1<chapter id='Key_Event_Processing_in_the_Server'> 2<title>Key Event Processing in the Server</title> 3 4<para> 5This section describes the steps involved in processing a key event within the 6server when XKB is present. Key events can be generated due to keyboard 7activity and passed to XKB by the DDX layer, or they can be synthesized by 8another extension, such as XTEST. 9</para> 10 11<sect1 id='Applying_Global_Controls'> 12<title>Applying Global Controls</title> 13 14<para> 15When the X Keyboard Extension receives a key event, it first checks the global 16key controls to decide whether to process the event immediately or at all. The 17global key controls which might affect the event, in descending order of 18priority, are: 19</para> 20 21<itemizedlist> 22<listitem> 23 <para>If a key is pressed while the <emphasis> 24BounceKeys</emphasis> 25 control is enabled, the extension generates the event only if the key is 26active. When a key is released, the server deactivates the key and starts a 27<emphasis> 28bounce keys timer</emphasis> 29 with an interval specified by the debounce delay. 30 </para> 31 <para> 32If the bounce keys timer expires or if some other key is pressed before the 33timer expires, the server reactivates the corresponding key and deactivates the 34timer. Neither expiration nor deactivation of a bounce keys timer causes an 35event.</para> 36</listitem> 37<listitem> 38 <para>If the <emphasis> 39SlowKeys</emphasis> 40 control is enabled, the extension sets a <emphasis> 41slow keys timer</emphasis> 42 with an interval specified by the slow keys delay, but does not process the 43key event immediately. The corresponding key release deactivates this timer. 44 </para> 45 <para> 46If the slow keys timer expires, the server generates a key press for the 47corresponding key, sends an <emphasis> 48XkbAccessXNotify</emphasis> 49 and deactivates the timer. 50 </para> 51</listitem> 52<listitem> 53 <para>The extension processes key press events normally whether or not the 54<emphasis> 55RepeatKeys</emphasis> 56 control is active, but if <emphasis> 57RepeatKeys</emphasis> 58 are enabled and per-key autorepeat is enabled for the event key, the extension 59processes key press events normally, but it also initiates an <emphasis> 60autorepeat timer</emphasis> 61 with an interval specified by the autorepeat delay. The corresponding key 62release deactivates the timer. 63 </para> 64 <para> 65If the autorepeat timer expires, the server generates a key release and a key 66press for the corresponding key and reschedules the timer according to the 67autorepeat interval. 68 </para> 69</listitem> 70</itemizedlist> 71 72<para> 73Key events are processed by each global control in turn: if the <emphasis> 74BounceKeys</emphasis> 75 control accepts a key event, <emphasis> 76SlowKeys</emphasis> 77 considers it. Once <emphasis> 78SlowKeys</emphasis> 79 allows or synthesizes an event, the <emphasis> 80RepeatKeys</emphasis> 81 control acts on it. 82</para> 83 84 85</sect1> 86<sect1 id='Key_Behavior'> 87<title>Key Behavior</title> 88 89<para> 90Once an event is accepted by all of the controls or generated by a timer, the 91server checks the per-key behavior of the corresponding key. This extension 92currently defines the following key behaviors: 93</para> 94 95<informaltable frame='topbot'> 96<?dbfo keep-together="always" ?> 97<tgroup cols='2' align='left' colsep='0' rowsep='0'> 98<colspec colname='c1' colwidth='1.0*'/> 99<colspec colname='c2' colwidth='3.0*'/> 100<thead> 101 <row rowsep='1'> 102 <entry>Behavior</entry> 103 <entry>Effect</entry> 104 </row> 105</thead> 106<tbody> 107 <row> 108 <entry><emphasis> 109KB_Default</emphasis> 110 </entry> 111 <entry>Press and release events are processed normally.</entry> 112 </row> 113 <row> 114 <entry><emphasis> 115KB_Lock</emphasis> 116 </entry> 117 <entry>If a key is logically up (i.e. the corresponding bit of the core key 118map is cleared) when it is pressed, the key press is processed normally and the 119corresponding release is ignored. If the key is logically down when pressed, 120the key press is ignored but the corresponding release is processed normally. 121</entry> 122 </row> 123 <row> 124 <entry> 125 <para> 126 <emphasis> 127KB_RadioGroup 128</emphasis> 129 </para> 130 <para> 131 flags: CARD8 132 </para> 133 <para> 134 index: CARD8 135 </para> 136 </entry> 137 <entry><para>If another member of the radio group specified by <emphasis> 138index</emphasis> 139 is logically down when a key is pressed, the server synthesizes a key release 140for the member that is logically down and then processes the new key press 141event normally. </para> 142<para> 143If the key itself is logically down when pressed, the key press event is 144ignored, but the processing of the corresponding key release depends on the 145value of the <emphasis> 146RGAllowNone</emphasis> 147 bit in <emphasis> 148flags</emphasis> 149. If it is set, the key release is processed normally; otherwise the key 150release is also ignored. 151</para> 152<para> 153All other key release events are ignored.</para> 154 </entry> 155 </row> 156 <row> 157 <entry> 158 <para> 159 <emphasis> 160KB_Overlay1 161</emphasis> 162 </para> 163 <para> 164 key: KEYCODE 165 </para> 166 </entry> 167 <entry>If the <emphasis> 168Overlay1</emphasis> 169 control is enabled, events from this key are reported as if they came from the 170key specified in <emphasis> 171key</emphasis> 172. Otherwise, press and release events are processed normally.</entry> 173 </row> 174 <row> 175 <entry> 176 <para> 177 <emphasis> 178KB_Overlay2 179</emphasis> 180 </para> 181 <para> 182 key: KEYCODE 183 </para> 184 </entry> 185 <entry>If the <emphasis> 186Overlay2</emphasis> 187 control is enabled, events from this key are reported as if they came from the 188key specified in <emphasis> 189key</emphasis> 190. Otherwise, press and release events are processed normally.</entry> 191 </row> 192</tbody> 193</tgroup> 194</informaltable> 195 196<para> 197The X server uses key behavior to determine whether to process or filter out 198any given key event; key behavior is independent of keyboard modifier or group 199state (each key has exactly one behavior. 200</para> 201 202<para> 203Key behaviors can be used to simulate any of these types of keys or to indicate 204an unmodifiable physical, electrical or software driver characteristic of a 205key. An optional <emphasis> 206permanent</emphasis> 207 flag can modify any of the supported behaviors and indicates that behavior 208describes an unalterable physical, electrical or software aspect of the 209keyboard. Permanent behaviors cannot be changed or set by the <emphasis> 210XkbSetMap</emphasis> 211 request. The <emphasis> 212permanent</emphasis> 213 flag indicates a characteristic of the underlying system that XKB cannot 214affect, so XKB treats all permanent behaviors as if they were <emphasis> 215KB_Default</emphasis> 216 and does not filter key events described in the table above. 217</para> 218 219 220</sect1> 221<sect1 id='Key_Actions'> 222<title>Key Actions</title> 223 224<para> 225Once the server has applied the global controls and per-key behavior and has 226decided to process a key event, it applies <emphasis> 227key actions</emphasis> 228 to determine the effects of the key on the internal state of the server. A key 229action consists of an operator and some optional data. XKB supports actions 230which: 231</para> 232 233<itemizedlist> 234<listitem> 235 <para>change base, latched or locked modifiers or group 236 </para> 237</listitem> 238<listitem> 239 <para>move the core pointer or simulate core pointer button events 240 </para> 241</listitem> 242<listitem> 243 <para>change most aspects of keyboard behavior 244 </para> 245</listitem> 246<listitem> 247 <para>terminate or suspend the server 248 </para> 249</listitem> 250<listitem> 251 <para>send a message to interested clients 252 </para> 253</listitem> 254<listitem> 255 <para>simulate events on other keys 256 </para> 257</listitem> 258</itemizedlist> 259 260<para> 261Each key has an optional list of actions. If present, this list parallels the 262list of symbols associated with the key (i.e. it has one action per symbol 263associated with the key). For key press events, the server looks up the action 264to be applied from this list using the key symbol mapping associated with the 265event key, just as a client looks up symbols as described in <link 266linkend='Determining_the_KeySym_Associated_with_a_Key_Event'>Determining the KeySym Associated with a 267Key Event</link>; if the event key does not have any actions, the server uses 268the <emphasis> 269SA_NoAction</emphasis> 270 event for that key regardless of modifier or group state. 271</para> 272 273 274<para> 275Key actions have essentially two halves; the effects on the server when the key 276is pressed and the effects when the key is released. The action applied for a 277key press event determines the further actions, if any, that are applied to the 278corresponding release event or to events that occur while the key is held down. 279Clients can change the actions associated with a key while the key is down 280without changing the action applied next time the key is released; subsequent 281press-release pairs will use the newly bound key action. 282</para> 283 284 285<para> 286Most actions directly change the state of the keyboard or server; some actions 287also modify other actions that occur simultaneously with them. Two actions 288occur simultaneously if the keys which invoke the actions are both logically 289down at the same time, regardless of the order in which they are pressed or 290delay between the activation of one and the other. 291</para> 292 293 294<para> 295Most actions which affect keyboard modifier state accept a modifier definition 296(see <link linkend='Virtual_Modifiers'>Virtual Modifiers</link>) 297named <emphasis> 298mods</emphasis> 299 and a boolean flag name <emphasis> 300useModMap</emphasis> 301 among their arguments. These two fields combine to specify the modifiers 302affected by the action as follows: If <emphasis> 303useModMap</emphasis> 304 is <emphasis> 305True</emphasis> 306, the action sets any modifiers bound by the modifier mapping to the key that 307initiated the action; otherwise, the action sets the modifiers specified by 308<emphasis> 309mods</emphasis> 310. For brevity in the text of the following definitions, we refer to this 311combination of <emphasis> 312useModMap</emphasis> 313 and <emphasis> 314mods</emphasis> 315 as the "action modifiers." 316</para> 317 318 319<para> 320The X Keyboard Extension supports the following actions: 321</para> 322 323<informaltable frame='topbot'> 324<?dbfo keep-together="auto" ?> 325<tgroup cols='2' align='left' colsep='0' rowsep='0'> 326<colspec colname='c1' colwidth='1.0*'/> 327<colspec colname='c2' colwidth='3.0*'/> 328<thead> 329 <row rowsep='1'> 330 <entry>Action</entry> 331 <entry>Effect</entry> 332 </row> 333</thead> 334<tbody> 335 <row> 336 <entry><emphasis>SA_NoAction</emphasis></entry> 337 <entry> 338 <itemizedlist> 339 <listitem> 340 <para> 341No direct effect, though <emphasis>SA_NoAction</emphasis> 342 events may change the effect of other server actions (see below). 343 </para> 344 </listitem> 345 </itemizedlist> 346 </entry> 347 </row> 348 <row> 349 <entry> 350 <para> 351 <emphasis>SA_SetMods</emphasis> 352 </para> 353 <para> 354 mods: MOD_DEF 355 </para> 356 <para> 357 useModMap: BOOL 358 </para> 359 <para> 360 clearLocks: BOOL 361 </para> 362 </entry> 363 <entry> 364 <itemizedlist> 365 <listitem> 366 <para> 367Key press adds any action modifiers to the keyboard’s base modifiers<emphasis>.</emphasis> 368 </para> 369 </listitem> 370 <listitem> 371 <para>Key release clears any action modifiers in the keyboard’s base 372modifiers, provided that no other key which affects the same modifiers is 373logically down. 374 </para> 375 </listitem> 376 <listitem> 377 <para>If no keys were operated simultaneously with this key and <emphasis> 378clearLocks</emphasis> 379 is set, release unlocks any action modifiers. 380 </para> 381 </listitem> 382 </itemizedlist> 383 </entry> 384 </row> 385 <row> 386 <entry> 387 <para> 388 <emphasis> 389SA_LatchMods 390</emphasis> 391 </para> 392 <para> 393 mods: MOD_DEF 394 </para> 395 <para> 396 useModMap: BOOL 397 </para> 398 <para> 399 clearLocks: BOOL 400 </para> 401 <para> 402 latchToLock: BOOL 403 </para> 404 </entry> 405<entry> 406<itemizedlist> 407<listitem> 408 <para>Key press and release events have the same effect as for <emphasis> 409SA_SetMods</emphasis> 410; if no keys were operated simultaneously with the latching modifier key, key 411release events have the following additional effects: 412 </para> 413</listitem> 414<listitem> 415 <para>Modifiers that were unlocked due to <emphasis> 416clearLocks</emphasis> 417 have no further effect. 418 </para> 419</listitem> 420<listitem> 421 <para>If <emphasis> 422latchToLock</emphasis> 423 is set, key release locks and then unlatches any remaining action modifiers 424that are already latched. 425 </para> 426</listitem> 427<listitem> 428 <para>Finally, key release latches any action modifiers that were not used by 429the <emphasis> 430clearLocks</emphasis> 431 or <emphasis> 432latchToLock</emphasis> 433 flags. 434 </para> 435</listitem> 436</itemizedlist> 437</entry> 438 </row> 439 <row> 440 <entry> 441 <para> 442 <emphasis> 443SA_LockMods 444 </emphasis> 445 </para> 446 <para> 447 mods: MOD_DEF 448 </para> 449 <para> 450 useModMap: BOOL 451 </para> 452 <para> 453 noLock: BOOL 454 </para> 455 <para> 456 noUnlock: BOOL 457 </para> 458 </entry> 459<entry> 460<itemizedlist> 461<listitem> 462 <para>Key press sets the base and possibly the locked state of any action 463modifiers. If <emphasis> 464noLock</emphasis> 465 is <emphasis> 466True</emphasis> 467, only the base state is changed. 468 </para> 469</listitem> 470<listitem> 471 <para>For key release events, clears any action modifiers in the keyboard’s 472base modifiers, provided that no other key which affects the same modifiers is 473down. If <emphasis> 474noUnlock</emphasis> 475 is <emphasis> 476False</emphasis> 477 and any of the action modifiers were locked before the corresponding key press 478occurred, key release unlocks them. 479 </para> 480</listitem> 481</itemizedlist> 482</entry> 483 </row> 484 <row> 485 <entry> 486 <para> 487 <emphasis> 488SA_SetGroup 489</emphasis> 490 </para> 491 <para> 492 group: INT8 493 </para> 494 <para> 495 groupAbsolute: BOOL 496 </para> 497 <para> 498 clearLocks: BOOL 499 </para> 500 </entry> 501<entry> 502<itemizedlist> 503<listitem> 504 <para>If <emphasis> 505groupAbsolute</emphasis> 506 is set, key press events change the base keyboard group to <emphasis> 507group</emphasis> 508; otherwise, they add <emphasis> 509group</emphasis> 510 to the base keyboard group. In either case, the resulting effective keyboard 511group is brought back into range depending on the value of the <emphasis> 512GroupsWrap</emphasis> 513 control for the keyboard. 514 </para> 515</listitem> 516<listitem> 517 <para>If an <emphasis> 518SA_ISOLock</emphasis> 519 key is pressed while this key is held down, key release has no effect, 520otherwise it cancels the effects of the press. 521 </para> 522</listitem> 523<listitem> 524 <para>If no keys were operated simultaneously with this key and <emphasis> 525clearLocks</emphasis> 526 is set, key release also sets the locked keyboard group to <emphasis> 527Group1</emphasis> 528. 529 </para> 530</listitem> 531</itemizedlist> 532</entry> 533 </row> 534 <row> 535 <entry> 536 <para> 537 <emphasis> 538SA_LatchGroup 539 </emphasis> 540 </para> 541 <para> 542 group: INT8 543 </para> 544 <para> 545 groupAbsolute: BOOL 546 </para> 547 <para> 548 clearLocks: BOOL 549 </para> 550 <para> 551 latchToLock: BOOL 552 </para> 553 </entry> 554<entry> 555<itemizedlist> 556<listitem> 557 <para>Key press and release events have the same effect as an <emphasis> 558SA_SetGroup</emphasis> 559 action; if no keys were operated simultaneously with the latching group key 560and the <emphasis> 561clearLocks</emphasis> 562 flag was not set or had no effect, key release has the following additional 563effects: 564 </para> 565</listitem> 566<listitem> 567 <para>If <emphasis> 568latchToLock</emphasis> 569 is set and the latched keyboard group is non-zero, the key release adds the 570delta applied by the corresponding key press to the locked keyboard group and 571subtracts it from the latched keyboard group. The locked and effective keyboard 572group are brought back into range according to the value of the global 573<emphasis> 574GroupsWrap</emphasis> 575 control for the keyboard. 576 </para> 577</listitem> 578<listitem> 579 <para>Otherwise, key release adds the key press delta to the latched keyboard 580group. 581 </para> 582</listitem> 583</itemizedlist> 584</entry> 585 </row> 586 <row> 587 <entry> 588 <para> 589 <emphasis> 590SA_LockGroup 591 </emphasis> 592 </para> 593 <para> 594 group: INT8 595 </para> 596 <para> 597 groupAbsolute: BOOL 598 </para> 599 </entry> 600<entry> 601<itemizedlist> 602<listitem> 603 <para>If <emphasis> 604groupAbsolute</emphasis> 605 is set, key press sets the locked keyboard group to <emphasis> 606group</emphasis> 607. Otherwise, key press adds <emphasis> 608group</emphasis> 609 to the locked keyboard group. In either case, the resulting locked and 610effective group is brought back into range depending on the value of the 611<emphasis> 612GroupsWrap</emphasis> 613 control for the keyboard. 614 </para> 615</listitem> 616<listitem> 617 <para>Key release has no effect. 618 </para> 619</listitem> 620</itemizedlist> 621</entry> 622 </row> 623 <row> 624 <entry> 625 <para> 626 <emphasis> 627SA_MovePtr 628</emphasis> 629 </para> 630 <para> 631 x, y: INT16 632 </para> 633 <para> 634 noAccel: BOOL 635 </para> 636 <para> 637 absoluteX: BOOL 638 </para> 639 <para> 640 absoluteY: BOOL 641 </para> 642 </entry> 643<entry> 644<itemizedlist> 645<listitem> 646 <para>If <emphasis> 647MouseKeys</emphasis> 648 are not enabled, this action behaves like <emphasis> 649SA_NoAction</emphasis> 650, otherwise this action cancels any pending repeat key timers for this key and 651has the following additional effects. 652 </para> 653</listitem> 654<listitem> 655 <para>Key press generates a core pointer <emphasis> 656MotionNotify</emphasis> 657 event instead of the usual <emphasis> 658KeyPress</emphasis> 659. If <emphasis> 660absoluteX</emphasis> 661 is <emphasis> 662True</emphasis> 663, <emphasis> 664x</emphasis> 665 specifies the new pointer X coordinate, otherwise <emphasis> 666x</emphasis> 667 is added to the current pointer X coordinate; <emphasis> 668absoluteY</emphasis> 669 and <emphasis> 670y</emphasis> 671 specify the new Y coordinate in the same way. 672 </para> 673</listitem> 674<listitem> 675 <para>If <emphasis> 676noAccel</emphasis> 677 is <emphasis> 678False</emphasis> 679, and the <emphasis> 680MouseKeysAccel</emphasis> 681 keyboard control is enabled, key press also initiates the mouse keys timer for 682this key; every time this timer expires, the cursor moves again. The distance 683the cursor moves in these subsequent events is determined by the mouse keys 684acceleration as described in <link linkend='The_MouseKeysAccel_Control'>The 685MouseKeysAccel Control</link>. 686 </para> 687</listitem> 688<listitem> 689 <para>Key release disables the mouse keys timer (if it was initiated by the 690corresponding key press) but has no other effect and is ignored (does not 691generate an event of any type). 692 </para> 693</listitem> 694</itemizedlist> 695</entry> 696 </row> 697 <row> 698 <entry> 699 <para> 700 <emphasis> 701SA_PtrBtn 702 </emphasis> 703 </para> 704 <para> 705 button: CARD8 706 </para> 707 <para> 708 count: CARD8 709 </para> 710 <para> 711 useDfltBtn: BOOL 712 </para> 713 </entry> 714<entry> 715<itemizedlist> 716<listitem> 717 <para>If <emphasis> 718MouseKeys</emphasis> 719 are not enabled, this action behaves like <emphasis> 720SA_NoAction</emphasis> 721. 722 </para> 723</listitem> 724<listitem> 725 <para>If <emphasis> 726useDfltBtn</emphasis> 727 is set, the event is generated for the current default core button. Otherwise, 728the event is generated for the button specified by <emphasis> 729button</emphasis> 730. 731 </para> 732</listitem> 733<listitem> 734 <para>If the mouse button specified for this action is logically down, the 735key press and corresponding release are ignored and have no effect. 736 </para> 737</listitem> 738<listitem> 739 <para>Otherwise, key press causes one or more core pointer button events 740instead of the usual key press. If <emphasis> 741count</emphasis> 742 is <emphasis> 7430</emphasis> 744, key press generates a single <emphasis> 745ButtonPress</emphasis> 746 event; if <emphasis> 747count</emphasis> 748 is greater than <emphasis> 7490</emphasis> 750, key press generates <emphasis> 751count</emphasis> 752 pairs of <emphasis> 753ButtonPress</emphasis> 754 and <emphasis> 755ButtonRelease</emphasis> 756 events. 757 </para> 758</listitem> 759<listitem> 760 <para>If <emphasis> 761count</emphasis> 762 is <emphasis> 7630</emphasis> 764, key release generates a core pointer <emphasis> 765ButtonRelease</emphasis> 766 which matches the event generated by the corresponding key press; if count is 767non-zero, key release does not cause a <emphasis> 768ButtonRelease</emphasis> 769 event. Key release never causes a key release event. 770 </para> 771</listitem> 772</itemizedlist> 773</entry> 774 </row> 775 <row> 776 <entry> 777 <para> 778 <emphasis> 779SA_LockPtrBtn 780</emphasis> 781 </para> 782 <para> 783 button: BUTTON 784 </para> 785 <para> 786 noLock: BOOL 787 </para> 788 <para> 789 noUnlock: BOOL 790 </para> 791 <para> 792 useDfltBtn: BOOL 793 </para> 794 </entry> 795<entry> 796<itemizedlist> 797<listitem> 798 <para>If <emphasis> 799MouseKeys</emphasis> 800 are not enabled, this action behaves like <emphasis> 801SA_NoAction</emphasis> 802. 803 </para> 804</listitem> 805<listitem> 806 <para>Otherwise, if the button specified by <emphasis> 807useDfltBtn</emphasis> 808 and <emphasis> 809button</emphasis> 810 is not locked, key press causes a <emphasis> 811ButtonPress</emphasis> 812 instead of a key press and locks the button. If the button is already locked 813or if <emphasis> 814noLock</emphasis> 815 is <emphasis> 816True</emphasis> 817, key press is ignored and has no effect. 818 </para> 819</listitem> 820<listitem> 821 <para>If the corresponding key press was ignored, and if <emphasis> 822noUnlock</emphasis> 823 is <emphasis> 824False</emphasis> 825, key release generates a <emphasis> 826ButtonRelease</emphasis> 827 event instead of a key release event and unlocks the specified button. If the 828corresponding key press locked a button, key release is ignored and has no 829effect. 830 </para> 831</listitem> 832</itemizedlist> 833</entry> 834 </row> 835 <row> 836 <entry> 837 <para> 838 <emphasis> 839SA_SetPtrDflt 840</emphasis> 841 </para> 842 <para> 843 affect: CARD8 844 </para> 845 <para> 846 value: CARD8 847 </para> 848 <para> 849 dfltBtnAbs: BOOL 850 </para> 851 </entry> 852<entry> 853<itemizedlist> 854<listitem> 855 <para>If <emphasis> 856MouseKeys</emphasis> 857 are not enabled, this action behaves like <emphasis> 858SA_NoAction</emphasis> 859. 860 </para> 861</listitem> 862<listitem> 863 <para>Otherwise, both key press and key release are ignored, but key press 864changes the pointer value specified by <emphasis> 865affect </emphasis> 866to <emphasis> 867value</emphasis> 868, as follows: 869 </para> 870</listitem> 871<listitem> 872 <para>If <emphasis> 873which</emphasis> 874 is <emphasis> 875SA_AffectDfltBtn</emphasis> 876, <emphasis> 877value</emphasis> 878 and <emphasis> 879dfltBtnAbs</emphasis> 880 specify the default pointer button used by the various pointer actions as 881follow: If <emphasis> 882dfltBtnAbs </emphasis> 883is True, value specifies the button to be used, otherwise, <emphasis> 884value</emphasis> 885 specifies the amount to be added to the current default button. In either 886case, illegal button choices are wrapped back into range. 887 </para> 888</listitem> 889</itemizedlist> 890</entry> 891 </row> 892 <row> 893 <entry> 894 <para> 895 <emphasis> 896SA_ISOLock 897</emphasis> 898 </para> 899 <para> 900 dfltIsGroup: <emphasis> 901False 902</emphasis> 903 </para> 904 <para> 905 mods: MOD_DEF 906 </para> 907 <para> 908 useModMap: BOOL 909 </para> 910 <para> 911 noLock: BOOL 912 </para> 913 <para> 914 noUnlock: BOOL 915 </para> 916 <para> 917 noAffectMods: BOOL 918 </para> 919 <para> 920 noAffectGrp: BOOL 921 </para> 922 <para> 923 noAffectPtr: BOOL 924 </para> 925 <para> 926 noAffectCtrls: BOOL 927 </para> 928 <para> 929or 930 </para> 931 <para> 932 dfltIsGroup: <emphasis> 933True 934</emphasis> 935 </para> 936 <para> 937 group: INT8 938 </para> 939 <para> 940 groupAbsolute: BOOL 941 </para> 942 <para> 943 noAffectMods: BOOL 944 </para> 945 <para> 946 noAffectGrp: BOOL 947 </para> 948 <para> 949 noAffectPtr: BOOL 950 </para> 951 <para> 952 noAffectCtrls: BOOL 953 </para> 954 </entry> 955<entry> 956<itemizedlist> 957<listitem> 958 <para>If <emphasis> 959dfltIsGroup</emphasis> 960 is <emphasis> 961True</emphasis> 962, key press sets the base group specified by <emphasis> 963groupAbsolute</emphasis> 964 and <emphasis> 965group</emphasis> 966. Otherwise, key press sets the action modifiers in the keyboard’s base 967modifiers. 968 </para> 969</listitem> 970<listitem> 971 <para>Key release clears the base modifiers or group that were set by the key 972press; it may have additional effects if no other appropriate actions occur 973simultaneously with the <emphasis> 974SA_ISOLock</emphasis> 975 operation. 976 </para> 977</listitem> 978<listitem> 979 <para>If <emphasis> 980noAffectMods</emphasis> 981 is <emphasis> 982False</emphasis> 983, any <emphasis> 984SA_SetMods</emphasis> 985 or <emphasis> 986SA_LatchMods</emphasis> 987 actions that occur simultaneously with the <emphasis> 988ISOLock</emphasis> 989 action are treated as <emphasis> 990SA_LockMods</emphasis> 991 instead. 992 </para> 993</listitem> 994<listitem> 995 <para>If <emphasis> 996noAffectGrp</emphasis> 997 is <emphasis> 998False</emphasis> 999, any <emphasis> 1000SA_SetGroup</emphasis> 1001 or <emphasis> 1002SA_LatchGroup</emphasis> 1003 actions that occur simultaneously with this action are treated as <emphasis> 1004SA_LockGroup</emphasis> 1005 actions instead. 1006 </para> 1007</listitem> 1008<listitem> 1009 <para>If <emphasis> 1010noAffectPtr</emphasis> 1011 is <emphasis> 1012False</emphasis> 1013, <emphasis> 1014SA_PtrBtn</emphasis> 1015 actions that occur simultaneously with the <emphasis> 1016SA_ISOLock</emphasis> 1017 action are treated as <emphasis> 1018SA_LockPtrBtn</emphasis> 1019 actions instead. 1020 </para> 1021</listitem> 1022<listitem> 1023 <para>If <emphasis> 1024noAffectCtrls</emphasis> 1025 is <emphasis> 1026False</emphasis> 1027, any <emphasis> 1028SA_SetControls</emphasis> 1029 actions that occur simultaneously with the <emphasis> 1030SA_ISOLock</emphasis> 1031 action are treated as <emphasis> 1032SA_LockControls</emphasis> 1033 actions instead. 1034 </para> 1035</listitem> 1036<listitem> 1037 <para>If no other actions were transformed by the <emphasis> 1038SA_ISOLock</emphasis> 1039 action, key release locks the group or modifiers specified by the action 1040arguments. 1041 </para> 1042</listitem> 1043</itemizedlist> 1044</entry> 1045 </row> 1046 <row> 1047 <entry><emphasis> 1048SA_TerminateServer</emphasis> 1049 </entry> 1050<entry> 1051<itemizedlist> 1052<listitem> 1053 <para>Key press terminates the server. Key release is ignored. 1054 </para> 1055</listitem> 1056<listitem> 1057 <para>This action is optional; servers are free to ignore it. If ignored, it 1058behaves like <emphasis> 1059SA_NoAction</emphasis> 1060. 1061 </para> 1062</listitem> 1063</itemizedlist> 1064</entry> 1065 </row> 1066 <row> 1067 <entry> 1068 <para> 1069 <emphasis> 1070SA_SwitchScreen 1071</emphasis> 1072 </para> 1073 <para> 1074 num: INT8 1075 </para> 1076 <para> 1077 switchApp: BOOL 1078 </para> 1079 <para> 1080 screenAbs: BOOL 1081 </para> 1082</entry> 1083<entry> 1084<itemizedlist> 1085<listitem> 1086 <para>If the server supports this action and multiple screens or displays 1087(either virtual or real), this action changes to the active screen indicated by 1088<emphasis> 1089num</emphasis> 1090 and <emphasis> 1091screenAbs</emphasis> 1092. If <emphasis> 1093screenAbs</emphasis> 1094 is <emphasis> 1095True</emphasis> 1096, num specifies the index of the new screen; otherwise, num specifies an offset 1097from the current screen to the new screen. 1098 </para> 1099</listitem> 1100<listitem> 1101 <para>If <emphasis> 1102switchApp</emphasis> 1103 is <emphasis> 1104False</emphasis> 1105, it should switch to another screen on the same server. Otherwise it should 1106switch to another X server or application which shares the same physical 1107display. 1108 </para> 1109</listitem> 1110<listitem> 1111 <para>This action is optional; servers are free to ignore the action or any 1112of its flags if they do not support the requested behavior. If the action is 1113ignored, it behaves like <emphasis> 1114SA_NoAction</emphasis> 1115, otherwise neither key press nor release generate an event. 1116 </para> 1117</listitem> 1118</itemizedlist> 1119</entry> 1120 </row> 1121 <row> 1122 <entry> 1123 <para><emphasis>SA_SetControls</emphasis></para> 1124 <para>controls: KB_BOOLCTRLMASK</para> 1125 </entry> 1126 <entry> 1127 <itemizedlist> 1128 <listitem> 1129 <para> 1130Key press enables any boolean controls that are specified in <emphasis> 1131controls</emphasis> 1132 and not already enabled at the time of the key press. Key release disables any 1133controls that were enabled by the corresponding key press. This action can 1134cause <emphasis> 1135XkbControlsNotify</emphasis> 1136 events. 1137 </para> 1138 </listitem> 1139 </itemizedlist> 1140 </entry> 1141 </row> 1142 <row> 1143 <entry> 1144 <para><emphasis>SA_LockControls</emphasis></para> 1145 <para> 1146 controls: KB_BOOLCTRLMASK 1147 </para> 1148 <para> 1149 noLock: BOOL 1150 </para> 1151 <para> 1152 noUnlock: BOOL 1153 </para> 1154 </entry> 1155 <entry> 1156<itemizedlist> 1157<listitem> 1158 <para>If <emphasis> 1159noLock</emphasis> 1160 is <emphasis> 1161False</emphasis> 1162, key press locks and enables any controls that are specified in <emphasis> 1163controls</emphasis> 1164 and not already locked at the time of the key press. 1165</para> 1166<para> 1167If <emphasis> 1168noUnlock</emphasis> 1169 is <emphasis> 1170False</emphasis> 1171, key release unlocks and disables any controls that are specified in <emphasis> 1172controls</emphasis> 1173 and were not enabled at the time of the corresponding key press. 1174 </para> 1175</listitem> 1176</itemizedlist> 1177</entry> 1178 </row> 1179 <row> 1180 <entry> 1181 <para> 1182 <emphasis> 1183SA_ActionMessage</emphasis> 1184: 1185 pressMsg: BOOL 1186 </para> 1187 <para> 1188 releaseMsg: BOOL 1189 </para> 1190 <para> 1191 genEvent: BOOL 1192 </para> 1193 <para> 1194 message: STRING 1195 </para> 1196 </entry> 1197<entry> 1198<itemizedlist> 1199<listitem> 1200 <para>if <emphasis> 1201pressMsg</emphasis> 1202 is <emphasis> 1203True</emphasis> 1204, key press generates an <emphasis> 1205XkbActionMessage</emphasis> 1206 event which reports the keycode, event type and the contents of <emphasis> 1207message</emphasis> 1208. 1209 </para> 1210</listitem> 1211<listitem> 1212 <para>If <emphasis> 1213releaseMsg</emphasis> 1214 is <emphasis> 1215True</emphasis> 1216, key release generates an <emphasis> 1217XkbActionMessage</emphasis> 1218 event which reports the keycode, event type and contents of <emphasis> 1219message</emphasis> 1220. 1221 </para> 1222</listitem> 1223<listitem> 1224 <para>If <emphasis> 1225genEvent</emphasis> 1226 is <emphasis> 1227True</emphasis> 1228, both press and release generate key press and key release events, regardless 1229of whether they also cause an <emphasis> 1230XkbActionMessage</emphasis> 1231. 1232 </para> 1233</listitem> 1234</itemizedlist> 1235</entry> 1236 </row> 1237 <row> 1238 <entry> 1239 <para> 1240 <emphasis> 1241SA_RedirectKey 1242</emphasis> 1243 </para> 1244 <para> 1245 newKey: KEYCODE 1246 </para> 1247 <para> 1248 modsMask: KEYMASK 1249 </para> 1250 <para> 1251 mods: KEYMASK 1252 </para> 1253 <para> 1254 vmodsMask: CARD16 1255 </para> 1256 <para> 1257 vmods: CARD16 1258 </para> 1259 </entry> 1260<entry> 1261<itemizedlist> 1262<listitem> 1263 <para>Key press causes a key press event for the key specified by <emphasis> 1264newKey</emphasis> 1265 instead of for the actual key. The state reported in this event reports of the 1266current effective modifiers changed as follow: Any real modifiers specified in 1267<emphasis> 1268modsMask</emphasis> 1269 are set to corresponding values from <emphasis> 1270mods</emphasis> 1271. Any real modifiers bound to the virtual modifiers specified in <emphasis> 1272vmodsMask</emphasis> 1273 are either set or cleared, depending on the corresponding value in <emphasis> 1274vmods</emphasis> 1275. If the real and virtual modifier definitions specify conflicting values for a 1276single modifier, the real modifier definition has priority. 1277 </para> 1278</listitem> 1279<listitem> 1280 <para>Key release causes a key release event for the key specified by 1281<emphasis> 1282newKey</emphasis> 1283; the state field for this event consists of the effective keyboard modifiers 1284at the time of the release, changed as described above. 1285 </para> 1286</listitem> 1287<listitem> 1288 <para>The <emphasis> 1289SA_RedirectKey</emphasis> 1290 action normally redirects to another key on the same device as the key or 1291button which caused the event, unless that device does not belong to the input 1292extension KEYCLASS, in which case this action causes an event on the core 1293keyboard device. 1294 </para> 1295</listitem> 1296</itemizedlist> 1297</entry> 1298 </row> 1299 <row> 1300 <entry> 1301 <para> 1302 <emphasis> 1303SA_DeviceBtn 1304</emphasis> 1305 </para> 1306 <para> 1307 count: CARD8 1308 </para> 1309 <para> 1310 button: BUTTON 1311 </para> 1312 <para> 1313 device: CARD8 1314 </para> 1315 </entry> 1316<entry> 1317<itemizedlist> 1318<listitem> 1319 <para>The <emphasis> 1320device</emphasis> 1321 field specifies the ID of an extension device; the <emphasis> 1322button</emphasis> 1323 field specifies the index of a button on that device. If the button specified 1324by this action is logically down, the key press and corresponding release are 1325ignored and have no effect. If the device or button specified by this action 1326are illegal, this action behaves like <emphasis> 1327SA_NoAction</emphasis> 1328. 1329 </para> 1330</listitem> 1331<listitem> 1332 <para>Otherwise, key press causes one or more input extension device button 1333events instead of the usual key press event. If <emphasis> 1334count</emphasis> 1335 is <emphasis> 13360</emphasis> 1337, key press generates a single <emphasis> 1338DeviceButtonPress</emphasis> 1339 event; if <emphasis> 1340count</emphasis> 1341 is greater than <emphasis> 13420</emphasis> 1343, key press generates <emphasis> 1344count</emphasis> 1345 pairs of <emphasis> 1346DeviceButtonPress</emphasis> 1347 and <emphasis> 1348DeviceButtonRelease</emphasis> 1349 events. 1350 </para> 1351</listitem> 1352<listitem> 1353 <para>If <emphasis> 1354count</emphasis> 1355 is <emphasis> 13560</emphasis> 1357, key release generates an input extension <emphasis> 1358DeviceButtonRelease</emphasis> 1359 which matches the event generated by the corresponding key press; if count is 1360non-zero, key release does not cause a <emphasis> 1361DeviceButtonRelease</emphasis> 1362 event. Key release never causes a key release event. 1363 </para> 1364</listitem> 1365</itemizedlist> 1366</entry> 1367 </row> 1368 <row> 1369 <entry> 1370 <para> 1371 <emphasis> 1372SA_LockDeviceBtn 1373</emphasis> 1374 </para> 1375 <para> 1376 button: BUTTON 1377 </para> 1378 <para> 1379 device: CARD8 1380 </para> 1381 <para> 1382 noLock: BOOL 1383 </para> 1384 <para> 1385 noUnlock: BOOL 1386 </para> 1387 </entry> 1388<entry> 1389<itemizedlist> 1390<listitem> 1391 <para>The <emphasis> 1392device</emphasis> 1393 field specifies the ID of an extension device; the <emphasis> 1394button</emphasis> 1395 field specifies the index of a button on that device. If the device or button 1396specified by this action are illegal, it behaves like <emphasis> 1397SA_NoAction</emphasis> 1398. 1399 </para> 1400</listitem> 1401<listitem> 1402 <para>Otherwise, if the specified button is not locked and if <emphasis> 1403noLock</emphasis> 1404 is <emphasis> 1405False</emphasis> 1406, key press causes an input extension <emphasis> 1407DeviceButtonPress</emphasis> 1408 event instead of a key press event and locks the button. If the button is 1409already locked or if <emphasis> 1410noLock</emphasis> 1411 is <emphasis> 1412True</emphasis> 1413, key press is ignored and has no effect. 1414 </para> 1415</listitem> 1416<listitem> 1417 <para>If the corresponding key press was ignored, and if <emphasis> 1418noUnlock</emphasis> 1419 is <emphasis> 1420False</emphasis> 1421, key release generates an input extension <emphasis> 1422DeviceButtonRelease</emphasis> 1423 event instead of a core protocol or input extension key release event and 1424unlocks the specified button. If the corresponding key press locked a button, 1425key release is ignored and has no effect. 1426 </para> 1427</listitem> 1428</itemizedlist> 1429</entry> 1430 </row> 1431 <row> 1432 <entry> 1433<para> 1434 <emphasis> 1435SA_DeviceValuator 1436</emphasis> 1437</para> 1438<para> 1439 <emphasis> 1440device</emphasis> 1441: CARD8 1442</para> 1443<para> 1444 <emphasis> 1445val1What</emphasis> 1446: SA_DVOP 1447</para> 1448<para> 1449 <emphasis> 1450val1</emphasis> 1451: CARD8 1452</para> 1453<para> 1454 <emphasis> 1455val1Value</emphasis> 1456: INT8 1457</para> 1458<para> 1459 <emphasis> 1460val1Scale</emphasis> 1461: 0...7 1462</para> 1463<para> 1464 <emphasis> 1465val2What</emphasis> 1466: BOOL 1467</para> 1468<para> 1469 <emphasis> 1470val2</emphasis> 1471: CARD8 1472</para> 1473<para> 1474 <emphasis> 1475val2Value</emphasis> 1476: INT8 1477</para> 1478<para> 1479 <emphasis> 1480val2Scale</emphasis> 1481: 0...7 1482</para> 1483</entry> 1484<entry> 1485<itemizedlist> 1486<listitem> 1487 <para>The <emphasis> 1488device</emphasis> 1489 field specifies the ID of an extension device; <emphasis> 1490val1</emphasis> 1491 and <emphasis> 1492val2</emphasis> 1493 specify valuators on that device. If <emphasis> 1494device</emphasis> 1495 is illegal or if neither <emphasis> 1496val1</emphasis> 1497 nor <emphasis> 1498val2</emphasis> 1499 specifies a legal valuator, this action behaves like <emphasis> 1500SA_NoAction</emphasis> 1501. 1502 </para> 1503</listitem> 1504<listitem> 1505 <para>If <emphasis> 1506valn</emphasis> 1507 specifies a legal valuator and <emphasis> 1508valnWhat</emphasis> 1509 is not <emphasis> 1510SA_IgnoreVal</emphasis> 1511, the specified value is adjusted as specified by <emphasis> 1512valnWhat</emphasis> 1513: 1514 </para> 1515</listitem> 1516<listitem> 1517 <para>If <emphasis> 1518valnWhat</emphasis> 1519 is <emphasis> 1520SA_SetValMin</emphasis> 1521, <emphasis> 1522valn</emphasis> 1523 is set to its minimum legal value. 1524 </para> 1525</listitem> 1526<listitem> 1527 <para>If <emphasis> 1528valnWhat</emphasis> 1529 is <emphasis> 1530SA_SetValCenter</emphasis> 1531, <emphasis> 1532valn</emphasis> 1533 is centered (to (max-min)/2). 1534 </para> 1535</listitem> 1536<listitem> 1537 <para>If <emphasis> 1538valnWhat</emphasis> 1539 is <emphasis> 1540SA_SetValMax</emphasis> 1541, <emphasis> 1542valn</emphasis> 1543 is set to its maximum legal value. 1544 </para> 1545</listitem> 1546<listitem> 1547 <para>if <emphasis> 1548valnWhat</emphasis> 1549 is <emphasis> 1550SA_SetValRelative</emphasis> 1551, <mediaobject> 1552 <imageobject> <imagedata format="SVG" fileref="XKBproto-4.svg"/> 1553 </imageobject> 1554 </mediaobject> 1555 1556 is added to <emphasis> 1557valn</emphasis> 1558. 1559 </para> 1560</listitem> 1561<listitem> 1562 <para>if <emphasis> 1563valnWhat</emphasis> 1564 is <emphasis> 1565SA_SetValAbsolute</emphasis> 1566, <emphasis> 1567valn</emphasis> 1568 is set to <mediaobject> 1569 <imageobject> <imagedata format="SVG" fileref="XKBproto-5.svg"/> 1570 </imageobject> 1571 </mediaobject> 1572 1573. 1574 </para> 1575</listitem> 1576<listitem> 1577 <para>Illegal values for <emphasis> 1578SA_SetValRelative</emphasis> 1579 or <emphasis> 1580SA_SetValAbsolute</emphasis> 1581 are clamped into range. 1582 </para> 1583</listitem> 1584</itemizedlist> 1585</entry> 1586 </row> 1587</tbody> 1588</tgroup> 1589</informaltable> 1590 1591<para> 1592If <emphasis> 1593StickyKeys</emphasis> 1594 are enabled, all <emphasis> 1595SA_SetMods</emphasis> 1596 and <emphasis> 1597SA_SetGroup</emphasis> 1598 actions act like <emphasis> 1599SA_LatchMods</emphasis> 1600 and <emphasis> 1601SA_LatchGroup</emphasis> 1602 respectively. If the <emphasis> 1603LatchToLock</emphasis> 1604 AccessX option is set, either action behaves as if both the <emphasis> 1605SA_ClearLocks</emphasis> 1606 and <emphasis> 1607SA_LatchToLock</emphasis> 1608 flags are set. 1609</para> 1610 1611 1612<para> 1613Actions which cause an event from another key or from a button on another 1614device immediately generate the specified event. These actions do not consider 1615the behavior or actions (if any) that are bound to the key or button to which 1616the event is redirected. 1617</para> 1618 1619 1620<para> 1621Core events generated by server actions contain the keyboard state that was in 1622effect at the time the key event occurred; the reported state does not reflect 1623any changes in state that occur as a result of the actions bound to the key 1624event that caused them. 1625</para> 1626 1627 1628<para> 1629Events sent to clients that have not issued an <emphasis> 1630XkbUseExtension</emphasis> 1631 request contain a compatibility state in place of the actual XKB keyboard 1632state. See <link linkend='Effects_of_XKB_on_Core_Protocol_Events'>Effects of XKB on Core 1633Protocol Events</link> for a description of this compatibility mapping. 1634</para> 1635 1636 1637</sect1> 1638<sect1 id='Delivering_a_Key_or_Button_Event_to_a_Client'> 1639<title>Delivering a Key or Button Event to a Client</title> 1640 1641<para> 1642The window and client that receive core protocol and input extension key or 1643button events are determined using the focus policy, window hierarchy and 1644passive grabs as specified by the core protocol and the input extension, with 1645the following changes: 1646</para> 1647 1648<itemizedlist> 1649<listitem> 1650 <para>A passive grab triggers if the modifier state specified in the grab 1651matches the grab compatibility state (described in <link 1652linkend='Compatibility_Components_of_Keyboard_State'>Compatibility Components of Keyboard 1653State</link>). Clients can choose to use the XKB grab state instead by setting 1654the <emphasis> 1655GrabsUseXKBState</emphasis> 1656 per-client flag. This flag affects all passive grabs that are requested by the 1657client which sets it but does not affect passive grabs that are set by any 1658other client. 1659 </para> 1660</listitem> 1661<listitem> 1662 <para>The state field of events which trigger a passive grab reports the XKB 1663or compatibility grab state in effect at the time the grab is triggered; the 1664state field of the corresponding release event reports the corresponding grab 1665state in effect when the key or button is released. 1666 </para> 1667</listitem> 1668<listitem> 1669 <para>If the <emphasis> 1670LookupStateWhenGrabbed</emphasis> 1671 per-client flag is set, all key or button events that occur while a keyboard 1672or pointer grab is active contain the XKB or compatibility lookup state, 1673depending on the value of the <emphasis> 1674GrabsUseXKBState</emphasis> 1675 per-client flag. If <emphasis> 1676LookupStateWhenGrabbed</emphasis> 1677 is not set, they include the XKB or compatibility grab state, instead. 1678 </para> 1679</listitem> 1680<listitem> 1681 <para>Otherwise, the state field of events that do not trigger a passive grab 1682report is derived from the XKB effective modifiers and group, as described in 1683<link linkend='Computing_A_State_Field_from_an_XKB_State'>Computing A State Field from an 1684XKB State</link>. 1685 </para> 1686</listitem> 1687<listitem> 1688 <para>If a key release event is the result of an autorepeating key that is 1689being held down, and the client to which the event is reported has requested 1690detectable autorepeat (see <link linkend='Detectable_Autorepeat'> 1691Detectable Autorepeat</link>), the event is not delivered to the client. 1692 </para> 1693</listitem> 1694</itemizedlist> 1695 1696<para> 1697The following section explains the intent of the XKB interactions with core 1698protocol grabs and the reason that the per-client flags are needed. 1699</para> 1700 1701 1702<sect2 id='XKB_Interactions_With_Core_Protocol_Grabs'> 1703<title>XKB Interactions With Core Protocol Grabs</title> 1704 1705<para> 1706XKB provides the separate lookup and grab states to help work around some 1707difficulties with the way the core protocol specifies passive grabs. 1708Unfortunately, many clients work around those problems differently, and the way 1709that XKB handles grabs and reports keyboard state can sometimes interact with 1710those client workarounds in unexpected and unpleasant ways. 1711</para> 1712 1713 1714<para> 1715To provide more reasonable behavior for clients that are aware of XKB without 1716causing problems for clients that are unaware of XKB, this extension provides 1717two per-client flags that specify the way that XKB and the core protocol should 1718interact. 1719</para> 1720 1721<itemizedlist> 1722<listitem> 1723 <para>The largest problems arise from the fact that an XKB state field 1724encodes an explicit keyboard group in bits 13-14 (as described in <link 1725linkend='Computing_A_State_Field_from_an_XKB_State'>Computing A State Field from an XKB 1726State</link>), while pre-XKB clients use one of the eight keyboard modifiers 1727to select an alternate keyboard group. To make existing clients behave 1728reasonably, XKB normally uses the compatibility grab state instead of the XKB 1729grab state to determine whether or not a passive grab is triggered. XKB-aware 1730clients can set the <emphasis> 1731GrabsUseXKBState</emphasis> 1732 per-client flag to indicate that they are specifying passive grabs using an 1733XKB state. 1734 </para> 1735</listitem> 1736<listitem> 1737 <para>Some toolkits start an active grab when a passive grab is triggered, in 1738order to have more control over the conditions under which the grab is 1739terminated. Unfortunately, the fact that XKB reports a different state in 1740events that trigger or terminate grabs means that this grab simulation can fail 1741to terminate the grab under some conditions. To work around this problem, XKB 1742normally reports the grab state in all events whenever a grab is active. 1743Clients which do not use active grabs like this can set the <emphasis> 1744LookupStateWhenGrabbed</emphasis> 1745 per-client flag in order to receive the same state component whether or not a 1746grab is active. 1747 </para> 1748<para> 1749The <emphasis> 1750GrabsUseXKBState</emphasis> 1751 per-client flag also applies to the state of events sent while a grab is 1752active. If it is set, events during a grab contain the XKB lookup or grab 1753state; by default, events during a grab contain the compatibility lookup or 1754grab state.</para> 1755</listitem> 1756</itemizedlist> 1757 1758<para> 1759The state used to trigger a passive grab is controlled by the setting of the 1760<emphasis> 1761GrabsUseXKBState</emphasis> 1762 per-client flag at the time the grab is registered. Changing this flag does 1763not affect existing passive grabs. 1764</para> 1765</sect2> 1766</sect1> 1767</chapter> 1768
