKeysym</emphasis>
       <emphasis>XKeysymToKeycode</emphasis>
       <emphasis>XLookupKeysym</emphasis>
       <emphasis>XLookupString</emphasis>
       <emphasis>XRefreshKeyboardMapping</emphasis>
       <emphasis>XRebindKeysym</emphasis>
  </programlisting></para>
  
  <para>
  The implicit support for Xkb replaces a number of X library functions with
  versions that understand and use the X Keyboard Extension. In most cases, the
  semantics of the new versions are identical to those of the old, but there are
  occasional visible differences. This section lists all of the functions that
  are affected and the differences in behavior, if any, that are visible to
  clients.
  </para>
  
  
  <para>
  The <emphasis>
  XKeycodeToKeysym</emphasis>
   function reports the keysym associated with a particular index for a single
  key. The index specifies a column of symbols in the core keyboard mapping (that
  is, as reported by the core protocol <emphasis>
  GetKeyboardMapping</emphasis>
   request). The order of the symbols in the core mapping does not necessarily
  correspond to the order of the symbols used by Xkb; section 17.1.3 describes
  the differences.
  </para>
  
  
  <para>
  The <emphasis>
  XKeysymToKeycode</emphasis>
   function reports a keycode to which a particular keysym is bound. When Xkb is
  missing or disabled, this function looks in each column of the core keyboard
  mapping in turn and returns the lowest numbered key that matches in the lowest
  numbered group. When Xkb is present, this function uses the Xkb ordering for
  symbols instead.
  </para>
  
  
  <para>
  The <emphasis>
  XLookupKeysym</emphasis>
   function reports the symbol in a specific column of the key associated with an
  event. Whether or not Xkb is present, the column specifies an index into the
  core symbol mapping.
  </para>
  
  
  <para>
  The <emphasis>
  XLookupString</emphasis>
   function reports the symbol and string associated with a key event, taking
  into account the keycode and keyboard state as reported in the event. When Xkb
  is disabled or missing, <emphasis>
  XLookupString</emphasis>
   uses the rules specified by the core protocol and reports only ISO Latin-1
  characters. When Xkb is present, <emphasis>
  XLookupString</emphasis>
   uses the explicit keyboard group, key types, and rules specified by Xkb. When
  Xkb is present, <emphasis>
  XLookupString</emphasis>
   is allowed, but not required, to return strings in character sets other than
  ISO Latin-1, depending on the current locale. If any key bindings are defined,
  <emphasis>
  XLookupString</emphasis>
   does not use any consumed modifiers (see sections 11.1.2 and 15.2) to
  determine matching bindings.
  </para>
  
  
  <para>
  The <emphasis>
  XRefreshKeyboardMapping</emphasis>
   function updates the X library’s internal representation of the keyboard to
  reflect changes reported via <emphasis>
  MappingNotify</emphasis>
   events. When Xkb is missing or disabled, this function reloads the entire
  modifier map or keyboard mapping. When Xkb is present, the implicit Xkb support
  keeps track of the changed components reported by each <emphasis>
  XkbMapNotify</emphasis>
   event and updates only those pieces of the keyboard description that have
  changed. If the implicit support has not noted any keyboard mapping changes,
  <emphasis>
  XRefreshKeyboardMapping</emphasis>
   updates the entire keyboard description.
  </para>
  
  
  <para>
  The <emphasis>
  XRebindKeysym</emphasis>
   function associates a string with a keysym and a set of modifiers. Xkb does
  not directly change this function, but it does affect the way that the state
  reported in the event is compared to the state specified to <emphasis>
  XRebindKeysym</emphasis>
  . When Xkb is missing or disabled, <emphasis>
  XLookupString</emphasis>
   returns the specified string if the modifiers in the event exactly match the
  modifiers from this call. When Xkb is present, any modifiers used to determine
  the keysym are consumed and are not used to look up the string.
  </para>
  
  
  </sect2>
  </sect1>
  <sect1 id='xkb_event_and_keymap_functions'>
  <title>Xkb Event and Keymap Functions</title>
  
  <para>
  To find the keysym bound to a particular key at a specified group and shift
  level, use <emphasis>XkbKeycodeToKeysym</emphasis>.
  </para>
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  KeySym <emphasis>
  XkbKeycodeToKeysym</emphasis>
  (<emphasis>
  dpy, kc, group, level</emphasis>
  )
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  Display *            dpy;            /* connection to X server */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeyCode            kc;            /* key of interest */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int            group;            /* group of interest */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int            level;            /* shift level of interest */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XkbKeycodeToKeysym</emphasis>
   returns the keysym bound to a particular group and shift level for a
  particular key on the core keyboard. If <emphasis>
  kc</emphasis>
   is not a legal keycode for the core keyboard, or if <emphasis>
  group</emphasis>
   or <emphasis>
  level</emphasis>
   are out of range for the specified key, <emphasis>
  XkbKeycodeToKeysym</emphasis>
   returns <emphasis>
  NoSymbol</emphasis>
  .
  </para>
  
  
  <para>
  To find the set of modifiers bound to a particular keysym on the core keyboard,
  use <emphasis>
  XkbKeysymToModifiers</emphasis>
  .
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  unsigned<emphasis>
   </emphasis>
  int <emphasis>
  XkbKeysymToModifiers</emphasis>
  (<emphasis>
  dpy</emphasis>
  ,<emphasis>
   ks</emphasis>
  )
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  Display *<emphasis>
              dpy</emphasis>
  ;            /* connection to X server */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeySym <emphasis>
              ks</emphasis>
  ;            /* keysym of interest */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XkbKeysymToModifiers</emphasis>
   finds the set of modifiers currently bound to the keysym <emphasis>
  ks</emphasis>
   on the core keyboard. The value returned is the mask of modifiers bound to the
  keysym <emphasis>
  ks</emphasis>
  . If no modifiers are bound to the keysym, <emphasis>
  XkbKeysymToModifiers</emphasis>
   returns zero; otherwise, it returns the inclusive OR of zero or more of the
  following: <emphasis>
  ShiftMask</emphasis>
  , <emphasis>
  ControlMask</emphasis>
  , <emphasis>
  LockMask</emphasis>
  , <emphasis>
  Mod1Mask</emphasis>
  , <emphasis>
  Mod2Mask</emphasis>
  , <emphasis>
  Mod3Mask</emphasis>
  , <emphasis>
  Mod4Mask,</emphasis>
   and <emphasis>
  Mod5Mask</emphasis>
  .
  </para>
  
  
  <para>
  Use <emphasis>
  XkbLookupKeySym</emphasis>
   to find the symbol associated with a key for a particular state.
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  Bool <emphasis>
  XkbLookupKeySym</emphasis>
  (<emphasis>
  dpy</emphasis>
  ,<emphasis>
   key</emphasis>
  ,<emphasis>
   state</emphasis>
  ,<emphasis>
   mods_rtrn</emphasis>
  ,<emphasis>
   sym_rtrn</emphasis>
  )
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  Display * <emphasis>
              dpy</emphasis>
  ;            /* connection to X server */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeyCode <emphasis>
              key</emphasis>
  ;            /* key for which symbols are to be found */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int <emphasis>
              state</emphasis>
  ;            /* state for which symbol should be found */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int * <emphasis>
              mods_rtrn</emphasis>
  ;            /* backfilled with unconsumed modifiers */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeySym *<emphasis>
              sym_rtrn</emphasis>
  ;            /* backfilled with symbol associated with key + state */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XkbLookupKeySym</emphasis>
   is the equivalent of the core <emphasis>
  XLookupKeySym</emphasis>
   function. For the core keyboard, given a keycode <emphasis>
  key</emphasis>
   and an Xkb state <emphasis>
  state</emphasis>
  , <emphasis>
  XkbLookupKeySym</emphasis>
   returns the symbol associated with the key  in <emphasis>
  sym_rtrn</emphasis>
   and the list of modifiers that should still be applied in <emphasis>
  mods_rtrn</emphasis>
  . The <emphasis>
  state</emphasis>
   parameter is the state from a <emphasis>
  KeyPress</emphasis>
   or <emphasis>
  KeyRelease</emphasis>
   event. <emphasis>
  XkbLookupKeySym</emphasis>
   returns <emphasis>
  True</emphasis>
   if it succeeds.
  </para>
  
  
  <para>
  Use <emphasis>
  XkbLookupKeyBinding</emphasis>
   to find the string bound to a key by <emphasis>
  XRebindKeySym</emphasis>
  . <emphasis>
  XkbLookupKeyBinding</emphasis>
   is the equivalent of the core <emphasis>
  XLookupString</emphasis>
   function.
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  int <emphasis>
  XkbLookupKeyBinding</emphasis>
  (<emphasis>
  dpy</emphasis>
  ,<emphasis>
   sym</emphasis>
  ,<emphasis>
   state</emphasis>
  ,<emphasis>
   buf</emphasis>
  ,<emphasis>
   nbytes</emphasis>
  ,<emphasis>
   extra_rtrn</emphasis>
  )
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  Display * <emphasis>
              dpy</emphasis>
  ;            /* connection to server */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeySym<emphasis>
              sym</emphasis>
  ;            /* symbol to be looked up */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int            <emphasis>
  state</emphasis>
  ;            /* state for which string is to be looked up */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  char * <emphasis>
              buf</emphasis>
  ;            /* buffer into which returned string is written */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  int <emphasis>
              nbytes</emphasis>
  ;            /* size of buffer in bytes */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  int * <emphasis>
              extra_rtrn</emphasis>
  ;            /* backfilled with number bytes overflow */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XRebindKeysym</emphasis>
   binds an ASCII string to a specified keysym, so that the string and keysym are
  returned when the key is pressed and a specified list of modifiers are also
  being held down. <emphasis>
  XkbLookupKeyBinding</emphasis>
   returns in <emphasis>
  buf</emphasis>
   the string associated with the keysym <emphasis>
  sym</emphasis>
   and modifier state <emphasis>
  state</emphasis>
  . <emphasis>
  buf</emphasis>
   is <emphasis>
  NULL</emphasis>
   terminated unless there’s an overflow. If the string returned is larger than
  <emphasis>
  nbytes</emphasis>
  , a count of bytes that does not fit into the buffer is returned in extra_rtrn.
  <emphasis>
  XkbTranslateKeySym</emphasis>
   returns the number of bytes that it placed into <emphasis>
  buf</emphasis>
  .
  </para>
  
  
  <para>
  To find the string and symbol associated with a keysym for a given keyboard
  state, use <emphasis>
  XkbTranslateKeySym</emphasis>
  .
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  int <emphasis>
  XkbTranslateKeySym</emphasis>
  (<emphasis>
  dpy</emphasis>
  ,<emphasis>
   sym_inout</emphasis>
  ,<emphasis>
   mods</emphasis>
  ,<emphasis>
   buf</emphasis>
  ,<emphasis>
   nbytes</emphasis>
  , <emphasis>
  extra_rtrn</emphasis>
  )
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  Display * <emphasis>
              dpy</emphasis>
  ;            /* connection to X server */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeySym * <emphasis>
              sym_inout</emphasis>
  ;            /* symbol to be translated; result of translation */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int <emphasis>
              mods</emphasis>
  ;            /* modifiers to apply to <emphasis>
  sym_inout</emphasis>
   */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  char * <emphasis>
              buf</emphasis>
  ;            /* buffer into which returned string is written */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  int <emphasis>
              nbytes</emphasis>
  ;            /* size of buffer in bytes */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  int *<emphasis>
              extra_rtrn</emphasis>
  ;            /* number of bytes overflow*/
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XkbTranslateKeySym</emphasis>
   applies the transformations specified in <emphasis>
  mods</emphasis>
   to the symbol specified by <emphasis>
  sym_inout</emphasis>
  . It returns in <emphasis>
  buf</emphasis>
   the string, if any, associated with the keysym for the current locale. If the
  transformations in <emphasis>
  mods</emphasis>
   changes the keysym, <emphasis>
  sym_inout</emphasis>
   is updated accordingly. If the string returned is larger than <emphasis>
  nbytes</emphasis>
  , a count of bytes that does not fit into the buffer is returned in extra_rtrn.
  <emphasis>
  XkbTranslateKeySym</emphasis>
   returns the number of bytes it placed into <emphasis>
  buf</emphasis>
  .
  </para>
  
  
  <para>
  To update the keyboard description that is internal to the X library, use
  <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
  .
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  Status <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
  (<emphasis>
  event)</emphasis>
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  XkbMapNotifyEvent * <emphasis>
              event</emphasis>
  ;            /* event initiating remapping */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
   is the Xkb equivalent of the core <emphasis>
  XRefreshKeyboardMapping</emphasis>
   function. It requests that the X server send the current key mapping
  information to this client. A client usually invokes <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
   after receiving an <emphasis>
  XkbMapNotify</emphasis>
   event. <emphasis>
  XkbRefreshKeyboardMapping</emphasis>
   returns <emphasis>
  Success</emphasis>
   if it succeeds and <emphasis>
  BadMatch</emphasis>
   if the event is not an Xkb event.
  </para>
  
  
  <para>
  The <emphasis>
  XkbMapNotify</emphasis>
   event can be generated when some client calls <emphasis>
  XkbSetMap</emphasis>
  , <emphasis>
  XkbChangeMap</emphasis>
  , <emphasis>
  XkbGetKeyboardByName</emphasis>
  , or any of the standard X library functions that change the keyboard mapping
  or modifier mapping.
  </para>
  
  
  <para>
  To translate a keycode to a key symbol and modifiers, use <emphasis>
  XkbTranslateKeyCode</emphasis>
  .
  </para>
  
  
  <informaltable frame='none'>
  <tgroup cols='1'>
  <colspec colsep='0'/>
  <tbody>
    <row rowsep='0'>
      <entry role='functiondecl'>
  Booll <emphasis>
  XkbTranslateKeyCode</emphasis>
  (<emphasis>
  xkb, key, mods, mods_rtrn, keysym_rtrn)</emphasis>
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  XkbDescPtr            <emphasis>
  xkb</emphasis>
  ;            /* keyboard description to use for translation */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeyCode            <emphasis>
  key</emphasis>
  ;            /* keycode to translate */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int            <emphasis>
  mods</emphasis>
  ;            /* modifiers to apply when translating <emphasis>
  key</emphasis>
   */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  unsigned int *            <emphasis>
  mods_rtrn</emphasis>
  ;            /* backfilled with unconsumed modifiers */
      </entry>
    </row>
    <row rowsep='0'>
      <entry role='functionargdecl'>
  KeySym *            <emphasis>
  keysym_rtrn</emphasis>
  ;            /* keysym resulting from translation */
      </entry>
  </row>
  </tbody>
  </tgroup>
  </informaltable>
  
  <para>
  <emphasis>
  mods_rtrn</emphasis>
   is backfilled with the modifiers consumed by the translation process.
  <emphasis>
  mods</emphasis>
   is a bitwise inclusive OR of the legal modifier masks: <emphasis>
  ShiftMask</emphasis>
  , <emphasis>
  LockMask</emphasis>
  , <emphasis>
  ControlMask</emphasis>
  , <emphasis>
  Mod1Mask</emphasis>
  , <emphasis>
  Mod2Mask</emphasis>
  , <emphasis>
  Mod3Mask</emphasis>
  , <emphasis>
  Mod4Mask</emphasis>
  , <emphasis>
  Mod5Mask</emphasis>
  .The <emphasis>
  AlwaysConsumeShiftAndLock</emphasis>
   library control (see section 11.1.3), if enabled, causes <emphasis>
  XkbTranslateKeyCode</emphasis>
   to consume shift and lock.<emphasis>
   XkbTranslateKeyCode</emphasis>
   returns <emphasis>
  True</emphasis>
   if the translation resulted in a keysym, and <emphasis>
  False</emphasis>
   if it resulted in <emphasis>
  NoSymbol</emphasis>
  .
  </para>
  </sect1>
  </chapter>