aboutsummaryrefslogtreecommitdiff
path: root/libXt/specs/CH11.xml
blob: 92e46dc57bd5ad0cc7a486c6dfc954775b63da5a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
5419
5420
5421
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443
5444
5445
5446
5447
5448
5449
5450
5451
5452
5453
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486
5487
5488
5489
5490
5491
5492
5493
5494
5495
5496
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507
5508
5509
5510
5511
5512
5513
5514
5515
5516
5517
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528
5529
5530
5531
5532
5533
5534
5535
5536
5537
5538
<chapter id='Utility_Functions'>
<title>Utility Functions</title>
<para>
The Intrinsics provide a number of utility functions that you can use to
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
Determine the number of elements in an array.
    </para>
  </listitem>
  <listitem>
    <para>
Translate strings to widget instances.
    </para>
  </listitem>
  <listitem>
    <para>
Manage memory usage.
    </para>
  </listitem>
  <listitem>
    <para>
Share graphics contexts.
    </para>
  </listitem>
  <listitem>
    <para>
Manipulate selections.
    </para>
  </listitem>
  <listitem>
    <para>
Merge exposure events into a region.
    </para>
  </listitem>
  <listitem>
    <para>
Translate widget coordinates.
    </para>
  </listitem>
  <listitem>
    <para>
Locate a widget given a window id.
    </para>
  </listitem>
  <listitem>
    <para>
Handle errors.
    </para>
  </listitem>
  <listitem>
    <para>
Set the WM_COLORMAP_WINDOWS property.
    </para>
  </listitem>
  <listitem>
    <para>
Locate files by name with string substitutions.
    </para>
  </listitem>
  <listitem>
    <para>
Register callback functions for external agents.
    </para>
  </listitem>
  <listitem>
    <para>
Locate all the displays of an application context.
    </para>
  </listitem>
</itemizedlist>

<sect1 id="Determining_the_Number_of_Elements_in_an_Array">
<title>Determining the Number of Elements in an Array</title>
<para>
To determine the number of elements in a fixed-size array, use
<xref linkend='XtNumber' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtNumber'>
<funcprototype>
<funcdef>Cardinal <function>XtNumber</function></funcdef>
  <paramdef>ArrayType <parameter>array</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>array</emphasis>
    </term>
    <listitem>
      <para>
Specifies a fixed-size array of arbitrary type.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtNumber' xrefstyle='select: title'/>
macro returns the number of elements allocated to the array.
</para>
</sect1>

<sect1 id="Translating_Strings_to_Widget_Instances">
<title>Translating Strings to Widget Instances</title>
<para>
To translate a widget name to a widget instance, use
<xref linkend='XtNameToWidget' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtNameToWidget'>
<funcprototype>
<funcdef>Widget <function>XtNameToWidget</function></funcdef>
   <paramdef>Widget <parameter>reference</parameter></paramdef>
   <paramdef>String <parameter>names</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>reference</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget from which the search is to start.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>names</emphasis>
    </term>
    <listitem>
      <para>
Specifies the partially qualified name of the desired widget.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtNameToWidget' xrefstyle='select: title'/>
function searches for a descendant of the <emphasis remap='I'>reference</emphasis>
widget whose name matches the specified names.  The <emphasis remap='I'>names</emphasis> parameter
specifies a simple object name or a series of simple object name
components separated by periods or asterisks.
<xref linkend='XtNameToWidget' xrefstyle='select: title'/>
returns the descendant with the shortest name matching the specification
according to the following rules, where child is either a pop-up child
or a normal child if the widget's class is a subclass of
Composite :
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
Enumerate the object subtree rooted at the reference widget in
breadth-first order, qualifying the name of each object with the
names of all its ancestors up to, but not including, the reference
widget.  The ordering between children of a common parent is
not defined.
    </para>
  </listitem>
  <listitem>
    <para>
Return the first object in the enumeration that matches the
specified name, where each component of <emphasis remap='I'>names</emphasis> matches exactly the
corresponding component of the qualified object name and asterisk
matches any series of components, including none.
    </para>
  </listitem>
  <listitem>
    <para>
If no match is found, return NULL.
    </para>
  </listitem>
</itemizedlist>
<para>
Since breadth-first traversal is specified, the descendant with the
shortest matching name (i.e., the fewest number of components), if any,
will always be returned.  However, since the order of enumeration of
children is undefined and since the Intrinsics do not require that all
children of a widget have unique names,
<xref linkend='XtNameToWidget' xrefstyle='select: title'/>
may return any
child that matches if there are multiple objects in the subtree with
the same name.  Consecutive separators (periods or asterisks)
including at least one asterisk are treated as a single asterisk.
Consecutive periods are treated as a single period.
</para>
</sect1>

<sect1 id="Managing_Memory_Usage">
<title>Managing Memory Usage</title>
<para>
The Intrinsics memory management functions provide uniform checking for
null pointers and error reporting on memory allocation errors.
These functions are completely compatible with their standard C language
runtime counterparts
<function>malloc</function>,
<function>calloc</function>,
<function>realloc</function>,
and
<function>free</function>
with the following added functionality:
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
<xref linkend='XtMalloc' xrefstyle='select: title'/>,
<xref linkend='XtCalloc' xrefstyle='select: title'/>,
and
<xref linkend='XtRealloc' xrefstyle='select: title'/>
give an error if there is not enough memory.
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtFree' xrefstyle='select: title'/>
simply returns if passed a NULL pointer.
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtRealloc' xrefstyle='select: title'/>
simply allocates new storage if passed a NULL pointer.
    </para>
  </listitem>
</itemizedlist>
<para>
See the standard C library documentation on
<function>malloc</function>,
<function>calloc</function>,
<function>realloc</function>,
and
<function>free</function>
for more information.
</para>

<para>
To allocate storage, use
<xref linkend='XtMalloc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtMalloc'>
<funcprototype>
<funcdef>char * <function>XtMalloc</function></funcdef>
   <paramdef>Cardinal <parameter>size</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>size</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of bytes desired.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtMalloc' xrefstyle='select: title'/>
function returns a pointer to a block of storage of at least
the specified <emphasis remap='I'>size</emphasis> bytes.
If there is insufficient memory to allocate the new block,
<xref linkend='XtMalloc' xrefstyle='select: title'/>
calls
<xref linkend='XtErrorMsg' xrefstyle='select: title'/>.
</para>

<para>
To allocate and initialize an array, use
<xref linkend='XtCalloc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtCalloc'>
<funcprototype>
<funcdef>char * <function>XtCalloc</function></funcdef>
   <paramdef>Cardinal <parameter>num</parameter></paramdef>
   <paramdef>Cardinal <parameter>size</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>num</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of array elements to allocate.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>size</emphasis>
    </term>
    <listitem>
      <para>
Specifies the size of each array element in bytes.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtCalloc' xrefstyle='select: title'/>
function allocates space for the specified number of array elements
of the specified size and initializes the space to zero.
If there is insufficient memory to allocate the new block,
<xref linkend='XtCalloc' xrefstyle='select: title'/>
calls
<xref linkend='XtErrorMsg' xrefstyle='select: title'/>.
<xref linkend='XtCalloc' xrefstyle='select: title'/>
returns the address of the allocated storage.
</para>

<para>
To change the size of an allocated block of storage, use
<xref linkend='XtRealloc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtRealloc'>
<funcprototype>
<funcdef>char *<function>XtRealloc</function></funcdef>
   <paramdef>char *<parameter>ptr</parameter></paramdef>
   <paramdef>Cardinal <parameter>num</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>ptr</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the old storage allocated with
<xref linkend='XtMalloc' xrefstyle='select: title'/>,
<xref linkend='XtCalloc' xrefstyle='select: title'/>,
or
<xref linkend='XtRealloc' xrefstyle='select: title'/>,
or NULL.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num</emphasis>
    </term>
    <listitem>
      <para>
Specifies number of bytes desired in new storage.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtRealloc' xrefstyle='select: title'/>
function changes the size of a block of storage, possibly moving it.
Then it copies the old contents (or as much as will fit) into the new block
and frees the old block.
If there is insufficient memory to allocate the new block,
<xref linkend='XtRealloc' xrefstyle='select: title'/>
calls
<xref linkend='XtErrorMsg' xrefstyle='select: title'/>.
If <emphasis remap='I'>ptr</emphasis> is NULL,
<xref linkend='XtRealloc' xrefstyle='select: title'/>
simply calls
<xref linkend='XtMalloc' xrefstyle='select: title'/>.
<xref linkend='XtRealloc' xrefstyle='select: title'/>
then returns the address of the new block.
</para>

<para>
To free an allocated block of storage, use
<xref linkend='XtFree' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtFree'>
<funcprototype>
<funcdef>void <function>XtFree</function></funcdef>
   <paramdef>char *<parameter>ptr</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>ptr</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to a block of storage allocated with
<xref linkend='XtMalloc' xrefstyle='select: title'/>,
<xref linkend='XtCalloc' xrefstyle='select: title'/>,
or
<xref linkend='XtRealloc' xrefstyle='select: title'/>,
or NULL.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtFree' xrefstyle='select: title'/>
function returns storage, allowing it to be reused.
If <emphasis remap='I'>ptr</emphasis> is NULL,
<xref linkend='XtFree' xrefstyle='select: title'/>
returns immediately.
</para>

<para>
To allocate storage for a new instance of a type, use
<xref linkend='XtNew' xrefstyle='select: title'/>.
</para>


<funcsynopsis id='XtNew'>
<funcprototype>
<funcdef>type <function>XtNew</function></funcdef>
      <paramdef>type <parameter>t</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies a previously declared type.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtNew' xrefstyle='select: title'/>
returns a pointer to the allocated storage.
If there is insufficient memory to allocate the new block,
<xref linkend='XtNew' xrefstyle='select: title'/>
calls
<xref linkend='XtErrorMsg' xrefstyle='select: title'/>.
<xref linkend='XtNew' xrefstyle='select: title'/>
is a convenience macro that calls
<xref linkend='XtMalloc' xrefstyle='select: title'/>
with the following arguments specified:
</para>
<literallayout >
((type *) XtMalloc((unsigned) sizeof(type)))
</literallayout>
<para>
The storage allocated by
<xref linkend='XtNew' xrefstyle='select: title'/>
should be freed using
<xref linkend='XtFree' xrefstyle='select: title'/>.
</para>

<para>
To copy an instance of a string, use
<xref linkend='XtNewString' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtNewString'>
<funcprototype>
<funcdef>String <function>XtNewString</function></funcdef>
   <paramdef>String <parameter>string</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>string</emphasis>
    </term>
    <listitem>
      <para>
Specifies a previously declared string.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtNewString' xrefstyle='select: title'/>
returns a pointer to the allocated storage.
If there is insufficient memory to allocate the new block,
<xref linkend='XtNewString' xrefstyle='select: title'/>
calls
<xref linkend='XtErrorMsg' xrefstyle='select: title'/>.
<xref linkend='XtNewString' xrefstyle='select: title'/>
is a convenience macro that calls
<xref linkend='XtMalloc' xrefstyle='select: title'/>
with the following arguments specified:
</para>
<literallayout >
(strcpy(XtMalloc((unsigned)strlen(str) + 1), str))
</literallayout>
<para>
The storage allocated by
<xref linkend='XtNewString' xrefstyle='select: title'/>
should be freed using
<xref linkend='XtFree' xrefstyle='select: title'/>.
</para>
</sect1>

<sect1 id="Sharing_Graphics_Contexts">
<title>Sharing Graphics Contexts</title>
<para>
The Intrinsics provide a mechanism whereby cooperating objects can share a
graphics context (GC), thereby reducing both the number of GCs
created and the total number of server calls in any given application.
The mechanism is a simple caching scheme
and allows for clients to declare both modifiable and nonmodifiable
fields of the shared GCs.
</para>

<para>
To obtain a shareable GC with modifiable fields, use
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAllocateGC'>
<funcprototype>
<funcdef>GC <function>XtAllocateGC</function></funcdef>
   <paramdef>Widget <parameter>object</parameter></paramdef>
   <paramdef>Cardinal <parameter>depth</parameter></paramdef>
   <paramdef>XtGCMask <parameter>value_mask</parameter></paramdef>
   <paramdef>XGCValues *<parameter>values</parameter></paramdef>
   <paramdef>XtGCMask <parameter>dynamic_mask</parameter></paramdef>
   <paramdef>XtGCMask <parameter>unused_mask</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>object</emphasis>
    </term>
    <listitem>
      <para>
Specifies an object, giving the screen for which the
returned GC is valid.  Must be of class Object or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>depth</emphasis>
    </term>
    <listitem>
      <para>
Specifies the depth for which the returned GC is valid, or 0.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value_mask</emphasis>
    </term>
    <listitem>
      <para>
Specifies fields of the GC that are initialized from <emphasis remap='I'>values</emphasis>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>values</emphasis>
    </term>
    <listitem>
      <para>
Specifies the values for the initialized fields.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>dynamic_mask</emphasis>
    </term>
    <listitem>
      <para>
Specifies fields of the GC that will be modified by the caller.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>unused_mask</emphasis>
    </term>
    <listitem>
      <para>
Specifies fields of the GC that will not be needed by the caller.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>
function returns a shareable GC that may be
modified by the client.  The <emphasis remap='I'>screen</emphasis> field of the specified
widget or of the nearest widget ancestor of the specified
object and the specified <emphasis remap='I'>depth</emphasis> argument supply
the root and drawable depths for which the GC is to be
valid.  If <emphasis remap='I'>depth</emphasis> is zero, the depth is taken from the
<emphasis remap='I'>depth</emphasis> field of the specified widget or of the nearest
widget ancestor of the specified object.
</para>

<para>
The <emphasis remap='I'>value_mask</emphasis> argument specifies fields of the GC
that are initialized with the respective member of the
<emphasis remap='I'>values</emphasis> structure.  The <emphasis remap='I'>dynamic_mask</emphasis> argument specifies fields
that the caller intends to modify during program execution.
The caller must ensure that the corresponding GC field is set
prior to each use of the GC.  The <emphasis remap='I'>unused_mask</emphasis> argument
specifies fields of the GC that are of no interest to the
caller.  The caller may make no assumptions about the contents
of any fields specified in <emphasis remap='I'>unused_mask</emphasis>.  The caller may assume
that at all times all fields not specified in either
<emphasis remap='I'>dynamic_mask</emphasis> or <emphasis remap='I'>unused_mask</emphasis> have their default value if not
specified in <emphasis remap='I'>value_mask</emphasis> or the value specified by <emphasis remap='I'>values</emphasis>.
If a field is specified in both <emphasis remap='I'>value_mask</emphasis> and <emphasis remap='I'>dynamic_mask</emphasis>,
the effect is as if it were specified only in <emphasis remap='I'>dynamic_mask</emphasis>
and then immediately set to the value in <emphasis remap='I'>values</emphasis>.  If a field
is set in <emphasis remap='I'>unused_mask</emphasis> and also in either <emphasis remap='I'>value_mask</emphasis> or
<emphasis remap='I'>dynamic_mask</emphasis>, the specification in <emphasis remap='I'>unused_mask</emphasis> is ignored.
</para>

<para>
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>
tries to minimize the number of unique GCs
created by comparing the arguments with those of previous
calls and returning an existing GC when there are no
conflicts.
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>
may modify and return an existing GC if it was allocated with a
nonzero <emphasis remap='I'>unused_mask</emphasis>.
</para>

<para>
To obtain a shareable GC with no modifiable fields, use
<xref linkend='XtGetGC' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetGC'>
<funcprototype>
<funcdef>GC <function>XtGetGC</function></funcdef>
   <paramdef>Widget <parameter>object</parameter></paramdef>
   <paramdef>XtGCMask <parameter>value_mask</parameter></paramdef>
   <paramdef>XGCValues *<parameter>values</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>object</emphasis>
    </term>
    <listitem>
      <para>
Specifies an object, giving the screen and depth for which the
returned GC is valid.  Must be of class Object or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value_mask</emphasis>
    </term>
    <listitem>
      <para>
Specifies which fields of the <emphasis remap='I'>values</emphasis> structure are specified.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>values</emphasis>
    </term>
    <listitem>
      <para>
Specifies the actual values for this GC.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtGetGC' xrefstyle='select: title'/>
function returns a shareable, read-only GC.
The parameters to this function are the same as those for
<function>XCreateGC</function>
except that an Object is passed instead of a Display.
<xref linkend='XtGetGC' xrefstyle='select: title'/>
is equivalent to
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>
with <emphasis remap='I'>depth</emphasis>, <emphasis remap='I'>dynamic_mask</emphasis>, and <emphasis remap='I'>unused_mask</emphasis> all zero.
</para>

<para>
<xref linkend='XtGetGC' xrefstyle='select: title'/>
shares only GCs in which all values in the GC returned by
<function>XCreateGC</function>
are the same.
In particular, it does not use the <emphasis remap='I'>value_mask</emphasis> provided to
determine which fields of the GC a widget considers relevant.
The <emphasis remap='I'>value_mask</emphasis> is used only to tell the server which fields should be
filled in from <emphasis remap='I'>values</emphasis> and which it should fill in with default values.
</para>

<para>
To deallocate a shared GC when it is no longer needed, use
<xref linkend='XtReleaseGC' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtReleaseGC'>
<funcprototype>
<funcdef>void <function>XtReleaseGC</function></funcdef>
   <paramdef>Widget <parameter>object</parameter></paramdef>
   <paramdef>GC <parameter>gc</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>object</emphasis>
    </term>
    <listitem>
      <para>
Specifies any object on the Display for which the GC was created.  Must be of class Object or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>gc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the shared GC obtained with either
<xref linkend='XtAllocateGC' xrefstyle='select: title'/>
or
<xref linkend='XtGetGC' xrefstyle='select: title'/>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
References to shareable GCs are counted and a free request is generated to the
server when the last user of a given GC releases it.
</para>
</sect1>

<sect1 id="Managing_Selections">
<title>Managing Selections</title>
<para>
Arbitrary widgets in multiple applications can communicate
with each other by means of the Intrinsics global selection mechanism,
which conforms to the specifications in the <emphasis remap='I'>Inter-Client Communication Conventions Manual.</emphasis>.
The Intrinsics supply functions for providing and receiving selection data in
one logical piece (atomic transfers)
or in smaller logical segments (incremental transfers).
</para>

<para>
The incremental interface is provided for a selection owner or
selection requestor that cannot or prefers not to pass the selection
value to and from the Intrinsics in a single call.  For instance,
either an application that is running on a machine with limited memory
may not be able to store the entire selection value in memory or a
selection owner may already have the selection value available in
discrete chunks, and it would be more efficient not to have to
allocate additional storage to copy the pieces contiguously.  Any
owner or requestor that prefers to deal with the selection value in
segments can use the incremental interfaces to do so.
The transfer between the selection owner or requestor and the Intrinsics is not
required to match the underlying
transport protocol between the application and the X server;
the Intrinsics will break too large a selection
into smaller pieces for transport if necessary
and will coalesce a selection transmitted incrementally if the value
was requested atomically.
</para>

<sect2 id='Setting_and_Getting_the_Selection_Timeout_Value'>
<title>Setting and Getting the Selection Timeout Value</title>
<para>
To set the Intrinsics selection timeout, use
<xref linkend='XtAppSetSelectionTimeout' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppSetSelectionTimeout'>
<funcprototype>
<funcdef>void <function>XtAppSetSelectionTimeout</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>unsigned long <parameter>timeout</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>timeout</emphasis>
    </term>
    <listitem>
      <para>
Specifies the selection timeout in milliseconds.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
To get the current selection timeout value, use
<xref linkend='XtAppGetSelectionTimeout' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppGetSelectionTimeout'>
<funcprototype>
<funcdef>unsigned long <function>XtAppGetSelectionTimeout</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtAppGetSelectionTimeout' xrefstyle='select: title'/>
function returns the current selection timeout value in milliseconds.
The selection timeout is the time within which the two communicating
applications must respond to one another.
The initial timeout value is set by the
selectionTimeout
application resource as retrieved by
<xref linkend='XtDisplayInitialize' xrefstyle='select: title'/>.
If
selectionTimeout
is not specified,
the default is five seconds.
</para>
</sect2>

<sect2 id="Using_Atomic_Transfers">
<title>Using Atomic Transfers</title>
<para>
When using atomic transfers, the owner will completely
process one selection request at a time.
The owner may consider each request individually,
since there is no possibility for overlap
between evaluation of two requests.
</para>

<sect3 id="Atomic_Transfer_Procedures">
<title>Atomic Transfer Procedures</title>
<para>
The following procedures are used by the selection owner when
providing selection data in a single unit.
</para>

<para>
The procedure pointer specified by the owner to supply the selection
data to the Intrinsics is of type
<xref linkend='XtConvertSelectionProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtConvertSelectionProc'>
<funcprototype>
<funcdef>typedef Boolean <function>(*XtConvertSelectionProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>target</parameter></paramdef>
   <paramdef>Atom *<parameter>type_return</parameter></paramdef>
   <paramdef>XtPointer *<parameter>value_return</parameter></paramdef>
   <paramdef>unsigned long *<parameter>length_return</parameter></paramdef>
   <paramdef>int *<parameter>format_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that currently owns this selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom naming the selection requested
(for example,
<function>XA_PRIMARY</function>
or
<function>XA_SECONDARY ).</function>
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the target type of the selection that has been requested,
which indicates the desired information about the selection
(for example, File Name, Text, Window).
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to an atom into which the property type of the
converted value of the selection is to be stored.
For instance, either File Name or Text might have property type
<function>XA_STRING</function>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which a pointer to the converted value of the
selection is to be stored.
The selection owner is responsible for allocating this storage.
If the selection owner has provided an
<xref linkend='XtSelectionDoneProc' xrefstyle='select: title'/>
for the selection,
this storage is owned by the selection owner;
otherwise, it is owned by the Intrinsics selection mechanism,
which frees it by calling
<xref linkend='XtFree' xrefstyle='select: title'/>
when it is done with it.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>length_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the number of elements in <emphasis remap='I'>value_return</emphasis>,
each of size indicated by <emphasis remap='I'>format_return</emphasis>, is to be stored.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>format_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the size in bits of the data elements
of the selection value is to be stored.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called by the Intrinsics selection mechanism
to get the value of a selection as a given type
from the current selection owner.
It returns
<function>True</function>
if the owner successfully converted the selection to the target type or
<function>False</function>
otherwise.
If the procedure returns
<function>False</function>,
the values of the return arguments are undefined.
Each
<xref linkend='XtConvertSelectionProc' xrefstyle='select: title'/>
should respond to target value
<function>TARGETS</function>
by returning a value containing the list of the targets
into which it is
prepared to convert the selection.
The value returned in
<emphasis remap='I'>format_return</emphasis> must be one of 8, 16, or 32 to allow the server to
byte-swap the data if necessary.
</para>

<para>
This procedure does not need to worry about responding to the
MULTIPLE or the TIMESTAMP target values (see
<xref linkend='Window_Creation_Convenience_Routine' />
in the <olink targetdoc='icccm' targetptr='icccm'>Inter-Client Communication Conventions Manual.</olink>).
A selection request with
the MULTIPLE target type is transparently transformed into a
series of calls to this procedure, one for each target type, and a
selection request with the TIMESTAMP target value is answered
automatically by the Intrinsics using the time specified in the
call to
<xref linkend='XtOwnSelection' xrefstyle='select: title'/>
or
<xref linkend='XtOwnSelectionIncremental' xrefstyle='select: title'/>.
</para>

<para>
To retrieve the
<function>SelectionRequest</function>
event that triggered the
<xref linkend='XtConvertSelectionProc' xrefstyle='select: title'/>
procedure, use
<xref linkend='XtGetSelectionRequest' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetSelectionRequest'>
<funcprototype>
<funcdef>XSelectionRequestEvent *<function>XtGetSelectionRequest</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>XtRequestId <parameter>request_id</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that currently owns this selection.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the selection being processed.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>request_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies the requestor id in the case of incremental
selections, or NULL in the case of atomic transfers.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtGetSelectionRequest' xrefstyle='select: title'/>
may be called only from within an
<xref linkend='XtConvertSelectionProc' xrefstyle='select: title'/>
procedure and returns a pointer to the
<function>SelectionRequest</function>
event that caused the conversion procedure to be invoked.
<emphasis remap='I'>Request_id</emphasis> specifies a unique id for the individual request in the
case that multiple incremental transfers are outstanding.  For atomic
transfers, <emphasis remap='I'>request_id</emphasis> must be specified as NULL.  If no
<function>SelectionRequest</function>
event is being processed for the specified
<emphasis remap='I'>widget</emphasis>, <emphasis remap='I'>selection</emphasis>, and <emphasis remap='I'>request_id</emphasis>,
<xref linkend='XtGetSelectionRequest' xrefstyle='select: title'/>
returns NULL.
</para>

<para>
The procedure pointer specified by the owner when it desires
notification upon losing ownership is of type
<xref linkend='XtLoseSelectionProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtLoseSelectionProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtLoseSelectionProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that has lost selection ownership.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom naming the selection.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called by the Intrinsics selection mechanism
to inform the specified widget that it has lost the given selection.
Note that this procedure does not ask the widget to relinquish the
selection ownership; it is merely informative.
</para>

<para>
The procedure pointer specified by the owner when it desires
notification of receipt of the data or when it manages the storage
containing the data is of type
<xref linkend='XtSelectionDoneProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSelectionDoneProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtSelectionDoneProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>target</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that owns the converted selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom naming the selection that was converted.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the target type to which the conversion was done.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called by the Intrinsics selection mechanism
to inform the selection owner that a selection requestor has successfully
retrieved a selection value.
If the selection owner has registered an
<xref linkend='XtSelectionDoneProc' xrefstyle='select: title'/>,
it should expect it to be called once for each conversion that it performs,
after the converted value has been successfully transferred
to the requestor.
If the selection owner has registered an
<xref linkend='XtSelectionDoneProc' xrefstyle='select: title'/>,
it also owns the storage containing the converted
selection value.
</para>
</sect3>
<sect3 id="Getting_the_Selection_Value">
<title>Getting the Selection Value</title>
<para>
The procedure pointer specified by the requestor to receive the
selection data from the Intrinsics is of type
<xref linkend='XtSelectionCallbackProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSelectionCallbackProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtSelectionCallbackPro)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>type</parameter></paramdef>
   <paramdef>XtPointer <parameter>value</parameter></paramdef>
   <paramdef>unsigned long *<parameter>length</parameter></paramdef>
   <paramdef>int *<parameter>format</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that requested the selection value.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies a value passed in by the widget when it requested the
selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the name of the selection that was requested.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies the representation type of the selection value (for example,
<function>XA_STRING ).</function>
Note that it is not the target that was requested (which the client
must remember for itself), but the type that
is used to represent the target.
The special symbolic constant
<function>XT_CONVERT_FAIL</function>
is used to indicate that the selection conversion failed because the
selection owner did not respond within the Intrinsics selection timeout
interval.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the selection value.
The requesting client owns this storage and is responsible for freeing it
by calling
<xref linkend='XtFree' xrefstyle='select: title'/>
when it is done with it.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>length</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of elements in <emphasis remap='I'>value</emphasis>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>format</emphasis>
    </term>
    <listitem>
      <para>
Specifies the size in bits of the data in each element of <emphasis remap='I'>value</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called by the Intrinsics selection mechanism to deliver the
requested selection to the requestor.
</para>

<para>
If the
<function>SelectionNotify</function>
event returns a property of
<function>None</function>,
meaning the conversion has been refused because there is no owner for the
specified selection or the owner cannot convert the selection to the
requested target for any reason, the procedure is called with a value
of NULL and a length of zero.
</para>

<para>
To obtain the selection value in a single logical unit, use
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
or
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetSelectionValue'>
<funcprototype>
<funcdef>void <function>XtGetSelectionValue</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Atom <parameter>target</parameter></paramdef>
   <paramdef>XtSelectionCallbackProc <parameter>callback</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired; for example,
<function>XA_PRIMARY</function>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the type of information needed about the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure to be called when the selection value
has been obtained.
Note that this is how the selection value is communicated back to the client.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies additional data to be passed to the specified procedure
when it is called.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the selection request was
initiated.
This should be the timestamp of the event that triggered this request;
the value
<function>CurrentTime</function>
is not acceptable.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
function requests the value of the selection converted to
the target type.
The specified callback is called at some time after
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
is called, when the selection value is received from the X server.
It may be called before or after
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
returns.
For more information about <emphasis remap='I'>selection</emphasis>,
<emphasis remap='I'>target</emphasis>, and
<emphasis remap='I'>time</emphasis>, see
<olink targetdoc='icccm' targetptr='Use_of_Selection_Atoms'>Section 2.6</olink> in the
<olink targetdoc='icccm' targetptr='icccm'>Inter-Client Communication Conventions Manual.</olink>.
</para>

<funcsynopsis id='XtGetSelectionValues'>
<funcprototype>
<funcdef>void <function>XtGetSelectionValues</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>targets</parameter></paramdef>
   <paramdef>int <parameter>count</parameter></paramdef>
   <paramdef>XtSelectionCallbackProc <parameter>callback</parameter></paramdef>
   <paramdef>XtPointer *<parameter>client_data</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired (that is, primary or secondary).
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>targets</emphasis>
    </term>
    <listitem>
      <para>
Specifies the types of information needed about the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>count</emphasis>
    </term>
    <listitem>
      <para>
Specifies the length of the <emphasis remap='I'>targets</emphasis> and <emphasis remap='I'>client_data</emphasis> lists.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the callback procedure
to be called with each selection value obtained.
Note that this is how the selection values are communicated back to the
client.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies a list of additional data values, one for each target type,
that are passed to the callback procedure when it is called for that target.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the selection request was
initiated.
This should be the timestamp of the event that triggered this request;
the value
<function>CurrentTime</function>
is not acceptable.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>
function is similar to multiple calls to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
except that it guarantees that no other client can assert ownership
between requests and therefore that all the conversions will refer to
the same selection value.  The callback is invoked once for each
target value with the corresponding client data.
For more information about <emphasis remap='I'>selection</emphasis>, <emphasis remap='I'>target</emphasis>, and
<emphasis remap='I'>time</emphasis>, see
<olink targetdoc='icccm' targetptr='Use_of_Selection_Atoms'>section 2.6</olink>
in the <emphasis remap='I'>Inter-Client Communication Conventions Manual.</emphasis>.
</para>
</sect3>
<sect3 id="Setting_the_Selection_Owner">
<title>Setting the Selection Owner</title>
<para>
To set the selection owner and indicate that the selection value will
be provided in one piece, use
<xref linkend='XtOwnSelection' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtOwnSelection'>
<funcprototype>
<funcdef>Boolean <function>XtOwnSelection</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
   <paramdef>XtConvertSelectionProc <parameter>convert_proc</parameter></paramdef>
   <paramdef>XtLoseSelectionProc <parameter>lose_selection</parameter></paramdef>
   <paramdef>XtSelectionDoneProc <parameter>done_proc</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that wishes to become the owner.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the name of the selection (for example,
<function>XA_PRIMARY ).</function>
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the ownership request was
initiated.
This should be the timestamp of the event that triggered ownership;
the value
<function>CurrentTime</function>
is not acceptable.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>convert_proc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure to be called whenever a client requests the
current value of the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>lose_selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure to be called whenever the widget has
lost selection ownership, or NULL if the owner is not interested in being
called back.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>done_proc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure called
after the requestor has received the selection value, or NULL if the
owner is not
interested in being called back.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtOwnSelection' xrefstyle='select: title'/>
function informs the Intrinsics selection mechanism that a
widget wishes to own a selection.
It returns
<function>True</function>
if the widget successfully becomes the owner and
<function>False</function>
otherwise.
The widget may fail to become the owner if some other widget
has asserted ownership at a time later than this widget.
The widget can lose selection ownership either
because some other widget asserted later ownership of the selection
or because the widget voluntarily gave up ownership of the selection.
The lose_selection procedure is not called
if the widget fails to obtain selection ownership in the first place.
</para>

<para>
If a done_proc is specified, the client owns the storage allocated
for passing the value to the Intrinsics.  If <emphasis remap='I'>done_proc</emphasis> is NULL,
the convert_proc must allocate storage using
<xref linkend='XtMalloc' xrefstyle='select: title'/>,
<xref linkend='XtRealloc' xrefstyle='select: title'/>,
or
<xref linkend='XtCalloc' xrefstyle='select: title'/>,
and the value specified is freed by the
Intrinsics when the transfer is complete.
</para>

<para>
Usually, a selection owner maintains ownership indefinitely until some
other widget requests ownership, at which time
the Intrinsics selection mechanism informs the previous owner that it
has lost ownership of the selection.
However, in response to some user actions
(for example, when a user deletes the information selected),
the application may wish to explicitly inform the Intrinsics
by using
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>
that it no longer is to be the selection owner.
</para>

<funcsynopsis id='XtDisownSelection'>
<funcprototype>
<funcdef>void <function>XtDisownSelection</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that wishes to relinquish ownership.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom naming the selection being given up.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the request to
relinquish selection ownership was initiated.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>
function informs the Intrinsics selection mechanism that
the specified widget is to lose ownership of the selection.
If the widget does not currently own the selection, either
because it lost the selection
or because it never had the selection to begin with,
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>
does nothing.
</para>

<para>
After a widget has called
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>,
its convert procedure is not called even if a request arrives later
with a timestamp during the period that this widget owned the selection.
However, its done procedure is called if a conversion that started
before the call to
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>
finishes after the call to
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>.
</para>
</sect3>
</sect2>

<sect2 id="Using_Incremental_Transfers">
<title>Using Incremental Transfers</title>
<para>
When using the incremental interface, an owner may have to process
more than one selection request for the same selection, converted to
the same target, at the same time.  The incremental functions take a
<emphasis remap='I'>request_id</emphasis> argument, which is an identifier that is guaranteed to be
unique among all incremental requests that are active concurrently.
</para>

<para>
For example, consider the following:
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
Upon receiving a request for the selection value, the owner sends
the first segment.
    </para>
  </listitem>
  <listitem>
    <para>
While waiting to be called to provide the next segment value but
before sending it, the owner receives another request from a
different requestor for the same selection value.
    </para>
  </listitem>
  <listitem>
    <para>
To distinguish between the requests, the owner uses the request_id
value.  This allows the owner to distinguish between the first
requestor, which is asking for the second segment, and the second
requestor, which is asking for the first segment.
    </para>
  </listitem>
</itemizedlist>
<sect3 id="Incremental_Transfer_Procedures">
<title>Incremental Transfer Procedures</title>
<para>
The following procedures are used by selection owners who wish to
provide the selection data in multiple segments.
</para>

<para>
The procedure pointer specified by the incremental owner to supply the
selection data to the Intrinsics is of type
<xref linkend='XtConvertSelectionIncrProc' xrefstyle='select: title'/>.
</para>
<literallayout >
typedef XtPointer XtRequestId;
</literallayout>

<funcsynopsis id='XtConvertSelectionIncrProc'>
<funcprototype>
<funcdef>typedef Boolean <function>(*XtConvertSelectionIncrProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>target</parameter></paramdef>
   <paramdef>Atom *<parameter>type_return</parameter></paramdef>
   <paramdef>XtPointer *<parameter>value_return</parameter></paramdef>
   <paramdef>unsigned long *<parameter>length_return</parameter></paramdef>
   <paramdef>int *<parameter>format_return</parameter></paramdef>
   <paramdef>unsigned long *<parameter>max_length</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
   <paramdef>XtRequestId *<parameter>request_id</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that currently owns this selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection requested.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the type of information required about the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to an atom into which the property
type of the converted value of the selection is to be
stored.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which a pointer to the
converted value of the selection is to be stored.
The selection owner is responsible for allocating this storage.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>length_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the number of elements
in <emphasis remap='I'>value_return</emphasis>, each of size indicated by
<emphasis remap='I'>format_return</emphasis>, is to be stored.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>format_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the size in bits of the
data elements of the selection value is to be stored so that the
server may byte-swap the data if necessary.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>max_length</emphasis>
    </term>
    <listitem>
      <para>
Specifies the maximum number of bytes which may be
transferred at any one time.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the value passed in by the widget when it
took ownership of the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>request_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies an opaque identification for a specific request.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called repeatedly by the Intrinsics selection mechanism to get
the next incremental chunk of data from a selection owner who has
called
<xref linkend='XtOwnSelectionIncremental' xrefstyle='select: title'/>.
It must return
<function>True</function>
if the procedure has succeeded in converting the selection data or
<function>False</function>
otherwise.
On the first call with a particular request id, the owner must begin
a new incremental transfer for the requested selection and target.  On
subsequent calls with the same request id, the owner may assume that
the previously supplied value is no longer needed by the Intrinsics;
that is, a fixed transfer area may be allocated and returned in <emphasis remap='I'>value_return</emphasis>
for each segment to be transferred.  This procedure should store a
non-NULL value in <emphasis remap='I'>value_return</emphasis> and zero in <emphasis remap='I'>length_return</emphasis> to indicate that the
entire selection has been delivered.  After returning this final
segment, the request id may be reused by the Intrinsics to begin a
new transfer.
</para>

<para>
To retrieve the
<function>SelectionRequest</function>
event that triggered the selection conversion procedure, use
<xref linkend='XtGetSelectionRequest' xrefstyle='select: title'/>,
described in Section 11.5.2.1.
</para>

<para>
The procedure pointer specified by the incremental selection owner
when it desires notification upon no longer having ownership is of
type
<xref linkend='XtLoseSelectionIncrProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtLoseSelectionIncrProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtLoseSelectionIncrProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that has lost the selection ownership.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the value passed in by the widget when it
took ownership of the selection.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure, which is optional, is called by the Intrinsics to
inform the selection owner that it no longer owns the selection.
</para>

<para>
The procedure pointer specified by the incremental selection owner
when it desires notification of receipt of the data or when it manages
the storage containing the data is of type
<xref linkend='XtSelectionDoneIncrProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSelectionDoneIncrProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtSelectionDoneIncrProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>target</parameter></paramdef>
   <paramdef>XtRequestId *<parameter>request_id</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that owns the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection being transferred.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the target type to which the conversion was done.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>request_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies an opaque identification for a specific request.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specified the value passed in by the widget when it
took ownership of the selection.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure, which is optional, is called by the Intrinsics after
the requestor has retrieved the final (zero-length) segment of the
incremental transfer to indicate that the entire transfer is complete.
If this procedure is not specified, the Intrinsics will free only the
final value returned by the selection owner using
<xref linkend='XtFree' xrefstyle='select: title'/>.
</para>

<para>
The procedure pointer specified by the incremental selection owner to
notify it if a transfer should be terminated prematurely is of type
<xref linkend='XtCancelConvertSelectionProc' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtCancelConvertSelectionProc'>
<funcprototype>
<funcdef>typedef void <function>(*XtCancelConvertSelectionProc)</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom *<parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>target</parameter></paramdef>
   <paramdef>XtRequestId *<parameter>request_id</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that owns the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection being transferred.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the target type to which the conversion was done.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>request_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies an opaque identification for a specific request.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the value passed in by the widget when it took ownership of
the selection.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
This procedure is called by the Intrinsics when it has been determined
by means of a timeout or other mechanism that any remaining segments
of the selection no longer need to be transferred.  Upon receiving
this callback, the selection request is considered complete and the
owner can free the memory and any other resources that have been
allocated for the transfer.
</para>
</sect3>
<sect3 id="Getting_the_Selection_Value_Incrementally">
<title>Getting the Selection Value Incrementally</title>
<para>
To obtain the value of the selection using incremental transfers, use
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
or
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetSelectionValueIncremental'>
<funcprototype>
<funcdef>void <function>XtGetSelectionValueIncremental</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Atom <parameter>target</parameter></paramdef>
   <paramdef>XtSelectionCallbackProc <parameter>selection_callback</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>target</emphasis>
    </term>
    <listitem>
      <para>
Specifies the type of information needed
about the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the callback procedure to be
called to receive each data segment.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies client-specific data to be passed to
the specified callback procedure when it is invoked.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the
selection request was initiated.  This should be the
timestamp of the event that triggered this request;
the value
<function>CurrentTime</function>
is not acceptable.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
function is similar to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
except that the selection_callback procedure will
be called repeatedly upon delivery of multiple segments of the
selection value.  The end of the selection value is indicated when
<emphasis remap='I'>selection_callback</emphasis> is called with a non-NULL value of length zero,
which must still be freed by the client.  If the
transfer of the selection is aborted in the middle of a transfer
(for example, because of a timeout), the selection_callback procedure is
called with a type value equal to the symbolic constant
<function>XT_CONVERT_FAIL</function>
so that the requestor can dispose
of the partial selection value it has collected up until that point.
Upon receiving
<function>XT_CONVERT_FAIL</function>,
the requesting client must determine
for itself whether or not a partially completed data transfer is meaningful.
For more information about <emphasis remap='I'>selection</emphasis>,
<emphasis remap='I'>target</emphasis>, and
<emphasis remap='I'>time</emphasis>, see 
<olink targetdoc='icccm' targetptr='Use_of_Selection_Atoms' /> in the
<olink targetdoc='icccm' targetptr='icccm'>Inter-Client Communication Conventions Manual.</olink>
</para>

<funcsynopsis id='XtGetSelectionValuesIncremental'>
<funcprototype>
<funcdef>void <function>XtGetSelectionValuesIncremental</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Atom *<parameter>targets</parameter></paramdef>
   <paramdef>int <parameter>count</parameter></paramdef>
   <paramdef>XtSelectionCallbackProc <parameter>selection_callback</parameter></paramdef>
   <paramdef>XtPointer *<parameter>client_data</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>targets</emphasis>
    </term>
    <listitem>
      <para>
Specifies the types of information needed about
the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>count</emphasis>
    </term>
    <listitem>
      <para>
Specifies the length of the <emphasis remap='I'>targets</emphasis> and <emphasis remap='I'>client_data</emphasis> lists.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the callback procedure to be called
to receive each selection value.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies a list of client data (one for each target
type) values that are passed to the callback procedure when
it is invoked for the corresponding target.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the
selection request was initiated.  This should be the
timestamp of the event that triggered this request;
the value
<function>CurrentTime</function>
is not acceptable.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>
function is similar to
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
except that it takes a list of targets and client data.
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>
is equivalent to calling
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
successively for each <emphasis remap='I'>target/client_data</emphasis> pair except that
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>
does guarantee that all the conversions will use the same selection
value because the ownership of the selection cannot change in the
middle of the list, as would be possible when calling
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
repeatedly.
For more information about <emphasis remap='I'>selection</emphasis>, <emphasis remap='I'>target</emphasis>, and
<emphasis remap='I'>time</emphasis>, see
<olink targetdoc='icccm' targetptr='Use_of_Selection_Atoms'>Section 2.6</olink> in the
<olink targetdoc='icccm' targetptr='icccm'>Inter-Client Communication Conventions Manual.</olink>
</para>
</sect3>
<sect3 id="Setting_the_Selection_Owner_for_Incremental_Transfers">
<title>Setting the Selection Owner for Incremental Transfers</title>
<para>
To set the selection owner when using incremental transfers, use
<xref linkend='XtOwnSelectionIncremental' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtOwnSelectionIncremental'>
<funcprototype>
<funcdef>Boolean <function>XtOwnSelectionIncremental</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
   <paramdef>XtConvertSelectionIncrProc <parameter>convert_callback</parameter></paramdef>
   <paramdef>XtLoseSelectionIncrProc <parameter>lose_callback</parameter></paramdef>
   <paramdef>XtSelectionDoneIncrProc <parameter>done_callback</parameter></paramdef>
   <paramdef>XtCancelConvertSelectionProc <parameter>cancel_callback</parameter></paramdef>
   <paramdef>XtPointer <parameter>client_data</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that wishes to become the owner.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the
selection ownership request was initiated.  This should be
the timestamp of the event that triggered ownership; the value
<function>CurrentTime</function>
is not acceptable.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>convert_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure to be called whenever
the current value of the selection is requested.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>lose_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure to be called whenever
the widget has lost selection ownership, or NULL if the
owner is not interested in being notified.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>done_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the procedure called after the
requestor has received the entire selection, or NULL if
the owner is not interested in being notified.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>cancel_callback</emphasis>
    </term>
    <listitem>
      <para>
Specifies the callback procedure to be called
when a selection request aborts because a timeout expires,
or NULL if the owner is not interested in being notified.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the argument to be passed to each of
the callback procedures when they are called.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtOwnSelectionIncremental' xrefstyle='select: title'/>
procedure informs the Intrinsics
incremental selection mechanism that the specified widget wishes to
own the selection.  It returns
<function>True</function>
if the specified widget successfully becomes the selection owner or
<function>False</function>
otherwise.
For more information about <emphasis remap='I'>selection</emphasis>, <emphasis remap='I'>target</emphasis>, and
<emphasis remap='I'>time</emphasis>, see
<olink targetdoc='icccm' targetptr='Use_of_Selection_Atoms'>Section 2.6</olink> in the
<olink targetdoc='icccm' targetptr='icccm'>Inter-Client Communication Conventions Manual.</olink>
</para>

<para>
If a done_callback procedure is specified, the client owns the storage allocated
for passing the value to the Intrinsics.  If <emphasis remap='I'>done_callback</emphasis> is NULL,
the convert_callback procedure must allocate storage using
<xref linkend='XtMalloc' xrefstyle='select: title'/>,
<xref linkend='XtRealloc' xrefstyle='select: title'/>,
or
<xref linkend='XtCalloc' xrefstyle='select: title'/>,
and the final value specified is freed by the
Intrinsics when the transfer is complete.  After a selection transfer
has started, only one of the done_callback or cancel_callback
procedures is invoked to indicate completion of the transfer.
</para>

<para>
The lose_callback procedure does not indicate completion of any in-progress
transfers; it is invoked at the time a
<function>SelectionClear</function>
event is dispatched regardless of any active transfers, which are still
expected to continue.
</para>

<para>
A widget that becomes the selection owner using
<xref linkend='XtOwnSelectionIncremental' xrefstyle='select: title'/>
may use
<xref linkend='XtDisownSelection' xrefstyle='select: title'/>
to relinquish selection ownership.
</para>
</sect3>
</sect2>

<sect2 id="Setting_and_Retrieving_Selection_Target_Parameters">
<title>Setting and Retrieving Selection Target Parameters</title>
<para>
To specify target parameters for a selection request with a single target,
use
<xref linkend='XtSetSelectionParameters' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSetSelectionParameters'>
<funcprototype>
<funcdef>void <function>XtSetSelectionParameters</function></funcdef>
   <paramdef>Widget <parameter>requestor</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Atom <parameter>type</parameter></paramdef>
   <paramdef>XtPointer <parameter>value</parameter></paramdef>
   <paramdef>unsigned long <parameter>length</parameter></paramdef>
   <paramdef>int <parameter>format</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>requestor</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the atom that names the selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies the type of the property in which the parameters are passed.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the parameters.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>length</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of elements containing data in <emphasis remap='I'>value</emphasis>,
each element of a size indicated by <emphasis remap='I'>format</emphasis>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>format</emphasis>
    </term>
    <listitem>
      <para>
Specifies the size in bits of the data in the elements of <emphasis remap='I'>value</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The specified parameters are copied and stored in a new property
of the specified type and format on the requestor's window.  To initiate
a selection request with a target and these parameters, a subsequent
call to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
or to
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
specifying the same requestor widget and selection atom will generate a
<function>ConvertSelection</function>
request referring to the property containing the parameters.  If
<xref linkend='XtSetSelectionParameters' xrefstyle='select: title'/>
is called more than once with the same widget and selection without
a call to specify a request, the most recently specified parameters
are used in the subsequent request.
</para>

<para>
The possible values of <emphasis remap='I'>format</emphasis> are 8, 16, or 32.  If the format is 8,
the elements of <emphasis remap='I'>value</emphasis> are assumed to be sizeof(char);
if 16, sizeof(short); if 32, sizeof(long).
</para>

<para>
To generate a MULTIPLE
target request with parameters for any of the multiple targets of the
selection request, precede individual calls to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>
and
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
with corresponding individual calls to
<xref linkend='XtSetSelectionParameters' xrefstyle='select: title'/>,
and enclose these all within
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>
and
<function>XtSendSelectionRequest.</function>
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>
and
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>
cannot be used to make selection requests with parameterized targets.
</para>

<para>
To retrieve any target parameters needed to perform a selection conversion,
the selection owner calls
<xref linkend='XtGetSelectionParameters' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetSelectionParameters'>
<funcprototype>
<funcdef>void <function>XtGetSelectionParameters</function></funcdef>
   <paramdef>Widget <parameter>owner</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>XtRequestId <parameter>request_id</parameter></paramdef>
   <paramdef>Atom *<parameter>type_return</parameter></paramdef>
   <paramdef>XtPointer *<parameter>value_return</parameter></paramdef>
   <paramdef>unsigned long *<parameter>length_return</parameter></paramdef>
   <paramdef>int *<parameter>format_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>owner</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget that owns the specified selection.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the selection being processed.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>request_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies the requestor id in the case of incremental selections,
or NULL in the case of atomic transfers.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to an atom in which the property type
of the parameters is stored.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>value_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which a pointer to the parameters is to be stored.
A NULL is stored if no parameters accompany the request.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>length_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the number of data elements
in <emphasis remap='I'>value_return</emphasis> of size indicated by <emphasis remap='I'>format_return</emphasis> are stored.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>format_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer into which the size in bits of the parameter data
in the elements of <emphasis remap='I'>value</emphasis> is stored.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtGetSelectionParameters' xrefstyle='select: title'/>
may be called only from within an
<xref linkend='XtConvertSelectionProc' xrefstyle='select: title'/>
or from within the first call to an
<xref linkend='XtConvertSelectionIncrProc' xrefstyle='select: title'/>
with a new request_id.
</para>

<para>
It is the responsibility of the caller to free the returned parameters using
<xref linkend='XtFree' xrefstyle='select: title'/>
when the parameters are no longer needed.
</para>
</sect2>

<sect2 id="Generating_MULTIPLE_Requests">
<title>Generating MULTIPLE Requests</title>
<para>
To have the Intrinsics bundle multiple calls to make selection requests into
a single request using a <emphasis role='strong'>MULTIPLE</emphasis> target, use
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>
and
<xref linkend='XtSendSelectionRequest' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtCreateSelectionRequest'>
<funcprototype>
<funcdef>void <function>XtCreateSelectionRequest</function></funcdef>
   <paramdef>Widget <parameter>requestor</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>requestor</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
When
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>
is called, subsequent calls to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>,
and
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>,
with the requestor and selection as specified to
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>,
are bundled into a single selection request with
multiple targets.  The request is made by calling
<xref linkend='XtSendSelectionRequest' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSendSelectionRequest'>
<funcprototype>
<funcdef>void <function>XtSendSelectionRequest</function></funcdef>
   <paramdef>Widget <parameter>requestor</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
   <paramdef>Time <parameter>time</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>requestor</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>time</emphasis>
    </term>
    <listitem>
      <para>
Specifies the timestamp that indicates when the selection request was
initiated.  The value
<function>CurrentTime</function>
is not acceptable.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
When
<xref linkend='XtSendSelectionRequest' xrefstyle='select: title'/>
is called with a value of <emphasis remap='I'>requestor</emphasis> and <emphasis remap='I'>selection</emphasis> matching
a previous call to
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>,
a selection request is sent to the selection owner.
If a single target request is queued, that request is made.
If multiple targets are queued, they are bundled into a single request
with a target of MULTIPLE using the specified timestamp.
As the values are returned, the callbacks specified in
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>,
and
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>
are invoked.
</para>

<para>
Multi-threaded applications should lock the application context before
calling
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>
and release the lock after calling
<xref linkend='XtSendSelectionRequest' xrefstyle='select: title'/>
to ensure that the thread assembling the request is safe from interference
by another thread assembling a different request naming the same widget
and selection.
</para>

<para>
To relinquish the composition of a MULTIPLE request without sending it, use
<xref linkend='XtCancelSelectionRequest' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtCancelSelectionRequest'>
<funcprototype>
<funcdef>void <function>XtCancelSelectionRequest</function></funcdef>
   <paramdef>Widget <parameter>requestor</parameter></paramdef>
   <paramdef>Atom <parameter>selection</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>requestor</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making the request.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>selection</emphasis>
    </term>
    <listitem>
      <para>
Specifies the particular selection desired.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
When
<xref linkend='XtCancelSelectionRequest' xrefstyle='select: title'/>
is called, any requests queued since the last call to
<xref linkend='XtCreateSelectionRequest' xrefstyle='select: title'/>
for the same widget and selection are discarded
and any resources reserved are released.
A subsequent call to
<xref linkend='XtSendSelectionRequest' xrefstyle='select: title'/>
will not result in any request being made.
Subsequent calls to
<xref linkend='XtGetSelectionValue' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValues' xrefstyle='select: title'/>,
<xref linkend='XtGetSelectionValueIncremental' xrefstyle='select: title'/>,
or
<xref linkend='XtGetSelectionValuesIncremental' xrefstyle='select: title'/>
will not be deferred.
</para>
</sect2>

<sect2 id="Auxiliary_Selection_Properties">
<title>Auxiliary Selection Properties</title>
<para>
Certain uses of parameterized selections require clients to name
other window properties within a selection parameter.  To permit
reuse of temporary property names in these circumstances and
thereby reduce the number of unique atoms created in the server,
the Intrinsics provides two interfaces for acquiring temporary property names.
</para>

<para>
To acquire a temporary property name atom for use in a selection
request, the client may call
<xref linkend='XtReservePropertyAtom' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtReservePropertyAtom'>
<funcprototype>
<funcdef>Atom <function>XtReservePropertyAtom</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget making a selection request.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtReservePropertyAtom' xrefstyle='select: title'/>
returns an atom that may be used as a property name during selection
requests involving the specified widget.
As long as the atom remains reserved, it is unique with respect to all
other reserved atoms for the widget.
</para>

<para>
To return a temporary property name atom for reuse and to delete
the property named by that atom, use
<xref linkend='XtReleasePropertyAtom' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtReleasePropertyAtom'>
<funcprototype>
<funcdef>void <function>XtReleasePropertyAtom</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Atom <parameter>atom</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget used to reserve the property name atom.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>atom</emphasis>
    </term>
    <listitem>
      <para>
Specifies the property name atom returned by
<xref linkend='XtReservePropertyAtom' xrefstyle='select: title'/>
that is to be released for reuse.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtReleasePropertyAtom' xrefstyle='select: title'/>
marks the specified property name atom as
no longer in use and ensures that any property having that name
on the specified widget's window is deleted.  If <emphasis remap='I'>atom</emphasis> does not
specify a value returned by
<xref linkend='XtReservePropertyAtom' xrefstyle='select: title'/>
for the specified widget, the results are undefined.
</para>
</sect2>

<sect2 id="Retrieving_the_Most_Recent_Timestamp">
<title>Retrieving the Most Recent Timestamp</title>
<para>
To retrieve the timestamp from the most recent call to
<xref linkend='XtDispatchEvent' xrefstyle='select: title'/>
that contained a timestamp, use
<xref linkend='XtLastTimestampProcessed' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtLastTimestampProcessed'>
<funcprototype>
<funcdef>Time <function>XtLastTimestampProcessed</function></funcdef>
   <paramdef>Display *<parameter>display</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies an open display connection.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
If no
<function>KeyPress</function>,
<function>KeyRelease</function>,
<function>ButtonPress</function>,
<function>ButtonRelease</function>,
<function>MotionNotify</function>,
<function>EnterNotify</function>,
<function>LeaveNotify</function>,
<function>PropertyNotify</function>,
or
<function>SelectionClear</function>
event has yet been passed to
<xref linkend='XtDispatchEvent' xrefstyle='select: title'/>
for the specified display,
<xref linkend='XtLastTimestampProcessed' xrefstyle='select: title'/>
returns zero.
</para>
</sect2>

<sect2 id="Retrieving_the_Most_Recent_Event">
<title>Retrieving the Most Recent Event</title>
<para>
To retrieve the event from the most recent call to
<xref linkend='XtDispatchEvent' xrefstyle='select: title'/>
for a specific display, use
<xref linkend='XtLastEventProcessed' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtLastEventProcessed'>
<funcprototype>
<funcdef>XEvent *<function>XtLastEventProcessed</function></funcdef>
   <paramdef>Display *<parameter>display</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the display connection from which to retrieve the event.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
Returns the last event passed to
<xref linkend='XtDispatchEvent' xrefstyle='select: title'/>
for the specified display.  Returns NULL if there is no such event.
The client must not modify the contents of the returned event.
</para>
</sect2>
</sect1>

<sect1 id="Merging_Exposure_Events_into_a_Region">
<title>Merging Exposure Events into a Region</title>
<para>
The Intrinsics provide an
<xref linkend='XtAddExposureToRegion' xrefstyle='select: title'/>
utility function that merges
<function>Expose</function>
and
<function>GraphicsExpose</function>
events into a region for clients to process at once
rather than processing individual rectangles.
For further information about regions,
see <olink targetdoc='libX11' targetptr='Manipulating_Regions' />
in <olink targetdoc='libX11' targetptr='libX11'>
Xlib — C Language X Interface.</olink>.
</para>

<para>
To merge
<function>Expose</function>
and
<function>GraphicsExpose</function>
events into a region, use
<xref linkend='XtAddExposureToRegion' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAddExposureToRegion'>
<funcprototype>
<funcdef>void <function>XtAddExposureToRegion</function></funcdef>
   <paramdef>XEvent *<parameter>event</parameter></paramdef>
   <paramdef>Region <parameter>region</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>event</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the
<function>Expose</function>
or
<function>GraphicsExpose</function>
event.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>region</emphasis>
    </term>
    <listitem>
      <para>
Specifies the region object (as defined in
<function>&lt;X11/Xutil.h&gt;</function>).
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtAddExposureToRegion' xrefstyle='select: title'/>
function computes the union of the rectangle defined by the exposure
event and the specified region.
Then it stores the results back in <emphasis remap='I'>region</emphasis>.
If the event argument is not an
<function>Expose</function>
or
<function>GraphicsExpose</function>
event,
<xref linkend='XtAddExposureToRegion' xrefstyle='select: title'/>
returns without an error and without modifying <emphasis remap='I'>region</emphasis>.
</para>

<para>
This function is used by the exposure compression mechanism;
see <xref linkend='Exposure_Compression' />
</para>
</sect1>

<sect1 id="Translating_Widget_Coordinates">
<title>Translating Widget Coordinates</title>
<para>
To translate an x-y coordinate pair from widget coordinates to root
window absolute coordinates, use
<xref linkend='XtTranslateCoords' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtTranslateCoords'>
<funcprototype>
<funcdef>void <function>XtTranslateCoords</function></funcdef>
   <paramdef>Widget <parameter>w</parameter></paramdef>
   <paramdef>Position <parameter>x</parameter></paramdef>
   <paramdef>Position *<parameter>rootx_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget.  Must be of class RectObj or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>x</emphasis>
    </term>
    <listitem>
      <para></para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>y</emphasis>
    </term>
    <listitem>
      <para>
Specify the widget-relative x and y coordinates.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>rootx_return</emphasis>
    </term>
    <listitem>
      <para></para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>rooty_return</emphasis>
    </term>
    <listitem>
      <para>
Return the root-relative x and y coordinates.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
While
<xref linkend='XtTranslateCoords' xrefstyle='select: title'/>
is similar to the Xlib
<function>XTranslateCoordinates</function>
function, it does not generate a server request because all the required
information already is in the widget's data structures.
</para>
</sect1>

<sect1 id="Translating_a_Window_to_a_Widget">
<title>Translating a Window to a Widget</title>
<para>
To translate a given window and display pointer into a widget instance, use
<xref linkend='XtWindowToWidget' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtWindowToWidget'>
<funcprototype>
<funcdef>Widget <function>XtWindowToWidget</function></funcdef>
   <paramdef>Display *<parameter>display</parameter></paramdef>
   <paramdef>Window <parameter>window</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the display on which the window is defined.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>window</emphasis>
    </term>
    <listitem>
      <para>
Specifies the drawable for which you want the widget.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
If there is a realized widget whose window is the specified drawable on
the specified <emphasis remap='I'>display</emphasis>,
<xref linkend='XtWindowToWidget' xrefstyle='select: title'/>
returns that widget.
If not and if the drawable has been associated with a widget through
<xref linkend='XtRegisterDrawable' xrefstyle='select: title'/>,
<xref linkend='XtWindowToWidget' xrefstyle='select: title'/>
returns the widget associated with the drawable.  In other cases it
returns NULL.
</para>
</sect1>

<sect1 id="Handling_Errors">
<title>Handling Errors</title>
<para>
The Intrinsics allow a client to register procedures that are called
whenever a fatal or nonfatal error occurs.
These facilities are intended for both error reporting and logging
and for error correction or recovery.
</para>

<para>
Two levels of interface are provided:
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
A high-level interface that takes an error
name and class and retrieves the error message text from
an error resource database.
    </para>
  </listitem>
  <listitem>
    <para>
A low-level interface that takes a simple string to display.
    </para>
  </listitem>
</itemizedlist>
<para>
The high-level functions construct a string to pass to the lower-level
interface.
The strings may be specified in application code and are
overridden by the contents of an external systemwide file,
the "error database file".  The location and name of this file are
implementation-dependent.
</para>
<note>
<para>
The application-context-specific error handling is not
implemented on many systems, although the interfaces are
always present.
Most implementations will have just one set of error handlers
for all application contexts within a process.
If they are set for different application contexts,
the ones registered last will prevail.
</para>
</note>

<para>
To obtain the error database (for example, to merge with
an application- or widget-specific database), use
<xref linkend='XtAppGetErrorDatabase' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppGetErrorDatabase'>
<funcprototype> <funcdef>XrmDatabase *<function>XtAppGetErrorDatabase</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtAppGetErrorDatabase' xrefstyle='select: title'/>
function returns the address of the error database.
The Intrinsics do a lazy binding of the error database and do not merge in the
database file until the first call to
<xref linkend='XtAppGetErrorDatabaseText' xrefstyle='select: title'/>.
</para>

<para>
For a complete listing of all errors and warnings
that can be generated by the Intrinsics, see <xref linkend='Intrinsics_Error_Messages' />
</para>

<para>
The high-level error and warning handler procedure pointers are of type
<xref linkend='XtErrorMsgHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtErrorMsgHandler'>
<funcprototype>
<funcdef>typedef void <function>(*XtErrorMsgHandler)</function></funcdef>
   <paramdef>String <parameter>name</parameter></paramdef>
   <paramdef>String <parameter>type</parameter></paramdef>
   <paramdef>String <parameter>class</parameter></paramdef>
   <paramdef>String <parameter>defaultp</parameter></paramdef>
   <paramdef>String *<parameter>params</parameter></paramdef>
   <paramdef>Cardinal *<parameter>num_params</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the name to be concatenated with the specified type to form
the resource name of the error message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies the type to be concatenated with the name to form the
resource name of the error message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>class</emphasis>
    </term>
    <listitem>
      <para>
Specifies the resource class of the error message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>defaultp</emphasis>
    </term>
    <listitem>
      <para>
Specifies the default message to use if no error database entry is found.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>params</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to a list of parameters to be substituted in the message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_params</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of entries in <emphasis remap='I'>params</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The specified name can be a general kind of error,
like "invalidParameters" or "invalidWindow",
and the specified type gives extra information
such as the name of the routine in which the error was detected.
Standard
<function>printf</function>
notation is used to substitute the parameters into the message.
</para>

<para>
An error message handler can obtain the error database text for an
error or a warning by calling
<xref linkend='XtAppGetErrorDatabaseText' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppGetErrorDatabaseText'>
<funcprototype>
<funcdef>void <function>XtAppGetErrorDatabaseText</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>String <parameter>name</parameter></paramdef>
   <paramdef>String <parameter>default</parameter></paramdef>
   <paramdef>String <parameter>buffer_return</parameter></paramdef>
   <paramdef>int <parameter>nbytes</parameter></paramdef>
   <paramdef>XrmDatabase <parameter>database</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>name</emphasis>
    </term>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specify the name and type concatenated to form the resource name
of the error message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>class</emphasis>
    </term>
    <listitem>
      <para>
Specifies the resource class of the error message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>default</emphasis>
    </term>
    <listitem>
      <para>
Specifies the default message to use if an error database entry is not found.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>buffer_return</emphasis>
    </term>
    <listitem>
      <para>
Specifies the buffer into which the error message is to be returned.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>nbytes</emphasis>
    </term>
    <listitem>
      <para>
Specifies the size of the buffer in bytes.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>database</emphasis>
    </term>
    <listitem>
      <para>
Specifies the name of the alternative database to be used,
or NULL if the application context's error database is to be used.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The
<xref linkend='XtAppGetErrorDatabaseText' xrefstyle='select: title'/>
returns the appropriate message from the error database
or returns the specified default message if one is not found in the
error database.
To form the full resource name and class when querying the database,
the <emphasis remap='I'>name</emphasis> and <emphasis remap='I'>type</emphasis> are concatenated with a single "."
between them and the <emphasis remap='I'>class</emphasis> is concatenated with itself with a
single "." if it does not already contain a ".".
</para>

<para>
To return the application name and class as passed to
<xref linkend='XtDisplayInitialize' xrefstyle='select: title'/>
for a particular Display, use
<xref linkend='XtGetApplicationNameAndClass' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetApplicationNameAndClass'>
<funcprototype>
<funcdef>void <function>XtGetApplicationNameAndClass</function></funcdef>
    <paramdef>Display* <parameter>display</parameter></paramdef>
    <paramdef>String* <parameter>name_return</parameter></paramdef>
    <paramdef>String* <parameter>class_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies an open display connection that has been initialized with
<xref linkend='XtDisplayInitialize' xrefstyle='select: title'/>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>name_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the application name.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>class_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the application class.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtGetApplicationNameAndClass' xrefstyle='select: title'/>
returns the application name and class passed to
<xref linkend='XtDisplayInitialize' xrefstyle='select: title'/>
for the specified display.  If the display was
never initialized or has been closed, the result is undefined.  The
returned strings are owned by the Intrinsics and must not be modified
or freed by the caller.
</para>

<para>
To register a procedure to be called on fatal error conditions, use
<xref linkend='XtAppSetErrorMsgHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppSetErrorMsgHandler'>
<funcprototype>
<funcdef>XtErrorMsgHandler <function>XtAppSetErrorMsgHandler</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>XtErrorMsgHandler <parameter>msg_handler</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>msg_handler</emphasis>
    </term>
    <listitem>
      <para>
Specifies the new fatal error procedure, which should not return.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtAppSetErrorMsgHandler' xrefstyle='select: title'/>
returns a pointer to the previously
installed high-level fatal error handler.
The default high-level fatal error handler provided by the Intrinsics is named
<function>_XtDefaultErrorMsg</function>
and constructs a string from the error resource database and calls
<xref linkend='XtError' xrefstyle='select: title'/>.
Fatal error message handlers should not return.
If one does,
subsequent Intrinsics behavior is undefined.
</para>

<para>
To call the high-level error handler, use
<xref linkend='XtAppErrorMsg' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppErrorMsg'>
<funcprototype>
<funcdef>void <function>XtAppErrorMsg</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>String <parameter>name</parameter></paramdef>
   <paramdef>String <parameter>type</parameter></paramdef>
   <paramdef>String <parameter>class</parameter></paramdef>
   <paramdef>String <parameter>default</parameter></paramdef>
   <paramdef>String *<parameter>params</parameter></paramdef>
   <paramdef>Cardinal *<parameter>num_params</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the general kind of error.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies the detailed name of the error.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>class</emphasis>
    </term>
    <listitem>
      <para>
Specifies the resource class.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>default</emphasis>
    </term>
    <listitem>
      <para>
Specifies the default message to use if an error database entry is not found.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>params</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to a list of values to be stored in the message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_params</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of entries in <emphasis remap='I'>params</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The Intrinsics internal errors all have class
"XtToolkitError".
</para>

<para>
To register a procedure to be called on nonfatal error conditions, use
<xref linkend='XtAppSetWarningMsgHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppSetWarningMsgHandler'>
<funcprototype>
<funcdef>XtErrorMsgHandler <function>XtAppSetWarningMsgHandler</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>XtErrorMsgHandler <parameter>msg_handler</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>msg_handler</emphasis>
    </term>
    <listitem>
      <para>
Specifies the new nonfatal error procedure, which usually returns.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtAppSetWarningMsgHandler' xrefstyle='select: title'/>
returns a pointer to the previously
installed high-level warning handler.
The default high-level warning handler provided by the Intrinsics is named
<function>_XtDefaultWarningMsg</function>
and constructs a string
from the error resource database and calls
<xref linkend='XtWarning' xrefstyle='select: title'/>.
</para>

<para>
To call the installed high-level warning handler, use
<xref linkend='XtAppWarningMsg' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppWarningMsg'>
<funcprototype>
<funcdef>void <function>XtAppWarningMsg</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>String <parameter>name</parameter></paramdef>
   <paramdef>String <parameter>type</parameter></paramdef>
   <paramdef>String <parameter>class</parameter></paramdef>
   <paramdef>String <parameter>default</parameter></paramdef>
   <paramdef>String *<parameter>params</parameter></paramdef>
   <paramdef>Cardinal *<parameter>num_params</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the general kind of error.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para>
Specifies the detailed name of the error.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>class</emphasis>
    </term>
    <listitem>
      <para>
Specifies the resource class.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>default</emphasis>
    </term>
    <listitem>
      <para>
Specifies the default message to use if an error database entry is not found.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>params</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to a list of values to be stored in the message.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_params</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of entries in <emphasis remap='I'>params</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The Intrinsics internal warnings all have class
"XtToolkitError".
</para>

<para>
The low-level error and warning handler procedure pointers are of type
<xref linkend='XtErrorHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtErrorHandler'>
<funcprototype>
<funcdef>typedef void <function>(*XtErrorHandler)</function></funcdef>
   <paramdef>String <parameter>message</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>message</emphasis>
    </term>
    <listitem>
      <para>
Specifies the error message.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The error handler should display the message string in some appropriate fashion.
</para>

<para>
To register a procedure to be called on fatal error conditions, use
<xref linkend='XtAppSetErrorHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppSetErrorHandler'>
<funcprototype>
<funcdef>XtErrorHandler <function>XtAppSetErrorHandler</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>XtErrorHandler <parameter>handler</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>handler</emphasis>
    </term>
    <listitem>
      <para>
Specifies the new fatal error procedure, which should not return.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtAppSetErrorHandler' xrefstyle='select: title'/>
returns a pointer to the previously installed
low-level fatal error handler.
The default low-level error handler provided by the Intrinsics is
<function>_XtDefaultError</function>.
On POSIX-based systems,
it prints the message to standard error and terminates the application.
Fatal error message handlers should not return.
If one does,
subsequent Intrinsics behavior is undefined.
</para>

<para>
To call the installed fatal error procedure, use
<xref linkend='XtAppError' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppError'>
<funcprototype>
<funcdef>void <function>XtAppError</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>String <parameter>message</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>message</emphasis>
    </term>
    <listitem>
      <para>
Specifies the message to be reported.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
Most programs should use
<xref linkend='XtAppErrorMsg' xrefstyle='select: title'/>,
not
<xref linkend='XtAppError' xrefstyle='select: title'/>,
to provide for customization and internationalization of error messages.
</para>

<para>
To register a procedure to be called on nonfatal error conditions, use
<xref linkend='XtAppSetWarningHandler' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppSetWarningHandler'>
<funcprototype>
<funcdef>XtErrorHandler <function>XtAppSetWarningHandler</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>XtErrorHandler <parameter>handler</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>handler</emphasis>
    </term>
    <listitem>
      <para>
Specifies the new nonfatal error procedure, which usually returns.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtAppSetWarningHandler' xrefstyle='select: title'/>
returns a pointer to the previously installed
low-level warning handler.
The default low-level warning handler provided by the Intrinsics is
<function>_XtDefaultWarning</function>.
On POSIX-based systems,
it prints the message to standard error and returns to the caller.
</para>

<para>
To call the installed nonfatal error procedure, use
<xref linkend='XtAppWarning' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtAppWarning'>
<funcprototype>
<funcdef>void <function>XtAppWarning</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>String <parameter>message</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>message</emphasis>
    </term>
    <listitem>
      <para>
Specifies the nonfatal error message to be reported.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
Most programs should use
<xref linkend='XtAppWarningMsg' xrefstyle='select: title'/>,
not
<xref linkend='XtAppWarning' xrefstyle='select: title'/>,
to provide for customization and internationalization of warning messages.
</para>
</sect1>

<sect1 id="Setting_WM_COLORMAP_WINDOWS">
<title>Setting WM_COLORMAP_WINDOWS</title>
<para>
A client may set the value of the <emphasis role='strong'>WM_COLORMAP_WINDOWS</emphasis>
property on a widget's window by calling
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtSetWMColormapWindows'>
<funcprototype>
<funcdef>void <function>XtSetWMColormapWindows</function></funcdef>
   <paramdef>Widget <parameter>widget</parameter></paramdef>
   <paramdef>Widget* <parameter>list</parameter></paramdef>
   <paramdef>Cardinal <parameter>count</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>widget</emphasis>
    </term>
    <listitem>
      <para>
Specifies the widget on whose window the <emphasis role='strong'>WM_COLORMAP_WINDOWS</emphasis>
property is stored.  Must be of class Core or any subclass thereof.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>list</emphasis>
    </term>
    <listitem>
      <para>
Specifies a list of widgets whose windows are potentially to be
listed in the <emphasis role='strong'>WM_COLORMAP_WINDOWS</emphasis> property.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>count</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of widgets in <emphasis remap='I'>list</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>
returns immediately if <emphasis remap='I'>widget</emphasis> is not realized or if <emphasis remap='I'>count</emphasis> is 0.
Otherwise,
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>
constructs an ordered list of windows
by examining each widget in <emphasis remap='I'>list</emphasis> in turn and
ignoring the widget if it is not realized, or
adding the widget's window to the window list if the widget is realized
and if its colormap resource is different from the colormap
resources of all widgets whose windows are already on the window list.
</para>

<para>
Finally,
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>
stores the resulting window list in the <emphasis role='strong'>WM_COLORMAP_WINDOWS</emphasis>
property on the specified widget's window.
Refer to Section 4.1.8 in the <emphasis remap='I'>Inter-Client Communication Conventions Manual.</emphasis> for details of
the semantics of the <emphasis role='strong'>WM_COLORMAP_WINDOWS</emphasis> property.
</para>
</sect1>
<!--    FIXME: -->
<sect1 id="Finding_File_Names">
<title>Finding File Names</title>
<para>
The Intrinsics provide procedures to look for a file by name, allowing
string substitutions in a list of file specifications.  Two
routines are provided for this:
<xref linkend='XtFindFile' xrefstyle='select: title'/>
and
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>.
<xref linkend='XtFindFile' xrefstyle='select: title'/>
uses an arbitrary set of client-specified substitutions, and
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>
uses a set of standard substitutions corresponding
to the <emphasis remap='I'>X/Open Portability Guide</emphasis> language localization conventions.
Most applications should use
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>.
</para>

<para>
A string substitution is defined by a list of
<function>Substitution</function>
entries.
</para>
<literallayout >
typedef struct {
	char match;
	String substitution;
} SubstitutionRec, *Substitution;
</literallayout>
<para>
File name evaluation is handled in an operating-system-dependent
fashion by an
<xref linkend='XtFilePredicate' xrefstyle='select: title'/>
procedure.
</para>

<funcsynopsis id='XtFilePredicate'>
<funcprototype>
<funcdef>typedef Boolean <function>(*XtFilePredicate)</function></funcdef>
   <paramdef>String <parameter>filename</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>filename</emphasis>
    </term>
    <listitem>
      <para>
Specifies a potential filename.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
A file predicate procedure is called with a string that is
potentially a file name.  It should return
<function>True</function>
if this string specifies a file that is appropriate for the intended use and
<function>False</function>
otherwise.
</para>

<para>
To search for a file using substitutions in a path list, use
<xref linkend='XtFindFile' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtFindFile'>
<funcprototype>
<funcdef>String <function>XtFindFile</function></funcdef>
   <paramdef>String <parameter>path</parameter></paramdef>
   <paramdef>Substitution <parameter>substitutions</parameter></paramdef>
   <paramdef>Cardinal <parameter>num_substitutions</parameter></paramdef>
   <paramdef>XtFilePredicate <parameter>predicate</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>path</emphasis>
    </term>
    <listitem>
      <para>
Specifies a path of file names, including substitution characters.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>substitutions</emphasis>
    </term>
    <listitem>
      <para>
Specifies a list of substitutions to make into the path.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_substitutions</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of substitutions passed in.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>predicate</emphasis>
    </term>
    <listitem>
      <para>
Specifies a procedure called to judge each potential file name, or NULL.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The <emphasis remap='I'>path</emphasis> parameter specifies a string that consists of a series of
potential file names delimited by colons.  Within each name, the
percent character specifies a string substitution selected by the
following character.  The character sequence "%:" specifies an
embedded colon that is not a delimiter; the sequence is replaced by a
single colon.  The character sequence "%%" specifies a percent
character that does not introduce a substitution; the sequence is
replaced by a single percent character.  If a percent character is
followed by any other character,
<xref linkend='XtFindFile' xrefstyle='select: title'/>
looks through the
specified <emphasis remap='I'>substitutions</emphasis> for that character in the <emphasis remap='I'>match</emphasis> field
and, if found,
replaces the percent and match characters with the string in the
corresponding <emphasis remap='I'>substitution</emphasis> field.  A <emphasis remap='I'>substitution</emphasis> field entry of NULL
is equivalent to a pointer to an empty string.  If the operating
system does not interpret multiple embedded name separators in the
path (i.e., "/" in POSIX) the same way as a single separator,
<xref linkend='XtFindFile' xrefstyle='select: title'/>
will collapse multiple separators into a single one after performing
all string substitutions.  Except for collapsing embedded separators,
the contents of the string substitutions are not interpreted by
<xref linkend='XtFindFile' xrefstyle='select: title'/>
and may therefore contain any operating-system-dependent
characters, including additional name separators.  Each resulting
string is passed to the predicate procedure until a string is found for
which the procedure returns
<function>True</function>;
this string is the return value for
<xref linkend='XtFindFile' xrefstyle='select: title'/>.
If no string yields a
<function>True</function>
return from the predicate,
<xref linkend='XtFindFile' xrefstyle='select: title'/>
returns NULL.
</para>

<para>
If the <emphasis remap='I'>predicate</emphasis> parameter is NULL, an internal procedure that checks
if the file exists, is readable, and is not a directory is used.
</para>

<para>
It is the responsibility of the caller to free the returned string using
<xref linkend='XtFree' xrefstyle='select: title'/>
when it is no longer needed.
</para>

<para>
To search for a file using standard substitutions in a path list, use
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtResolvePathname'>
<funcprototype>
<funcdef>String <function>XtResolvePathname</function></funcdef>
   <paramdef>Display *<parameter>display</parameter></paramdef>
   <paramdef>String <parameter>type</parameter></paramdef>
   <paramdef>Substitution <parameter>substitutions</parameter></paramdef>
   <paramdef>Cardinal <parameter>num_substitutions</parameter></paramdef>
   <paramdef>XtFilePredicate <parameter>predicate</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the display to use to find the language for language substitutions.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>type</emphasis>
    </term>
    <listitem>
      <para></para>
      
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>filename</emphasis>
    </term>
    <listitem>
      <para></para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>suffix</emphasis>
    </term>
    <listitem>
      <para>
Specify values to substitute into the path.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>path</emphasis>
    </term>
    <listitem>
      <para>
Specifies the list of file specifications, or NULL.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>substitutions</emphasis>
    </term>
    <listitem>
      <para>
Specifies a list of additional substitutions to make into the path, or NULL.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_substitutions</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of entries in <emphasis remap='I'>substitutions</emphasis>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>predicate</emphasis>
    </term>
    <listitem>
      <para>
Specifies a procedure called to judge each potential file name, or NULL.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The substitutions specified by
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>
are determined from the value of the language string retrieved by
<xref linkend='XtDisplayInitialize' xrefstyle='select: title'/>
for the specified display.
To set the
language for all applications specify "*xnlLanguage: <emphasis remap='I'>lang</emphasis>" in the
resource database.
The format and content of the language string are
implementation-defined.   One suggested syntax is to compose
the language string of three parts;  a  "language  part",  a
"territory  part" and a "codeset part".  The manner in which
this composition is accomplished is implementation-defined,
and the Intrinsics make no interpretation of the parts other
than to use them in substitutions as described below.
</para>


<para>
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>
calls
<xref linkend='XtFindFile' xrefstyle='select: title'/>
with the following substitutions
in addition to any passed by the caller and returns the value returned by
<xref linkend='XtFindFile' xrefstyle='select: title'/>:
</para>
<!-- PROBLEM BELOW HERE -->


<variablelist>
  <varlistentry>
    <term>
%N
    </term>
    <listitem>
      <para>
The value of the <emphasis remap='I'>filename</emphasis> parameter, or the application's
class name if <emphasis remap='I'>filename</emphasis> is NULL.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%T
    </term>
    <listitem>
      <para>
The value of the <emphasis remap='I'>type</emphasis> parameter.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%S
    </term>
    <listitem>
      <para>
The value of the <emphasis remap='I'>suffix</emphasis> parameter.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%L
    </term>
    <listitem>
      <para>
The language string associated with the specified display.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%l
    </term>
    <listitem>
      <para>
The language part of the display's language string.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%t
    </term>
    <listitem>
      <para>
The territory part of the display's language string.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%c
    </term>
    <listitem>
      <para>
The codeset part of the display's language string.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%C
    </term>
    <listitem>
      <para>
The customization string retrieved from the resource
database associated with <emphasis remap='I'>display</emphasis>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
%D
    </term>
    <listitem>
      <para>
The value of the implementation-specific default path.
      </para>
    </listitem>
  </varlistentry>
</variablelist>


<!-- PROBLEM ABOVE HERE -->
<para>
If a path is passed to
<xref linkend='XtResolvePathname' xrefstyle='select: title'/>,
it is passed along to
<xref linkend='XtFindFile' xrefstyle='select: title'/>.
If the <emphasis remap='I'>path</emphasis> argument is NULL, the value of the
<emphasis role='strong'>XFILESEARCHPATH</emphasis>
environment variable is passed to
<xref linkend='XtFindFile' xrefstyle='select: title'/>.
If <emphasis role='strong'>XFILESEARCHPATH</emphasis>
is not defined, an implementation-specific default path is used
that contains at least six entries.  These entries
must contain the following substitutions:
</para>


<!-- OK PAST HERE -->

<literallayout>
1.     %C, %N, %S, %T, %L   or   %C, %N, %S, %T, %l, %t, %c
2.     %C, %N, %S, %T, %l
3.     %C, %N, %S, %T
4.     %N, %S, %T, %L       or   %N, %S, %T, %l, %t, %c
5.     %N, %S, %T, %l
6.     %N, %S, %T
</literallayout>

<para>
The order of these six entries within the path must be as given above.
The order and use of substitutions within a given entry
are implementation-dependent.
If the path begins
with a colon, it is preceded by %N%S.  If the path includes two
adjacent colons, <function>%N%S</function> is inserted between them.
</para>

<para>
The <emphasis remap='I'>type</emphasis> parameter is intended to be a category of files, usually
being translated into a directory in the pathname.  Possible values
might include "app-defaults", "help", and "bitmap".
</para>

<para>
The <emphasis remap='I'>suffix</emphasis> parameter is intended to be appended to the file name.
Possible values might include ".txt", ".dat", and ".bm".
</para>

<para>
A suggested value for the default path on POSIX-based systems is
</para>
<literallayout>
   /usr/lib/X11/%L/%T/%N%C%S:/usr/lib/X11/%l/%T/%N%C%S:\
   /usr/lib/X11/%T/%N%C%S:/usr/lib/X11/%L/%T/%N%S:\
   /usr/lib/X11/%l/%T/%N%S:/usr/lib/X11/%T/%N%S
</literallayout>


<para>
Using this example, if the user has specified a language, it is
used as a subdirectory of /usr/lib/X11 that is searched for other
files.  If the desired file is not found there, the lookup is
tried again using just the language part of the specification.  If the
file is not there, it is looked for in /usr/lib/X11.  The <emphasis remap='I'>type</emphasis>
parameter is used as a subdirectory of the language directory or of
/usr/lib/X11, and <emphasis remap='I'>suffix</emphasis> is appended to the file name.
</para>

<para>
The %D substitution allows the addition of path
elements to the implementation-specific default path, typically to
allow additional directories to be searched without preventing
resources in the system directories from being found.  For example, a
user installing resource files under a directory called "ourdir"
might set
<emphasis role='strong'>XFILESEARCHPATH</emphasis>
to
</para>
<literallayout>
   %D:ourdir/%T/%N%C:ourdir/%T/%N
</literallayout>

<para>
The customization string is obtained by querying the resource database
currently associated with the display (the database returned by
<function>XrmGetDatabase</function>)
for the resource <emphasis remap='I'>application_name</emphasis>.customization, class
<emphasis remap='I'>application_class</emphasis>.Customization, where <emphasis remap='I'>application_name</emphasis>
and <emphasis remap='I'>application_class</emphasis> are the values returned by
<xref linkend='XtGetApplicationNameAndClass' xrefstyle='select: title'/>.
If no value is specified in the database, the empty string is used.
</para>

<para>
It is the responsibility of the caller to free the returned string using
<xref linkend='XtFree' xrefstyle='select: title'/>
when it is no longer needed.
</para>


</sect1>
<!-- END OF FIXME -->
<sect1 id="Hooks_for_External_Agents">
<title>Hooks for External Agents</title>
<para>
Applications may register
functions that are called at a particular control points in the Intrinsics.
These functions are intended to be used to provide notification
of an "X Toolkit event", such as widget creation, to an external agent,
such as an interactive resource editor, drag-and-drop server, or
an aid for physically challenged users.
The control points containing such registration hooks are identified
in a "hook registration" object.
</para>

<para>
To retrieve the hook registration widget, use
<xref linkend='XtHooksOfDisplay' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtHooksOfDisplay'>
<funcprototype>
<funcdef>Widget <function>XtHooksOfDisplay</function></funcdef>
   <paramdef>Display *<parameter>display</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the desired display.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
The class of this object is a private, implementation-dependent
subclass of
<function>Object</function>.
The hook object has no parent.  The resources of this object are
the callback lists for hooks and the read-only resources for getting
a list of parentless shells.  All of the callback lists are initially
empty.  When a display is closed, the hook object associated with it
is destroyed.
</para>

<para>
The following procedures can be called with the hook registration object
as an argument:
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
<xref linkend='XtAddCallback' xrefstyle='select: title'/>,
<xref linkend='XtAddCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtRemoveCallback' xrefstyle='select: title'/>,
<xref linkend='XtRemoveCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtRemoveAllCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtCallCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtHasCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtCallCallbackList' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtClass' xrefstyle='select: title'/>,
<function>XtSuperclass</function>,
<xref linkend='XtIsSubclass' xrefstyle='select: title'/>,
<xref linkend='XtCheckSubclass' xrefstyle='select: title'/>,
<function>XtIsObject</function>,
<function>XtIsRectObj</function>,
<function>XtIsWidget</function>,
<function>XtIsComposite</function>,
<function>XtIsConstraint</function>,
<function>XtIsShell</function>,
<function>XtIsOverrideShell</function>,
<function>XtIsWMShell</function>,
<function>XtIsVendorShell</function>,
<function>XtIsTransientShell</function>,
<function>XtIsToplevelShell</function>,
<function>XtIsApplicationShell</function>,
<function>XtIsSessionShell</function>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtWidgetToApplicationContext' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtName' xrefstyle='select: title'/>,
<function>XtParent</function>,
<xref linkend='XtDisplayOfObject' xrefstyle='select: title'/>,
<xref linkend='XtScreenOfObject' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtSetValues' xrefstyle='select: title'/>,
<xref linkend='XtGetValues' xrefstyle='select: title'/>,
<xref linkend='XtVaSetValues' xrefstyle='select: title'/>,
<xref linkend='XtVaGetValues' xrefstyle='select: title'/>
    </para>
  </listitem>
</itemizedlist>

<sect2 id="Hook_Object_Resources">
<title>Hook Object Resources</title>
<para>
The resource names, classes, and representation types that are specified
in the hook object resource list are:
<informaltable frame='topbot'>
  <?dbfo keep-together="always" ?>
  <tgroup cols='3' align='left' colsep='0' rowsep='0'>
  <colspec colwidth='1.0*' colname='c1'/>
  <colspec colwidth='1.0*' colname='c2'/>
  <colspec colwidth='1.0*' colname='c3'/>
  <thead>
    <row rowsep='1'>
      <entry>Name</entry>
      <entry>Class</entry>
      <entry>Representation</entry>
    </row>
  </thead>
  <tbody>
    <row>
      <entry>XtNcreateHook</entry>
      <entry>XtCCallback</entry>
      <entry>XtRCallback</entry>
    </row>
    <row>
      <entry>XtNchangeHook</entry>
      <entry>XtCCallback</entry>
      <entry>XtRCallback</entry>
    </row>
    <row>
      <entry>XtNconfigureHook</entry>
      <entry>XtCCallback</entry>
      <entry>XtRCallback</entry>
    </row>
    <row>
      <entry>XtNgeometryHook</entry>
      <entry>XtCCallback</entry>
      <entry>XtRCallback</entry>
    </row>
    <row>
      <entry>XtNdestroyHook</entry>
      <entry>XtCCallback</entry>
      <entry>XtRCallback</entry>
    </row>
    <row>
      <entry>XtNshells</entry>
      <entry>XtCReadOnly</entry>
      <entry>XtRWidgetList</entry>
    </row>
    <row>
      <entry>XtNnumShells</entry>
      <entry>XtCReadOnly</entry>
      <entry>XtRCardinal</entry>
    </row>
  </tbody>
  </tgroup>
</informaltable>
</para>

<para>
Descriptions of each of these resources:
</para>

<para>
The XtNcreateHook callback list is called from:
<xref linkend='XtCreateWidget' xrefstyle='select: title'/>,
<xref linkend='XtCreateManagedWidget' xrefstyle='select: title'/>,
<xref linkend='XtCreatePopupShell' xrefstyle='select: title'/>,
<xref linkend='XtAppCreateShell' xrefstyle='select: title'/>,
and their corresponding varargs versions.
</para>

<para>
The <emphasis remap='I'>call_data</emphasis> parameter in a createHook callback may be
cast to type
<function>XtCreateHookData</function>.
</para>
<literallayout >
typedef struct {
	String   type;
	Widget   widget;
	ArgList  args;
	Cardinal num_args;
} XtCreateHookDataRec, *XtCreateHookData;
</literallayout>
<para>
The <emphasis remap='I'>type</emphasis> is set to
<function>XtHcreate</function>,
<emphasis remap='I'>widget</emphasis> is the newly created widget, and <emphasis remap='I'>args</emphasis> and <emphasis remap='I'>num_args</emphasis>
are the arguments passed to the create function. The callbacks are
called before returning from the create function.
</para>

<para>
The XtNchangeHook callback list is called from:
</para>
<itemizedlist spacing='compact'>
  <listitem>
    <para>
<xref linkend='XtSetValues' xrefstyle='select: title'/>,
<xref linkend='XtVaSetValues' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtManageChild' xrefstyle='select: title'/>,
<xref linkend='XtManageChildren' xrefstyle='select: title'/>,
<xref linkend='XtUnmanageChild' xrefstyle='select: title'/>,
<xref linkend='XtUnmanageChildren' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtRealizeWidget' xrefstyle='select: title'/>,
<xref linkend='XtUnrealizeWidget' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtAddCallback' xrefstyle='select: title'/>,
<xref linkend='XtRemoveCallback' xrefstyle='select: title'/>,
<function>XtAddCallbacks,</function>
<xref linkend='XtRemoveCallbacks' xrefstyle='select: title'/>,
<xref linkend='XtRemoveAllCallbacks' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtAugmentTranslations' xrefstyle='select: title'/>,
<xref linkend='XtOverrideTranslations' xrefstyle='select: title'/>,
<xref linkend='XtUninstallTranslations' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtSetKeyboardFocus' xrefstyle='select: title'/>,
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtSetMappedWhenManaged' xrefstyle='select: title'/>,
<xref linkend='XtMapWidget' xrefstyle='select: title'/>,
<xref linkend='XtUnmapWidget' xrefstyle='select: title'/>
    </para>
  </listitem>
  <listitem>
    <para>
<xref linkend='XtPopup' xrefstyle='select: title'/>,
<xref linkend='XtPopupSpringLoaded' xrefstyle='select: title'/>,
<xref linkend='XtPopdown' xrefstyle='select: title'/>
    </para>
  </listitem>
</itemizedlist>

<para>
The <emphasis remap='I'>call_data</emphasis> parameter in a changeHook callback may
be cast to type
<function>XtChangeHookData</function>.
</para>
<literallayout >
typedef struct {
	String  type;
	Widget  widget;
	XtPointer event_data;
	Cardinal num_event_data;
} XtChangeHookDataRec, *XtChangeHookData;
</literallayout>
<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtSetValues' xrefstyle='select: title'/>
or
<xref linkend='XtVaSetValues' xrefstyle='select: title'/>,
<emphasis remap='I'>type</emphasis> is set to
<function>XtHsetValues</function>,
<emphasis remap='I'>widget</emphasis> is the new widget passed to the set_values procedure, and
<emphasis remap='I'>event_data</emphasis> may be cast to type
<function>XtChangeHookSetValuesData</function>.
</para>
<literallayout >
typedef struct {
	Widget   old, req;
	ArgList  args;
	Cardinal num_args;
} XtChangeHookSetValuesDataRec, *XtChangeHookSetValuesData;
</literallayout>
<para>
The <emphasis remap='I'>old</emphasis>, <emphasis remap='I'>req</emphasis>, <emphasis remap='I'>args</emphasis>, and <emphasis remap='I'>num_args</emphasis> are the
parameters passed to the set_values procedure.  The callbacks are called
after the set_values and constraint set_values procedures have been called.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtManageChild' xrefstyle='select: title'/>
or
<xref linkend='XtManageChildren' xrefstyle='select: title'/>,
<emphasis remap='I'>type</emphasis> is set to
<function>XtHmanageChildren</function>,
<emphasis remap='I'>widget</emphasis> is the parent, <emphasis remap='I'>event_data</emphasis> may be cast to type
WidgetList and is the list of children being managed, and
<emphasis remap='I'>num_event_data</emphasis> is the length of the widget list.
The callbacks are called after the children have been managed.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtUnmanageChild' xrefstyle='select: title'/>
or
<xref linkend='XtUnmanageChildren' xrefstyle='select: title'/>,
<emphasis remap='I'>type</emphasis> is set to
<function>XtHunmanageChildren</function>,
<emphasis remap='I'>widget</emphasis> is the parent, <emphasis remap='I'>event_data</emphasis> may be cast to type
WidgetList and is a list of the children being unmanaged, and
<emphasis remap='I'>num_event_data</emphasis> is the length of the widget list.
The callbacks are called after the children have been unmanaged.
</para>

<para>
The changeHook callbacks are called twice as a result of a call to
<xref linkend='XtChangeManagedSet' xrefstyle='select: title'/>,
once after unmanaging and again after managing.
When the callbacks are called the first time, <emphasis remap='I'>type</emphasis> is set to
<function>XtHunmanageSet</function>,
<emphasis remap='I'>widget</emphasis> is the parent, <emphasis remap='I'>event_data</emphasis> may be cast to type
WidgetList and is a list of the children being unmanaged, and
<emphasis remap='I'>num_event_data</emphasis> is the length of the widget list.
When the callbacks are called the second time, the <emphasis remap='I'>type</emphasis> is set to
<function>XtHmanageSet</function>,
<emphasis remap='I'>widget</emphasis> is the parent, <emphasis remap='I'>event_data</emphasis> may be cast to type
WidgetList and is a list of the children being managed, and
<emphasis remap='I'>num_event_data</emphasis> is the length of the widget list.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtRealizeWidget' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHrealizeWidget</function>
and <emphasis remap='I'>widget</emphasis> is the widget being realized.
The callbacks are called after the widget has been realized.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtUnrealizeWidget' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHunrealizeWidget</function>,
and <emphasis remap='I'>widget</emphasis> is the widget being unrealized.
The callbacks are called after the widget has been unrealized.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtAddCallback' xrefstyle='select: title'/>,
<emphasis remap='I'>type</emphasis> is set to
<function>XtHaddCallback</function>,
<emphasis remap='I'>widget</emphasis> is the widget to which the callback is being added, and
<emphasis remap='I'>event_data</emphasis> may be cast to type String and is the name of the
callback being added.
The callbacks are called after the callback has been added to the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtAddCallbacks' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHaddCallbacks</function>,
<emphasis remap='I'>widget</emphasis> is the widget to which the callbacks are being added, and
<emphasis remap='I'>event_data</emphasis> may be cast to type String and is the name of the
callbacks being added.
The callbacks are called after the callbacks have been added to the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtRemoveCallback' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHremoveCallback</function>,
<emphasis remap='I'>widget</emphasis> is the widget from which the callback is being removed, and
<emphasis remap='I'>event_data</emphasis> may be cast to type String and is the name of
the callback being removed.  The callbacks are called after the callback
has been removed from the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtRemoveCallbacks' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHremoveCallbacks</function>,
<emphasis remap='I'>widget</emphasis> is the widget from which the callbacks are being removed, and
<emphasis remap='I'>event_data</emphasis> may be cast to type String and is the name of the
callbacks being removed.  The callbacks are called after the callbacks
have been removed from the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtRemoveAllCallbacks' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHremoveAllCallbacks</function>
and <emphasis remap='I'>widget</emphasis> is the widget from which the callbacks are being removed.
The callbacks are called after the callbacks have been removed from the
widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtAugmentTranslations' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHaugmentTranslations</function>
and <emphasis remap='I'>widget</emphasis> is the widget whose translations are being modified.
The callbacks are called after the widget's translations have been
modified.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtOverrideTranslations' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHoverrideTranslations</function>
and <emphasis remap='I'>widget</emphasis> is the widget whose translations are being modified.
The callbacks are called after the widget's translations have been
modified.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtUninstallTranslations' xrefstyle='select: title'/>,
The <emphasis remap='I'>type</emphasis> is
<function>XtHuninstallTranslations</function>
and <emphasis remap='I'>widget</emphasis> is the widget whose translations are being uninstalled.
The callbacks are called after the widget's translations have been
uninstalled.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtSetKeyboardFocus' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHsetKeyboardFocus</function>
and <emphasis remap='I'>event_data</emphasis> may be cast to type Widget and is the value of
the descendant argument passed to <xref linkend='XtSetKeyboardFocus' xrefstyle='select: title'/>. The
callbacks are called before returning from <xref linkend='XtSetKeyboardFocus' xrefstyle='select: title'/>.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>,
<emphasis remap='I'>type</emphasis> is set to
<function>XtHsetWMColormapWindows</function>,
<emphasis remap='I'>event_data</emphasis> may be cast to type WidgetList and is the value of
the list argument passed to <xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>, and
<emphasis remap='I'>num_event_data</emphasis> is the length of the list. The callbacks are
called before returning from <xref linkend='XtSetWMColormapWindows' xrefstyle='select: title'/>.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtSetMappedWhenManaged' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHsetMappedWhenManaged</function>
and <emphasis remap='I'>event_data</emphasis> may be cast to type Boolean and is the value of
the mapped_when_managed argument passed to <xref linkend='XtSetMappedWhenManaged' xrefstyle='select: title'/>.
The callbacks are called after setting the widget's mapped_when_managed
field and before realizing or unrealizing the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtMapWidget' xrefstyle='select: title'/>,
the <emphasis remap='I'>type </emphasis> is set to
<function>XtHmapWidget</function>
and <emphasis remap='I'>widget</emphasis> is the widget being mapped.
The callbacks are called after mapping the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtUnmapWidget' xrefstyle='select: title'/>,
the <emphasis remap='I'>type </emphasis> is set to
<function>XtHunmapWidget</function>
and <emphasis remap='I'>widget</emphasis> is the widget being unmapped.
The callbacks are called after unmapping the widget.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtPopup' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHpopup</function>,
<emphasis remap='I'>widget</emphasis> is the widget being popped up, and <emphasis remap='I'>event_data</emphasis> may
be cast to type XtGrabKind and is the value of the grab_kind argument
passed to <xref linkend='XtPopup' xrefstyle='select: title'/>.
The callbacks are called before returning from <xref linkend='XtPopup' xrefstyle='select: title'/>.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtPopupSpringLoaded' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHpopupSpringLoaded</function>
and <emphasis remap='I'>widget</emphasis> is the widget being popped up.
The callbacks are called
before returning from <xref linkend='XtPopupSpringLoaded' xrefstyle='select: title'/>.
</para>

<para>
When the changeHook callbacks are called as a result of a call to
<xref linkend='XtPopdown' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is set to
<function>XtHpopdown</function>
and <emphasis remap='I'>widget</emphasis> is the widget being popped down.
The callbacks are called
before returning from <xref linkend='XtPopdown' xrefstyle='select: title'/>.
</para>

<para>
A widget set that exports interfaces that change application state
without employing the Intrinsics library should invoke the change hook
itself.  This is done by:
</para>

<literallayout >
        XtCallCallbacks(XtHooksOfDisplay(dpy), XtNchangeHook, call_data);
</literallayout>
<para>
The XtNconfigureHook callback list is called any time the Intrinsics
move, resize, or configure a widget and when
<xref linkend='XtResizeWindow' xrefstyle='select: title'/>
is called.
</para>

<para>
The <emphasis remap='I'>call_data</emphasis> parameter may be cast to type
<function>XtConfigureHookData.</function>
</para>
<literallayout >
typedef struct {
	String type;
	Widget widget;
	XtGeometryMask changeMask;
	XWindowChanges changes;
} XtConfigureHookDataRec, *XtConfigureHookData;
</literallayout>
<para>
When the configureHook callbacks are called, the <emphasis remap='I'>type</emphasis> is
<function>XtHconfigure</function>,
<emphasis remap='I'>widget</emphasis> is the widget being configured, and <emphasis remap='I'>changeMask</emphasis> and
<emphasis remap='I'>changes</emphasis> reflect the changes made to the widget. The callbacks
are called after changes have been made to the widget.
</para>

<para>
The XtNgeometryHook callback list is called from
<xref linkend='XtMakeGeometryRequest' xrefstyle='select: title'/>
and
<xref linkend='XtMakeResizeRequest' xrefstyle='select: title'/>
once before and once after geometry negotiation occurs.
</para>

<para>
The <emphasis remap='I'>call_data</emphasis> parameter may be cast to type
<function>XtGeometryHookData</function>.
</para>

<literallayout >
typedef struct {
	String type;
	Widget widget;
	XtWidgetGeometry* request;
	XtWidgetGeometry* reply;
	XtGeometryResult result;
} XtGeometryHookDataRec, *XtGeometryHookData;
</literallayout>
<para>
When the geometryHook callbacks are called prior to geometry negotiation,
the <emphasis remap='I'>type</emphasis> is
<function>XtHpreGeometry</function>,
<emphasis remap='I'>widget</emphasis> is the widget for which the request is being made, and
<emphasis remap='I'>request</emphasis> is the requested geometry.
When the geometryHook callbacks
are called after geometry negotiation, the <emphasis remap='I'>type</emphasis> is
<function>XtHpostGeometry</function>,
<emphasis remap='I'>widget</emphasis> is the widget for which the request was made, <emphasis remap='I'>request</emphasis>
is the requested geometry, <emphasis remap='I'>reply</emphasis> is the resulting geometry granted,
and <emphasis remap='I'>result</emphasis> is the value returned from the geometry negotiation.
</para>

<para>
The XtNdestroyHook callback list is called when a widget is destroyed.
The <emphasis remap='I'>call_data parameter</emphasis> may be cast to type
<function>XtDestroyHookData</function>.
</para>
<literallayout >
typedef struct {
	String type;
	Widget widget;
} XtDestroyHookDataRec, *XtDestroyHookData;
</literallayout>
<para>
When the destroyHook callbacks are called as a result of a call to
<xref linkend='XtDestroyWidget' xrefstyle='select: title'/>,
the <emphasis remap='I'>type</emphasis> is
<function>XtHdestroy</function>
and <emphasis remap='I'>widget</emphasis> is the widget being destroyed. The callbacks are
called upon completion of phase one destroy for a widget.
</para>

<para>
The XtNshells and XtnumShells are read-only resources that report a
list of all parentless shell widgets associated with a display.
</para>

<para>
Clients who use these hooks must exercise caution in calling Intrinsics
functions in order to avoid recursion.
</para>
</sect2>

<sect2 id="Querying_Open_Displays">
<title>Querying Open Displays</title>
<para>
To retrieve a list of the Displays associated with an application context,
use
<xref linkend='XtGetDisplays' xrefstyle='select: title'/>.
</para>

<funcsynopsis id='XtGetDisplays'>
<funcprototype>
<funcdef>void <function>XtGetDisplays</function></funcdef>
   <paramdef>XtAppContext <parameter>app_context</parameter></paramdef>
   <paramdef>Display ***<parameter>dpy_return</parameter></paramdef>
   <paramdef>Cardinal *<parameter>num_dpy_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>app_context</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>dpy_return</emphasis>
    </term>
    <listitem>
      <para>
Returns a list of open Display connections in the specified application
context.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>num_dpy_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the count of open Display connections in <emphasis remap='I'>dpy_return</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<xref linkend='XtGetDisplays' xrefstyle='select: title'/> may be used by an external agent to query the
list of open displays that belong to an application context. To free
the list of displays, use
<xref linkend='XtFree' xrefstyle='select: title'/>.
</para>
</sect2>
</sect1>

</chapter>