summaryrefslogtreecommitdiffstats
path: root/x11vnc/x11vnc.1
blob: 82ba1973e830d5b1030bafbdc133d36edd85f113 (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
.\" This file was automatically generated from x11vnc -help output.
.TH X11VNC "1" "January 2006" "x11vnc " "User Commands"
.SH NAME
x11vnc - allow VNC connections to real X11 displays
         version: 0.8, lastmod: 2006-01-11
.SH SYNOPSIS
.B x11vnc
[OPTION]...
.SH DESCRIPTION
.PP
Typical usage is:
.IP
Run this command in a shell on the remote machine "far-host"
with X session you wish to view:
.IP
x11vnc -display :0
.IP
Then run this in another window on the machine you are sitting at:
.IP
vncviewer far-host:0
.PP
Once x11vnc establishes connections with the X11 server and starts listening
as a VNC server it will print out a string: PORT=XXXX where XXXX is typically
5900 (the default VNC server port).  One would next run something like
this on the local machine: "vncviewer hostname:N" where "hostname" is
the name of the machine running x11vnc and N is XXXX - 5900, i.e. usually
"vncviewer hostname:0".
.PP
By default x11vnc will not allow the screen to be shared and it will exit
as soon as the client disconnects.  See \fB-shared\fR and \fB-forever\fR below to override
these protections.  See the FAQ for details how to tunnel the VNC connection
through an encrypted channel such as 
.IR ssh (1).
In brief:
.IP
ssh -L 5900:localhost:5900 far-host 'x11vnc -localhost -display :0'
.IP
vncviewer -encodings 'copyrect tight zrle hextile' localhost:0
.PP
Also, use of a VNC password (-rfbauth or \fB-passwdfile)\fR is strongly recommend.
.PP
For additional info see: http://www.karlrunge.com/x11vnc/
and  http://www.karlrunge.com/x11vnc/#faq
.PP
Rudimentary config file support: if the file $HOME/.x11vncrc exists then each
line in it is treated as a single command line option.  Disable with \fB-norc.\fR
For each option name, the leading character "-" is not required.  E.g. a
line that is either "forever" or "\fB-forever\fR" may be used and are equivalent.
Likewise "wait 100" or "\fB-wait\fR \fI100\fR" are acceptable and equivalent lines.
The "#" character comments out to the end of the line in the usual way
(backslash it for a literal).  Leading and trailing whitespace is trimmed off.
Lines may be continued with a "\\" as the last character of a line (it
becomes a space character).
.PP
.SH OPTIONS

.PP
\fB-display\fR \fIdisp\fR
.IP
X11 server display to connect to, usually :0.  The X
server process must be running on same machine and
support MIT-SHM.  Equivalent to setting the DISPLAY
environment variable to \fIdisp\fR.
.PP
\fB-auth\fR \fIfile\fR
.IP
Set the X authority file to be \fIfile\fR, equivalent to
setting the XAUTHORITY environment variable to \fIfile\fR
before startup.  Same as \fB-xauth\fR file.  See 
.IR Xsecurity (7)
,
.IR xauth (1)
man pages for more info.
.PP
\fB-id\fR \fIwindowid\fR
.IP
Show the window corresponding to \fIwindowid\fR not
the entire display.  New windows like popup menus,
transient toplevels, etc, may not be seen or may be
clipped.  Disabling SaveUnders or BackingStore in the
X server may help show them.  x11vnc may crash if the
window is initially partially obscured, changes size,
is iconified, etc.  Some steps are taken to avoid this
and the \fB-xrandr\fR mechanism is used to track resizes.  Use
.IR xwininfo (1)
to get the window id, or use "\fB-id\fR \fIpick\fR"
to have x11vnc run 
.IR xwininfo (1)
for you and extract
the id.  The \fB-id\fR option is useful for exporting very
simple applications (e.g. the current view on a webcam).
.PP
\fB-sid\fR \fIwindowid\fR
.IP
As \fB-id,\fR but instead of using the window directly it
shifts a root view to it: this shows SaveUnders menus,
etc, although they will be clipped if they extend beyond
the window.
.PP
\fB-clip\fR \fIWxH+X+Y\fR
.IP
Only show the sub-region of the full display that
corresponds to the rectangle with size WxH and offset
+X+Y.  The VNC display has size WxH (i.e. smaller than
the full display).  This also works for \fB-id/-sid\fR mode
where the offset is relative to the upper left corner
of the selected window.
.PP
\fB-flashcmap\fR
.IP
In 8bpp indexed color, let the installed colormap flash
as the pointer moves from window to window (slow).
.PP
\fB-shiftcmap\fR \fIn\fR
.IP
Rare problem, but some 8bpp displays use less than 256
colorcells (e.g. 16-color grayscale, perhaps the other
bits are used for double buffering) *and* also need to
shift the pixels values away from 0, .., ncells.  \fIn\fR
indicates the shift to be applied to the pixel values.
To see the pixel values set DEBUG_CMAP=1 to print out
a colormap histogram.  Example: \fB-shiftcmap\fR 240
.PP
\fB-notruecolor\fR
.IP
For 8bpp displays, force indexed color (i.e. a colormap)
even if it looks like 8bpp TrueColor (rare problem).
.PP
\fB-visual\fR \fIn\fR
.IP
Experimental option: probably does not do what you
think.  It simply *forces* the visual used for the
framebuffer; this may be a bad thing... (e.g. messes
up colors or cause a crash). It is useful for testing
and for some workarounds.  n may be a decimal number,
or 0x hex.  Run 
.IR xdpyinfo (1)
for the values.  One may
also use "TrueColor", etc. see <X11/X.h> for a list.
If the string ends in ":m" then for better or for
worse the visual depth is forced to be m.
.PP
\fB-overlay\fR
.IP
Handle multiple depth visuals on one screen, e.g. 8+24
and 24+8 overlay visuals (the 32 bits per pixel are
packed with 8 for PseudoColor and 24 for TrueColor).
.IP
Currently \fB-overlay\fR only works on Solaris via
.IR XReadScreen (3X11)
and IRIX using 
.IR XReadDisplay (3).
On Solaris there is a problem with image "bleeding"
around transient popup menus (but not for the menu
itself): a workaround is to disable SaveUnders
by passing the "\fB-su\fR" argument to Xsun (in
/etc/dt/config/Xservers).
.IP
Use \fB-overlay\fR as a workaround for situations like these:
Some legacy applications require the default visual to
be 8bpp (8+24), or they will use 8bpp PseudoColor even
when the default visual is depth 24 TrueColor (24+8).
In these cases colors in some windows will be incorrect
in x11vnc unless \fB-overlay\fR is used.  Another use of
\fB-overlay\fR is to enable showing the exact mouse cursor
shape (details below).
.IP
Under \fB-overlay,\fR performance will be somewhat slower
due to the extra image transformations required.
For optimal performance do not use \fB-overlay,\fR but rather
configure the X server so that the default visual is
depth 24 TrueColor and try to have all apps use that
visual (e.g. some apps have \fB-use24\fR or \fB-visual\fR options).
.PP
\fB-overlay_nocursor\fR
.IP
Sets \fB-overlay,\fR but does not try to draw the exact mouse
cursor shape using the overlay mechanism.
.PP
\fB-scale\fR \fIfraction\fR
.IP
Scale the framebuffer by factor \fIfraction\fR.  Values
less than 1 shrink the fb, larger ones expand it.  Note:
image may not be sharp and response may be slower.
If \fIfraction\fR contains a decimal point "." it
is taken as a floating point number, alternatively
the notation "m/n" may be used to denote fractions
exactly, e.g. \fB-scale\fR 2/3
.IP
Scaling Options: can be added after \fIfraction\fR via
":", to supply multiple ":" options use commas.
If you just want a quick, rough scaling without
blending, append ":nb" to \fIfraction\fR (e.g. \fB-scale\fR
1/3:nb).  No blending is the default for 8bpp indexed
color, to force blending for this case use ":fb".
.IP
To disable \fB-scrollcopyrect\fR and \fB-wirecopyrect\fR under
\fB-scale\fR use ":nocr".  If you need to to enable them use
":cr" or specify them explicitly on the command line.
If a slow link is detected, ":nocr" may be applied
automatically.  Default: :cr
.IP
More esoteric options: for compatibility with vncviewers
the scaled width is adjusted to be a multiple of 4:
to disable this use ":n4".  ":in" use interpolation
scheme even when shrinking, ":pad" pad scaled width
and height to be multiples of scaling denominator
(e.g. 3 for 2/3).
.PP
\fB-scale_cursor\fR \fIfrac\fR
.IP
By default if \fB-scale\fR is supplied the cursor shape is
scaled by the same factor.  Depending on your usage,
you may want to scale the cursor independently of the
screen or not at all.  If you specify \fB-scale_cursor\fR
the cursor will be scaled by that factor.  When using
\fB-scale\fR mode to keep the cursor at its "natural" size
use "\fB-scale_cursor\fR \fI1\fR".  Most of the ":" scaling
options apply here as well.
.PP
\fB-viewonly\fR
.IP
All VNC clients can only watch (default off).
.PP
\fB-shared\fR
.IP
VNC display is shared, i.e. more than one viewer can
connect at the same time (default off).
.PP
\fB-once\fR
.IP
Exit after the first successfully connected viewer
disconnects, opposite of \fB-forever.\fR This is the Default.
.PP
\fB-forever\fR
.IP
Keep listening for more connections rather than exiting
as soon as the first client(s) disconnect. Same as \fB-many\fR
.PP
\fB-loop\fR
.IP
Create an outer loop restarting the x11vnc process
whenever it terminates.  \fB-bg\fR and \fB-inetd\fR are ignored in
this mode.  Useful for continuing even if the X server
terminates and restarts (you will need permission to
reconnect of course).   Use, e.g., \fB-loop100\fR to sleep
100 millisecs between restarts, etc.  Default is 2000ms
(i.e. 2 secs)  Use, e.g. \fB-loop300,5\fR to sleep 300 ms
and only loop 5 times.
.PP
\fB-timeout\fR \fIn\fR
.IP
Exit unless a client connects within the first n seconds
after startup.
.PP
\fB-inetd\fR
.IP
Launched by 
.IR inetd (1):
stdio instead of listening socket.
Note: if you are not redirecting stderr to a log file
(via shell 2> or \fB-o\fR option) you MUST also specify the \fB-q\fR
option, otherwise the stderr goes to the viewer which
will cause it to abort.  Specifying both \fB-inetd\fR and \fB-q\fR
and no \fB-o\fR will automatically close the stderr.
.PP
\fB-nofilexfer\fR
.IP
Disable the TightVNC file transfer extension.  (same as
\fB-disablefiletransfer).\fR  Note that when the \fB-viewonly\fR
option is supplied all file transfers are disabled.
Also clients that log in viewonly cannot transfer files.
However, if the remote control mechanism is used to
change the global or per-client viewonly state the
filetransfer permissions will NOT change.
.PP
\fB-http\fR
.IP
Instead of using \fB-httpdir\fR (see below) to specify
where the Java vncviewer applet is, have x11vnc try
to *guess* where the directory is by looking relative
to the program location and in standard locations
(/usr/local/share/x11vnc/classes, etc).
.PP
\fB-connect\fR \fIstring\fR
.IP
For use with "vncviewer -listen" reverse connections.
If \fIstring\fR has the form "host" or "host:port"
the connection is made once at startup.  Use commas
for a list of host's and host:port's.
.IP
If \fIstring\fR contains "/" it is instead interpreted
as a file to periodically check for new hosts.
The first line is read and then the file is truncated.
Be careful for this usage mode if x11vnc is running as
root (e.g. via 
.IR gdm (1)
, etc).
.PP
\fB-vncconnect,\fR \fB-novncconnect\fR
.IP
Monitor the VNC_CONNECT X property set by the standard
VNC program 
.IR vncconnect (1).
When the property is
set to "host" or "host:port" establish a reverse
connection.  Using 
.IR xprop (1)
instead of vncconnect may
work (see the FAQ).  The \fB-remote\fR control mechanism also
uses this VNC_CONNECT channel.  Default: \fB-vncconnect\fR
.PP
\fB-allow\fR \fIhost1[,host2..]\fR
.IP
Only allow client connections from hosts matching
the comma separated list of hostnames or IP addresses.
Can also be a numerical IP prefix, e.g. "192.168.100."
to match a simple subnet, for more control build
libvncserver with libwrap support (See the FAQ).  If the
list contains a "/" it instead is a interpreted as a
file containing addresses or prefixes that is re-read
each time a new client connects.  Lines can be commented
out with the "#" character in the usual way.
.PP
\fB-localhost\fR
.IP
Same as "\fB-allow\fR \fI127.0.0.1\fR".
.IP
Note: if you want to restrict which network interface
x11vnc listens on, see the \fB-listen\fR option below.
E.g. "\fB-listen\fR \fIlocalhost\fR" or "\fB-listen\fR \fI192.168.3.21\fR".
As a special case, the option "\fB-localhost\fR" implies
"\fB-listen\fR \fIlocalhost\fR".
.IP
For non-localhost \fB-listen\fR usage, if you use the remote
control mechanism (-R) to change the \fB-listen\fR interface
you may need to manually adjust the \fB-allow\fR list (and
vice versa) to avoid situations where no connections
(or too many) are allowed.
.PP
\fB-nolookup\fR
.IP
Do not use gethostbyname() or gethostbyaddr() to look up
host names or IP numbers.  Use this if name resolution
is incorrectly set up and leads to long pauses as name
lookups time out, etc.
.PP
\fB-input\fR \fIstring\fR
.IP
Fine tuning of allowed user input.  If \fIstring\fR does
not contain a comma "," the tuning applies only to
normal clients.  Otherwise the part before "," is
for normal clients and the part after for view-only
clients.  "K" is for Keystroke input, "M" for
Mouse-motion input, and "B" for Button-click input.
Their presence in the string enables that type of input.
E.g. "\fB-input\fR \fIM\fR" means normal users can only move
the mouse and  "\fB-input\fR \fIKMB,M\fR" lets normal users do
anything and enables view-only users to move the mouse.
This option is ignored when a global \fB-viewonly\fR is in
effect (all input is discarded in that case).
.PP
\fB-viewpasswd\fR \fIstring\fR
.IP
Supply a 2nd password for view-only logins.  The \fB-passwd\fR
(full-access) password must also be supplied.
.PP
\fB-passwdfile\fR \fIfilename\fR
.IP
Specify the libvncserver password via the first line
of the file \fIfilename\fR (instead of via \fB-passwd\fR on
the command line where others might see it via 
.IR ps (1)
).
See below for how to supply multiple passwords.
.IP
If the filename is prefixed with "rm:" it will be
removed after being read.  Perhaps this is useful in
limiting the readability of the file.  In general,
the password file should not be readable by untrusted
users (BTW: neither should the VNC \fB-rfbauth\fR file:
it is NOT encrypted).
.IP
If the filename is prefixed with "read:" it will
periodically be checked for changes and reread.
.IP
Note that only the first 8 characters of a password
are used.
.IP
If multiple non-blank lines exist in the file they are
all taken as valid passwords.  Blank lines are ignored.
Password lines may be "commented out" (ignored) if
they begin with the charactor "#" or the line contains
the string "__SKIP__".  Lines may be annotated by use
of the "__COMM__" string: from it to the end of the
line is ignored.  An empty password may be specified
via the "__EMPTY__" string on a line by itself (note
your viewer might not accept empty passwords).
.IP
If the string "__BEGIN_VIEWONLY__" appears on a
line by itself, the remaining passwords are used for
viewonly access.  For compatibility, as a special case
if the file contains only two password lines the 2nd
one is automatically taken as the viewonly password.
Otherwise the "__BEGIN_VIEWONLY__" token must be
used to have viewonly passwords.  (tip: make the 3rd
and last line be "__BEGIN_VIEWONLY__" to have 2
full-access passwords)
.PP
\fB-nopw\fR
.IP
Disable the big warning message when you use x11vnc
without some sort of password.
.PP
\fB-storepasswd\fR \fIpass\fR \fIfile\fR
.IP
Store password \fIpass\fR as the VNC password in the
file \fIfile\fR.  Once the password is stored the
program exits.  Use the password via "\fB-rfbauth\fR \fIfile\fR"
.PP
\fB-accept\fR \fIstring\fR
.IP
Run a command (possibly to prompt the user at the
X11 display) to decide whether an incoming client
should be allowed to connect or not.  \fIstring\fR is
an external command run via 
.IR system (3)
or some special
cases described below.  Be sure to quote \fIstring\fR
if it contains spaces, shell characters, etc.  If the
external command returns 0 the client is accepted,
otherwise the client is rejected.  See below for an
extension to accept a client view-only.
.IP
If x11vnc is running as root (say from 
.IR inetd (1)
or from
display managers 
.IR xdm (1)
, 
.IR gdm (1)
, etc), think about the
security implications carefully before supplying this
option (likewise for the \fB-gone\fR option).
.IP
Environment: The RFB_CLIENT_IP environment variable will
be set to the incoming client IP number and the port
in RFB_CLIENT_PORT (or -1 if unavailable).  Similarly,
RFB_SERVER_IP and RFB_SERVER_PORT (the x11vnc side
of the connection), are set to allow identification
of the tcp virtual circuit.  The x11vnc process
id will be in RFB_X11VNC_PID, a client id number in
RFB_CLIENT_ID, and the number of other connected clients
in RFB_CLIENT_COUNT.  RFB_MODE will be "accept".
RFB_STATE will be PROTOCOL_VERSION, SECURITY_TYPE,
AUTHENTICATION, INITIALISATION, NORMAL, or UNKNOWN
indicating up to which state the client has acheived.
RFB_LOGIN_VIEWONLY will be 0, 1, or -1 (unknown).
RFB_USERNAME, RFB_LOGIN_TIME, and RFB_CURRENT_TIME may
also be set.
.IP
If \fIstring\fR is "popup" then a builtin popup window
is used.  The popup will time out after 120 seconds,
use "popup:N" to modify the timeout to N seconds
(use 0 for no timeout).
.IP
If \fIstring\fR is "xmessage" then an 
.IR xmessage (1)
invocation is used for the command.  xmessage must be
installed on the machine for this to work.
.IP
Both "popup" and "xmessage" will present an option
for accepting the client "View-Only" (the client
can only watch).  This option will not be presented if
\fB-viewonly\fR has been specified, in which case the entire
display is view only.
.IP
If the user supplied command is prefixed with something
like "yes:0,no:*,view:3 mycommand ..." then this
associates the numerical command return code with
the actions: accept, reject, and accept-view-only,
respectively.  Use "*" instead of a number to indicate
the default action (in case the command returns an
unexpected value).  E.g. "no:*" is a good choice.
.IP
Note that x11vnc blocks while the external command
or popup is running (other clients may see no updates
during this period).  So a person sitting a the physical
display is needed to respond to an popup prompt. (use
a 2nd x11vnc if you lock yourself out).
.IP
More \fB-accept\fR tricks: use "popupmouse" to only allow
mouse clicks in the builtin popup to be recognized.
Similarly use "popupkey" to only recognize
keystroke responses.  These are to help avoid the
user accidentally accepting a client by typing or
clicking. All 3 of the popup keywords can be followed
by +N+M to supply a position for the popup window.
The default is to center the popup window.
.PP
\fB-afteraccept\fR \fIstring\fR
.IP
As \fB-accept,\fR except to run a user supplied command after
a client has been accepted and authenticated. RFB_MODE
will be set to "afteraccept" and the other RFB_*
variables are as in \fB-accept.\fR  Unlike \fB-accept,\fR the
command return code is not interpreted by x11vnc.
Example: \fB-afteraccept\fR 'killall xlock &'
.PP
\fB-gone\fR \fIstring\fR
.IP
As \fB-accept,\fR except to run a user supplied command when
a client goes away (disconnects).  RFB_MODE will be
set to "gone" and the other RFB_* variables are as
in \fB-accept.\fR  Unlike \fB-accept,\fR the command return code
is not interpreted by x11vnc.  Example: \fB-gone\fR 'xlock &'
.PP
\fB-users\fR \fIlist\fR
.IP
If x11vnc is started as root (say from 
.IR inetd (1)
or from
display managers 
.IR xdm (1)
, 
.IR gdm (1)
, etc), then as soon
as possible after connections to the X display are
established try to switch to one of the users in the
comma separated \fIlist\fR.  If x11vnc is not running as
root this option is ignored.
.IP
Why use this option?  In general it is not needed since
x11vnc is already connected to the X display and can
perform its primary functions.  The option was added
to make some of the *external* utility commands x11vnc
occasionally runs work properly.  In particular under
GNOME and KDE to implement the "\fB-solid\fR \fIcolor\fR" feature
external commands (gconftool-2 and dcop) must be run
as the user owning the desktop session.  Since this
option switches userid it also affects the userid used
to run the processes for the \fB-accept\fR and \fB-gone\fR options.
It also affects the ability to read files for options
such as \fB-connect,\fR \fB-allow,\fR and \fB-remap.\fR  Note that the
\fB-connect\fR file is also sometimes written to.
.IP
So be careful with this option since in many situations
its use can decrease security.
.IP
The switch to a user will only take place if the
display can still be successfully opened as that user
(this is primarily to try to guess the actual owner
of the session). Example: "\fB-users\fR \fIfred,wilma,betty\fR".
Note that a malicious user "barney" by quickly using
"xhost +" when logging in may get x11vnc to switch
to user "fred".  What happens next?
.IP
Under display managers it may be a long time before
the switch succeeds (i.e. a user logs in).  To make
it switch immediately regardless if the display
can be reopened prefix the username with the "+"
character. E.g. "\fB-users\fR \fI+bob\fR" or "\fB-users\fR \fI+nobody\fR".
The latter (i.e. switching immediately to user
"nobody") is probably the only use of this option
that increases security.
.IP
To immediately switch to a user *before* connections
to the X display are made or any files opened use the
"=" character: "\fB-users\fR \fI=bob\fR".  That user needs to
be able to open the X display of course.
.IP
The special user "guess=" means to examine the utmpx
database (see 
.IR who (1)
) looking for a user attached to
the display number (from DISPLAY or \fB-display\fR option)
and try him/her.  To limit the list of guesses, use:
"\fB-users\fR \fIguess=bob,betty\fR".
.IP
Even more sinister is the special user "lurk=" that
means to try to guess the DISPLAY from the utmpx login
database as well.  So it "lurks" waiting for anyone
to log into an X session and then connects to it.
Specify a list of users after the = to limit which
users will be tried.  To enable a different searching
mode, if the first user in the list is something like
":0" or ":0-2" that indicates a range of DISPLAY
numbers that will be tried (regardless of whether
they are in the utmpx database) for all users that
are logged in.  Examples: "\fB-users\fR \fIlurk=\fR" and also
"\fB-users\fR \fIlurk=:0-1,bob,mary\fR"
.IP
Be especially careful using the "guess=" and "lurk="
modes.  They are not recommended for use on machines
with untrustworthy local users.
.PP
\fB-noshm\fR
.IP
Do not use the MIT-SHM extension for the polling.
Remote displays can be polled this way: be careful this
can use large amounts of network bandwidth.  This is
also of use if the local machine has a limited number
of shm segments and \fB-onetile\fR is not sufficient.
.PP
\fB-flipbyteorder\fR
.IP
Sometimes needed if remotely polled host has different
endianness.  Ignored unless \fB-noshm\fR is set.
.PP
\fB-onetile\fR
.IP
Do not use the new copy_tiles() framebuffer mechanism,
just use 1 shm tile for polling.  Limits shm segments
used to 3.
.PP
\fB-solid\fR \fI[color]\fR
.IP
To improve performance, when VNC clients are connected
try to change the desktop background to a solid color.
The [color] is optional: the default color is "cyan4".
For a different one specify the X color (rgb.txt name,
e.g. "darkblue" or numerical "#RRGGBB").
.IP
Currently this option only works on GNOME, KDE, CDE,
and classic X (i.e. with the background image on the
root window).  The "gconftool-2" and "dcop" external
commands are run for GNOME and KDE respectively.
Other desktops won't work, e.g. Xfce (send us the
corresponding commands if you find them).  If x11vnc is
running as root (
.IR inetd (1)
or 
.IR gdm (1)
), the \fB-users\fR option
may be needed for GNOME and KDE.  If x11vnc guesses
your desktop incorrectly, you can force it by prefixing
color with "gnome:", "kde:", "cde:" or "root:".
.PP
\fB-blackout\fR \fIstring\fR
.IP
Black out rectangles on the screen. \fIstring\fR is a
comma separated list of WxH+X+Y type geometries for
each rectangle.  If one of the items on the list is the
string "noptr" the mouse pointer will not be allowed
to go into a blacked out region.
.PP
\fB-xinerama\fR
.IP
If your screen is composed of multiple monitors
glued together via XINERAMA, and that screen is
not a rectangle this option will try to guess the
areas to black out (if your system has libXinerama).
.IP
In general, we have noticed on XINERAMA displays you
may need to use the "\fB-xwarppointer\fR" option if the mouse
pointer misbehaves.
.PP
\fB-xtrap\fR
.IP
Use the DEC-XTRAP extension for keystroke and mouse
input insertion.  For use on legacy systems, e.g. X11R5,
running an incomplete or missing XTEST extension.
By default DEC-XTRAP will be used if XTEST server grab
control is missing, use \fB-xtrap\fR to do the keystroke and
mouse insertion via DEC-XTRAP as well.
.PP
\fB-xrandr\fR \fI[mode]\fR
.IP
If the display supports the XRANDR (X Resize, Rotate
and Reflection) extension, and you expect XRANDR events
to occur to the display while x11vnc is running, this
options indicates x11vnc should try to respond to
them (as opposed to simply crashing by assuming the
old screen size).  See the 
.IR xrandr (1)
manpage and run
\'xrandr \fB-q'\fR for more info.  [mode] is optional and
described below.
.IP
Since watching for XRANDR events and trapping errors
increases polling overhead, only use this option if
XRANDR changes are expected.  For example on a rotatable
screen PDA or laptop, or using a XRANDR-aware Desktop
where you resize often.  It is best to be viewing with a
vncviewer that supports the NewFBSize encoding, since it
knows how to react to screen size changes.  Otherwise,
libvncserver tries to do so something reasonable for
viewers that cannot do this (portions of the screen
may be clipped, unused, etc).
.IP
"mode" defaults to "resize", which means create a
new, resized, framebuffer and hope all viewers can cope
with the change.  "newfbsize" means first disconnect
all viewers that do not support the NewFBSize VNC
encoding, and then resize the framebuffer.  "exit"
means disconnect all viewer clients, and then terminate
x11vnc.
.PP
\fB-padgeom\fR \fIWxH\fR
.IP
Whenever a new vncviewer connects, the framebuffer is
replaced with a fake, solid black one of geometry WxH.
Shortly afterwards the framebuffer is replaced with the
real one.  This is intended for use with vncviewers
that do not support NewFBSize and one wants to make
sure the initial viewer geometry will be big enough
to handle all subsequent resizes (e.g. under \fB-xrandr,\fR
\fB-remote\fR id:windowid, rescaling, etc.)
.PP
\fB-o\fR \fIlogfile\fR
.IP
Write stderr messages to file \fIlogfile\fR instead of
to the terminal.  Same as "\fB-logfile\fR \fIfile\fR".  To append
to the file use "\fB-oa\fR \fIfile\fR" or "\fB-logappend\fR \fIfile\fR".
.PP
\fB-flag\fR \fIfile\fR
.IP
Write the "PORT=NNNN" (e.g. PORT=5900) string to
\fIfile\fR in addition to stdout.  This option could be
useful by wrapper script to detect when x11vnc is ready.
.PP
\fB-rc\fR \fIfilename\fR
.IP
Use \fIfilename\fR instead of $HOME/.x11vncrc for rc file.
.PP
\fB-norc\fR
.IP
Do not process any .x11vncrc file for options.
.PP
\fB-h,\fR \fB-help\fR
.IP
Print this help text.
-?, \fB-opts\fR              Only list the x11vnc options.
.PP
\fB-V,\fR \fB-version\fR
.IP
Print program version and last modification date.
.PP
\fB-dbg\fR
.IP
Instead of exiting after cleaning up, run a simple
"debug crash shell" when fatal errors are trapped.
.PP
\fB-q\fR
.IP
Be quiet by printing less informational output to
stderr.  Same as \fB-quiet.\fR
.PP
\fB-bg\fR
.IP
Go into the background after screen setup.  Messages to
stderr are lost unless \fB-o\fR logfile is used.  Something
like this could be useful in a script:
.IP
port=`ssh $host "x11vnc -display :0 -bg" | grep PORT`
.IP
port=`echo "$port" | sed -e 's/PORT=//'`
.IP
port=`expr $port - 5900`
.IP
vncviewer $host:$port
.PP
\fB-modtweak,\fR \fB-nomodtweak\fR
.IP
Option \fB-modtweak\fR automatically tries to adjust the AltGr
and Shift modifiers for differing language keyboards
between client and host.  Otherwise, only a single key
press/release of a Keycode is simulated (i.e. ignoring
the state of the modifiers: this usually works for
identical keyboards).  Also useful in resolving cases
where a Keysym is bound to multiple keys (e.g. "<" + ">"
and "," + "<" keys).  Default: \fB-modtweak\fR
.PP
\fB-xkb,\fR \fB-noxkb\fR
.IP
When in modtweak mode, use the XKEYBOARD extension (if
the X display supports it) to do the modifier tweaking.
This is powerful and should be tried if there are still
keymapping problems when using \fB-modtweak\fR by itself.
The default is to check whether some common keysyms,
e.g. !, @, [, are only accessible via \fB-xkb\fR mode and if
so then automatically enable the mode.  To disable this
automatic detection use \fB-noxkb.\fR
.PP
\fB-skip_keycodes\fR \fIstring\fR
.IP
Ignore the comma separated list of decimal keycodes.
Perhaps these are keycodes not on your keyboard but
your X server thinks exist.  Currently only applies
to \fB-xkb\fR mode.  Use this option to help x11vnc in the
reverse problem it tries to solve: Keysym -> Keycode(s)
when ambiguities exist (more than one Keycode per
Keysym).  Run 'xmodmap \fB-pk'\fR to see your keymapping.
Example: "\fB-skip_keycodes\fR \fI94,114\fR"
.PP
\fB-sloppy_keys\fR
.IP
Experimental option that tries to correct some
"sloppy" key behavior.  E.g. if at the viewer you
press Shift+Key but then release the Shift before
Key that could give rise to extra unwanted characters
(usually only between keyboards of different languages).
Only use this option if you observe problems with
some keystrokes.
.PP
\fB-skip_dups,\fR \fB-noskip_dups\fR
.IP
Some VNC viewers send impossible repeated key events,
e.g. key-down, key-down, key-up, key-up all for the same
key, or 20 downs in a row for the same modifier key!
Setting \fB-skip_dups\fR means to skip these duplicates and
just process the first event. Note: some VNC viewers
assume they can send down's without the corresponding
up's and so you should not set this option for
these viewers (symptom: some keys do not autorepeat)
Default: \fB-noskip_dups\fR
.PP
\fB-add_keysyms,\fR \fB-noadd_keysyms\fR
.IP
If a Keysym is received from a VNC viewer and that
Keysym does not exist in the X server, then add the
Keysym to the X server's keyboard mapping on an unused
key.  Added Keysyms will be removed periodically and
also when x11vnc exits.  Default: \fB-add_keysyms\fR
.PP
\fB-clear_mods\fR
.IP
At startup and exit clear the modifier keys by sending
KeyRelease for each one. The Lock modifiers are skipped.
Used to clear the state if the display was accidentally
left with any pressed down.
.PP
\fB-clear_keys\fR
.IP
As \fB-clear_mods,\fR except try to release any pressed key.
Note that this option and \fB-clear_mods\fR can interfere
with a person typing at the physical keyboard.
.PP
\fB-remap\fR \fIstring\fR
.IP
Read Keysym remappings from file named \fIstring\fR.
Format is one pair of Keysyms per line (can be name
or hex value) separated by a space.  If no file named
\fIstring\fR exists, it is instead interpreted as this
form: key1-key2,key3-key4,...  See <X11/keysymdef.h>
header file for a list of Keysym names, or use 
.IR xev (1).
To map a key to a button click, use the fake Keysyms
"Button1", ..., etc. E.g: "\fB-remap\fR \fISuper_R-Button2\fR"
(useful for pasting on a laptop)
.IP
Dead keys: "dead" (or silent, mute) keys are keys that
do not produce a character but must be followed by a 2nd
keystroke.  This is often used for accenting characters,
e.g. to put "`" on top of "a" by pressing the dead
key and then "a".  Note that this interpretation
is not part of core X11, it is up to the toolkit or
application to decide how to react to the sequence.
The X11 names for these keysyms are "dead_grave",
"dead_acute", etc.  However some VNC viewers send the
keysyms "grave", "acute" instead thereby disabling
the accenting.  To work around this \fB-remap\fR can be used.
For example "\fB-remap\fR \fIgrave-dead_grave,acute-dead_acute\fR"
.IP
As a convenience, "\fB-remap\fR \fIDEAD\fR" applies these remaps:
.IP
      g     grave-dead_grave
      a     acute-dead_acute
      c     asciicircum-dead_circumflex
      t     asciitilde-dead_tilde
      m     macron-dead_macron
      b     breve-dead_breve
      D     abovedot-dead_abovedot
      d     diaeresis-dead_diaeresis
      o     degree-dead_abovering
      A     doubleacute-dead_doubleacute
      r     caron-dead_caron
      e     cedilla-dead_cedilla
.IP
.IP
If you just want a subset use the first letter
label, e.g. "\fB-remap\fR \fIDEAD=ga\fR" to get the first two.
Additional remaps may also be supplied via commas,
e.g.  "\fB-remap\fR \fIDEAD=ga,Super_R-Button2\fR".  Finally,
"DEAD=missing" means to apply all of the above as
long as the left hand member is not already in the
X11 keymap.
.PP
\fB-norepeat,\fR \fB-repeat\fR
.IP
Option \fB-norepeat\fR disables X server key auto repeat when
VNC clients are connected and VNC keyboard input is
not idle for more than 5 minutes.  This works around a
repeating keystrokes bug (triggered by long processing
delays between key down and key up client events: either
from large screen changes or high latency).
Default: \fB-norepeat\fR
.IP
Note: your VNC viewer side will likely do autorepeating,
so this is no loss unless someone is simultaneously at
the real X display.
.IP
Use "\fB-norepeat\fR \fIN\fR" to set how many times norepeat will
be reset if something else (e.g. X session manager)
undoes it.  The default is 2.  Use a negative value
for unlimited resets.
.PP
\fB-nofb\fR
.IP
Ignore video framebuffer: only process keyboard and
pointer.  Intended for use with Win2VNC and x2vnc
dual-monitor setups.
.PP
\fB-nobell\fR
.IP
Do not watch for XBell events. (no beeps will be heard)
Note: XBell monitoring requires the XKEYBOARD extension.
.PP
\fB-nosel\fR
.IP
Do not manage exchange of X selection/cutbuffer between
VNC viewers and the X server.
.PP
\fB-noprimary\fR
.IP
Do not poll the PRIMARY selection for changes to send
back to clients.  (PRIMARY is still set on received
changes, however).
.PP
\fB-seldir\fR \fIstring\fR
.IP
If direction string is "send", only send the selection
to viewers, and if it is "recv" only receive it from
viewers.  To work around apps setting the selection
too frequently and messing up the other end.  You can
actually supply a comma separated list of directions,
including "debug" to turn on debugging output.
.PP
\fB-cursor\fR \fI[mode],\fR \fB-nocursor\fR
.IP
Sets how the pointer cursor shape (little icon at the
mouse pointer) should be handled.  The "mode" string
is optional and is described below.  The default
is to show some sort of cursor shape(s).  How this
is done depends on the VNC viewer and the X server.
Use \fB-nocursor\fR to disable cursor shapes completely.
.IP
Some VNC viewers support the TightVNC CursorPosUpdates
and CursorShapeUpdates extensions (cuts down on
network traffic by not having to send the cursor image
every time the pointer is moved), in which case these
extensions are used (see \fB-nocursorshape\fR and \fB-nocursorpos\fR
below to disable).  For other viewers the cursor shape
is written directly to the framebuffer every time the
pointer is moved or changed and gets sent along with
the other framebuffer updates.  In this case, there
will be some lag between the vnc viewer pointer and
the remote cursor position.
.IP
If the X display supports retrieving the cursor shape
information from the X server, then the default is
to use that mode.  On Solaris this can be done with
the SUN_OVL extension using \fB-overlay\fR (see also the
\fB-overlay_nocursor\fR option).  A similar overlay scheme
is used on IRIX.  Xorg (e.g. Linux) and recent Solaris
Xsun servers support the XFIXES extension to retrieve
the exact cursor shape from the X server.  If XFIXES
is present it is preferred over Overlay and is used by
default (see \fB-noxfixes\fR below).  This can be disabled
with \fB-nocursor,\fR and also some values of the "mode"
option below.
.IP
Note that under XFIXES cursors with transparency (alpha
channel) will usually not be exactly represented and one
may find Overlay preferable.  See also the \fB-alphacut\fR
and \fB-alphafrac\fR options below as fudge factors to try
to improve the situation for cursors with transparency
for a given theme.
.IP
The "mode" string can be used to fine-tune the
displaying of cursor shapes.  It can be used the
following ways:
.IP
"\fB-cursor\fR \fIarrow\fR" - just show the standard arrow
nothing more or nothing less.
.IP
"\fB-cursor\fR \fInone\fR" - same as "\fB-nocursor\fR"
.IP
"\fB-cursor\fR \fIX\fR" - when the cursor appears to be on the
root window, draw the familiar X shape.  Some desktops
such as GNOME cover up the root window completely,
and so this will not work, try "X1", etc, to try to
shift the tree depth.  On high latency links or slow
machines there will be a time lag between expected and
the actual cursor shape.
.IP
"\fB-cursor\fR \fIsome\fR" - like "X" but use additional
heuristics to try to guess if the window should have
a windowmanager-like resizer cursor or a text input
I-beam cursor.  This is a complete hack, but may be
useful in some situations because it provides a little
more feedback about the cursor shape.
.IP
"\fB-cursor\fR \fImost\fR" - try to show as many cursors as
possible.  Often this will only be the same as "some"
unless the display has overlay visuals or XFIXES
extensions available.  On Solaris and IRIX if XFIXES
is not available, \fB-overlay\fR mode will be attempted.
.PP
\fB-arrow\fR \fIn\fR
.IP
Choose an alternate "arrow" cursor from a set of
some common ones.  n can be 1 to 6.  Default is: 1
Ignored when in XFIXES cursor-grabbing mode.
.PP
\fB-noxfixes\fR
.IP
Do not use the XFIXES extension to draw the exact cursor
shape even if it is available.
.PP
\fB-alphacut\fR \fIn\fR
.IP
When using the XFIXES extension for the cursor shape,
cursors with transparency will not usually be displayed
exactly (but opaque ones will).  This option sets n as
a cutoff for cursors that have transparency ("alpha
channel" with values ranging from 0 to 255) Any cursor
pixel with alpha value less than n becomes completely
transparent.  Otherwise the pixel is completely opaque.
Default 240
.PP
\fB-alphafrac\fR \fIfraction\fR
.IP
With the threshold in \fB-alphacut\fR some cursors will become
almost completely transparent because their alpha values
are not high enough.  For those cursors adjust the
alpha threshold until fraction of the non-zero alpha
channel pixels become opaque.  Default 0.33
.PP
\fB-alpharemove\fR
.IP
By default, XFIXES cursors pixels with transparency have
the alpha factor multiplied into the RGB color values
(i.e. that corresponding to blending the cursor with a
black background).  Specify this option to remove the
alpha factor. (useful for light colored semi-transparent
cursors).
.PP
\fB-noalphablend\fR
.IP
In XFIXES mode do not send cursor alpha channel data
to libvncserver.  The default is to send it.  The
alphablend effect will only be visible in \fB-nocursorshape\fR
mode or for clients with cursorshapeupdates turned
off. (However there is a hack for 32bpp with depth 24,
it uses the extra 8 bits to store cursor transparency
for use with a hacked vncviewer that applies the
transparency locally.  See the FAQ for more info).
.PP
\fB-nocursorshape\fR
.IP
Do not use the TightVNC CursorShapeUpdates extension
even if clients support it.  See \fB-cursor\fR above.
.PP
\fB-cursorpos,\fR \fB-nocursorpos\fR
.IP
Option \fB-cursorpos\fR enables sending the X cursor position
back to all vnc clients that support the TightVNC
CursorPosUpdates extension.  Other clients will be able
to see the pointer motions. Default: \fB-cursorpos\fR
.PP
\fB-xwarppointer\fR
.IP
Move the pointer with 
.IR XWarpPointer (3X)
instead of
the XTEST extension.  Use this as a workaround
if the pointer motion behaves incorrectly, e.g.
on touchscreens or other non-standard setups.
Also sometimes needed on XINERAMA displays.
.PP
\fB-buttonmap\fR \fIstring\fR
.IP
String to remap mouse buttons.  Format: IJK-LMN, this
maps buttons I -> L, etc., e.g.  \fB-buttonmap\fR 13-31
.IP
Button presses can also be mapped to keystrokes: replace
a button digit on the right of the dash with :<sym>:
or :<sym1>+<sym2>: etc. for multiple keys. For example,
if the viewing machine has a mouse-wheel (buttons 4 5)
but the x11vnc side does not, these will do scrolls:
.IP
\fB-buttonmap\fR 12345-123:Prior::Next:
.IP
\fB-buttonmap\fR 12345-123:Up+Up+Up::Down+Down+Down:
.IP
See <X11/keysymdef.h> header file for a list of Keysyms,
or use the 
.IR xev (1)
program.  Note: mapping of button
clicks to Keysyms may not work if \fB-modtweak\fR or \fB-xkb\fR is
needed for the Keysym.
.IP
If you include a modifier like "Shift_L" the
modifier's up/down state is toggled, e.g. to send
"The" use :Shift_L+t+Shift_L+h+e: (the 1st one is
shift down and the 2nd one is shift up). (note: the
initial state of the modifier is ignored and not reset)
To include button events use "Button1", ... etc.
.PP
\fB-nodragging\fR
.IP
Do not update the display during mouse dragging events
(mouse button held down).  Greatly improves response on
slow setups, but you lose all visual feedback for drags,
text selection, and some menu traversals.  It overrides
any \fB-pointer_mode\fR setting.
.PP
\fB-wireframe\fR \fI[str],\fR \fB-nowireframe\fR
.IP
Try to detect window moves or resizes when a mouse
button is held down and show a wireframe instead of
the full opaque window.  This is based completely on
heuristics and may not always work: it depends on your
window manager and even how you move things around.
See \fB-pointer_mode\fR below for discussion of the "bogging
down" problem this tries to avoid.
Default: \fB-wireframe\fR
.IP
Shorter aliases:  \fB-wf\fR [str]  and \fB-nowf\fR
.IP
The value "str" is optional and, of course, is
packed with many tunable parameters for this scheme:
.IP
Format: shade,linewidth,percent,T+B+L+R,mod,t1+t2+t3+t4
Default: 0xff,3,0,32+8+8+8,all,0.15+0.30+5.0+0.125
.IP
If you leave nothing between commas: ",," the default
value is used.  If you don't specify enough commas,
the trailing parameters are set to their defaults.
.IP
"shade" indicate the "color" for the wireframe,
usually a greyscale: 0-255, however for 16 and 32bpp you
can specify an rgb.txt X color (e.g. "dodgerblue") or
a value > 255 is treated as RGB (e.g. red is 0xff0000).
"linewidth" sets the width of the wireframe in pixels.
"percent" indicates to not apply the wireframe scheme
to windows with area less than this percent of the
full screen.
.IP
"T+B+L+R" indicates four integers for how close in
pixels the pointer has to be from the Top, Bottom, Left,
or Right edges of the window to consider wireframing.
This is a speedup to quickly exclude a window from being
wireframed: set them all to zero to not try the speedup
(scrolling and selecting text will likely be slower).
.IP
"mod" specifies if a button down event in the
interior of the window with a modifier key (Alt, Shift,
etc.) down should indicate a wireframe opportunity.
It can be "0" or "none" to skip it, "1" or "all"
to apply it to any modifier, or "Shift", "Alt",
"Control", "Meta", "Super", or "Hyper" to only
apply for that type of modifier key.
.IP
"t1+t2+t3+t4" specify four floating point times in
seconds: t1 is how long to wait for the pointer to move,
t2 is how long to wait for the window to start moving
or being resized (for some window managers this can be
rather long), t3 is how long to keep a wireframe moving
before repainting the window. t4 is the minimum time
between sending wireframe "animations".  If a slow
link is detected, these values may be automatically
changed to something better for a slow link.
.PP
\fB-wirecopyrect\fR \fImode,\fR \fB-nowirecopyrect\fR
.IP
Since the \fB-wireframe\fR mechanism evidently tracks moving
windows accurately, a speedup can be obtained by
telling the VNC viewers to locally copy the translated
window region.  This is the VNC CopyRect encoding:
the framebuffer update doesn't need to send the actual
new image data.
.IP
Shorter aliases:  \fB-wcr\fR [mode]  and \fB-nowcr\fR
.IP
"mode" can be "never" (same as \fB-nowirecopyrect)\fR
to never try the copyrect, "top" means only do it if
the window was not covered by any other windows, and
"always" means to translate the orginally unobscured
region (this may look odd as the remaining pieces come
in, but helps on a slow link).  Default: "always"
.IP
Note: there can be painting errors or slow response
when using \fB-scale\fR so you may want to disable CopyRect
in this case "\fB-wirecopyrect\fR \fInever\fR" on the command
line or by remote-control.  Or you can also use the
"\fB-scale\fR \fIxxx:nocr\fR" scale option.
.PP
\fB-debug_wireframe\fR
.IP
Turn on debugging info printout for the wireframe
heuristics.  "\fB-dwf\fR" is an alias.  Specify multiple
times for more output.
.PP
\fB-scrollcopyrect\fR \fImode,\fR \fB-noscrollcopyrect\fR
.IP
Like \fB-wirecopyrect,\fR but use heuristics to try to guess
if a window has scrolled its contents (either vertically
or horizontally).  This requires the RECORD X extension
to "snoop" on X applications (currently for certain
XCopyArea and XConfigureWindow X protocol requests).
Examples: Hitting <Return> in a terminal window when the
cursor was at the bottom, the text scrolls up one line.
Hitting <Down> arrow in a web browser window, the web
page scrolls up a small amount.  Or scrolling with a
scrollbar or mouse wheel.
.IP
Shorter aliases:  \fB-scr\fR [mode]  and \fB-noscr\fR
.IP
This scheme will not always detect scrolls, but when
it does there is a nice speedup from using the VNC
CopyRect encoding (see \fB-wirecopyrect).\fR  The speedup
is both in reduced network traffic and reduced X
framebuffer polling/copying.  On the other hand, it may
induce undesired transients (e.g. a terminal cursor
being scrolled up when it should not be) or other
painting errors (window tearing, bunching-up, etc).
These are automatically repaired in a short period
of time.  If this is unacceptable disable the feature
with \fB-noscrollcopyrect.\fR
.IP
Screen clearing kludges:  for testing at least, there
are some "magic key sequences" (must be done in less
than 1 second) to aid repairing painting errors that
may be seen when using this mode:
.IP
3 Alt_L's   in a row: resend whole screen,
4 Alt_L's   in a row: reread and resend whole screen,
3 Super_L's in a row: mark whole screen for polling,
4 Super_L's in a row: reset RECORD context,
5 Super_L's in a row: try to push a black screen
.IP
note: Alt_L is the Left "Alt" key (a single key)
Super_L is the Left "Super" key (Windows flag).
Both of these are modifier keys, and so should not
generate characters when pressed by themselves.  Also,
your VNC viewer may have its own refresh hot-key
or button.
.IP
"mode" can be "never" (same as \fB-noscrollcopyrect)\fR
to never try the copyrect, "keys" means to try it
in response to keystrokes only, "mouse" means to
try it in response to mouse events only, "always"
means to do both. Default: "always"
.IP
Note: there can be painting errors or slow response
when using \fB-scale\fR so you may want to disable CopyRect
in this case "\fB-scrollcopyrect\fR \fInever\fR" on the command
line or by remote-control.  Or you can also use the
"\fB-scale\fR \fIxxx:nocr\fR" scale option.
.PP
\fB-scr_area\fR \fIn\fR
.IP
Set the minimum area in pixels for a rectangle
to be considered for the \fB-scrollcopyrect\fR detection
scheme.  This is to avoid wasting the effort on small
rectangles that would be quickly updated the normal way.
E.g. suppose an app updated the position of its skinny
scrollbar first and then shifted the large panel
it controlled.  We want to be sure to skip the small
scrollbar and get the large panel. Default: 60000
.PP
\fB-scr_skip\fR \fIlist\fR
.IP
Skip scroll detection for applications matching
the comma separated list of strings in \fIlist\fR.
Some applications implement their scrolling in
strange ways where the XCopyArea, etc, also applies
to invisible portions of the window: if we CopyRect
those areas it looks awful during the scroll and
there may be painting errors left after the scroll.
Soffice.bin is the worst known offender.
.IP
Use "##" to denote the start of the application class
(e.g. "##XTerm") and "++" to denote the start
of the application instance name (e.g. "++xterm").
The string your list is matched against is of the form
"^^WM_NAME##Class++Instance<same-for-any-subwindows>"
The "xlsclients \fB-la"\fR command will provide this info.
.IP
If a pattern is prefixed with "KEY:" it only applies
to Keystroke generated scrolls (e.g. Up arrow).  If it
is prefixed with "MOUSE:" it only applies to Mouse
induced scrolls (e.g. dragging on a scrollbar).
Default: ##Soffice.bin,##StarOffice
.PP
\fB-scr_inc\fR \fIlist\fR
.IP
Opposite of \fB-scr_skip:\fR this list is consulted first
and if there is a match the window will be monitored
via RECORD for scrolls irrespective of \fB-scr_skip.\fR
Use \fB-scr_skip\fR '*' to skip anything that does not match
your \fB-scr_inc.\fR  Use \fB-scr_inc\fR '*' to include everything.
.PP
\fB-scr_keys\fR \fIlist\fR
.IP
For keystroke scroll detection, only apply the RECORD
heuristics to the comma separated list of keysyms in
\fIlist\fR.  You may find the RECORD overhead for every
one of your keystrokes disrupts typing too much, but you
don't want to turn it off completely with "\fB-scr\fR \fImouse\fR"
and \fB-scr_parms\fR does not work or is too confusing.
.IP
The listed keysyms can be numeric or the keysym
names in the <X11/keysymdef.h> header file or from the
.IR xev (1)
program.  Example: "\fB-scr_keys\fR \fIUp,Down,Return\fR".
One probably wants to have application specific lists
(e.g. for terminals, etc) but that is too icky to think
about for now...
.IP
If \fIlist\fR begins with the "-" character the list
is taken as an exclude list: all keysyms except those
list will be considered.  The special string "builtin"
expands to an internal list of keysyms that are likely
to cause scrolls.  BTW, by default modifier keys,
Shift_L, Control_R, etc, are skipped since they almost
never induce scrolling by themselves.
.PP
\fB-scr_term\fR \fIlist\fR
.IP
Yet another cosmetic kludge.  Apply shell/terminal
heuristics to applications matching comma separated
list (same as for \fB-scr_skip/-scr_inc).\fR  For example an
annoying transient under scroll detection is if you
hit Enter in a terminal shell with full text window,
the solid text cursor block will be scrolled up.
So for a short time there are two (or more) block
cursors on the screen.  There are similar scenarios,
(e.g. an output line is duplicated).
.IP
These transients are induced by the approximation of
scroll detection (e.g. it detects the scroll, but not
the fact that the block cursor was cleared just before
the scroll).  In nearly all cases these transient errors
are repaired when the true X framebuffer is consulted
by the normal polling.  But they are distracting, so
what this option provides is extra "padding" near the
bottom of the terminal window: a few extra lines near
the bottom will not be scrolled, but rather updated
from the actual X framebuffer.  This usually reduces
the annoying artifacts.  Use "none" to disable.
Default: "term"
.PP
\fB-scr_keyrepeat\fR \fIlo-hi\fR
.IP
If a key is held down (or otherwise repeats rapidly) and
this induces a rapid sequence of scrolls (e.g. holding
down an Arrow key) the "scrollcopyrect" detection
and overhead may not be able to keep up.  A time per
single scroll estimate is performed and if that estimate
predicts a sustainable scrollrate of keys per second
between "lo" and "hi" then repeated keys will be
DISCARDED to maintain the scrollrate. For example your
key autorepeat may be 25 keys/sec, but for a large
window or slow link only 8 scrolls per second can be
sustained, then roughly 2 out of every 3 repeated keys
will be discarded during this period. Default: "4-20"
.PP
\fB-scr_parms\fR \fIstring\fR
.IP
Set various parameters for the scrollcopyrect mode.
The format is similar to that for \fB-wireframe\fR and packed
with lots of parameters:
.IP
Format: T+B+L+R,t1+t2+t3,s1+s2+s3+s4+s5
Default: 0+64+32+32,0.02+0.10+0.9,0.03+0.06+0.5+0.1+5.0
.IP
If you leave nothing between commas: ",," the default
value is used.  If you don't specify enough commas,
the trailing parameters are set to their defaults.
.IP
"T+B+L+R" indicates four integers for how close in
pixels the pointer has to be from the Top, Bottom, Left,
or Right edges of the window to consider scrollcopyrect.
If \fB-wireframe\fR overlaps it takes precedence.  This is a
speedup to quickly exclude a window from being watched
for scrollcopyrect: set them all to zero to not try
the speedup (things like selecting text will likely
be slower).
.IP
"t1+t2+t3" specify three floating point times in
seconds that apply to scrollcopyrect detection with
*Keystroke* input: t1 is how long to wait after a key
is pressed for the first scroll, t2 is how long to keep
looking after a Keystroke scroll for more scrolls.
t3 is how frequently to try to update surrounding
scrollbars outside of the scrolling area (0.0 to
disable)
.IP
"s1+s2+s3+s4+s5" specify five floating point times
in seconds that apply to scrollcopyrect detection with
*Mouse* input: s1 is how long to wait after a mouse
button is pressed for the first scroll, s2 is how long
to keep waiting for additional scrolls after the first
Mouse scroll was detected.  s3 is how frequently to
try to update surrounding scrollbars outside of the
scrolling area (0.0 to disable).  s4 is how long to
buffer pointer motion (to try to get fewer, bigger
mouse scrolls). s5 is the maximum time to spend just
updating the scroll window without updating the rest
of the screen.
.PP
\fB-fixscreen\fR \fIstring\fR
.IP
Periodically "repair" the screen based on settings
in \fIstring\fR.  Hopefully you won't need this option,
it is intended for cases when the \fB-scrollcopyrect\fR or
\fB-wirecopyrect\fR features leave too many painting errors,
but it can be used for any scenario.  This option
periodically performs costly operations and so
interactive response may be reduced when it is on.
You can use 3 Alt_L's (the Left "Alt" key) taps in a
row described under \fB-scrollcopyrect\fR instead to manually
request a screen repaint when it is needed.
.IP
\fIstring\fR is a comma separated list of one or more of
the following: "V=t", "C=t", and "X=t".  In these
"t" stands for a time in seconds (it is a floating
point even though one should usually use values > 2 to
avoid wasting resources).  V sets how frequently the
entire screen should be sent to viewers (it is like the
3 Alt_L's).  C sets how long to wait after a CopyRect
to repaint the full screen.  X sets how frequently
to reread the full X11 framebuffer from the X server
and push it out to connected viewers.  Use of X should
be rare, please report a bug if you find you need it.
Examples: \fB-fixscreen\fR V=10 \fB-fixscreen\fR C=10
.PP
\fB-debug_scroll\fR
.IP
Turn on debugging info printout for the scroll
heuristics.  "\fB-ds\fR" is an alias.  Specify it multiple
times for more output.
.PP
\fB-noxrecord\fR
.IP
Disable any use of the RECORD extension.  This is
currently used by the \fB-scrollcopyrect\fR scheme and to
monitor X server grabs.
.PP
\fB-grab_buster,\fR \fB-nograb_buster\fR
.IP
Some of the use of the RECORD extension can leave a
tiny window for XGrabServer deadlock.  This is only if
the whole-server grabbing application expects mouse or
keyboard input before releasing the grab.  It is usually
a window manager that does this.  x11vnc takes care to
avoid the the problem, but if caught x11vnc will freeze.
Without \fB-grab_buster,\fR the only solution is to go the
physical display and give it some input to satisfy the
grabbing app.  Or manually kill and restart the window
manager if that is feasible.  With \fB-grab_buster,\fR x11vnc
will fork a helper thread and if x11vnc appears to be
stuck in a grab after a period of time (20-30 sec) then
it will inject some user input: button clicks, Escape,
mouse motion, etc to try to break the grab.  If you
experience a lot of grab deadlock, please report a bug.
.PP
\fB-debug_grabs\fR
.IP
Turn on debugging info printout with respect to
XGrabServer() deadlock for \fB-scrollcopyrect__mode_.\fR
.PP
\fB-pointer_mode\fR \fIn\fR
.IP
Various pointer motion update schemes. "\fB-pm\fR" is
an alias.  The problem is pointer motion can cause
rapid changes on the screen: consider the rapid
changes when you drag a large window around opaquely.
Neither x11vnc's screen polling and vnc compression
routines nor the bandwidth to the vncviewers can keep
up these rapid screen changes: everything will bog down
when dragging or scrolling.  So a scheme has to be used
to "eat" much of that pointer input before re-polling
the screen and sending out framebuffer updates. The
mode number \fIn\fR can be 0 to 4 and selects one of
the schemes desribed below.
.IP
Note that the \fB-wireframe\fR and \fB-scrollcopyrect__mode_s\fR
complement \fB-pointer_mode\fR by detecting (and improving)
certain periods of "rapid screen change".
.IP
n=0: does the same as \fB-nodragging.\fR (all screen polling
is suspended if a mouse button is pressed.)
.IP
n=1: was the original scheme used to about Jan 2004:
it basically just skips \fB-input_skip\fR keyboard or pointer
events before repolling the screen.
.IP
n=2 is an improved scheme: by watching the current rate
of input events it tries to detect if it should try to
"eat" additional pointer events before continuing.
.IP
n=3 is basically a dynamic \fB-nodragging\fR mode: it detects
when the mouse motion has paused and then refreshes
the display.
.IP
n=4 attempts to measures network rates and latency,
the video card read rate, and how many tiles have been
changed on the screen.  From this, it aggressively tries
to push screen "frames" when it decides it has enough
resources to do so.  NOT FINISHED.
.IP
The default n is 2. Note that modes 2, 3, 4 will skip
\fB-input_skip\fR keyboard events (but it will not count
pointer events).  Also note that these modes are not
available in \fB-threads\fR mode which has its own pointer
event handling mechanism.
.IP
To try out the different pointer modes to see which
one gives the best response for your usage, it is
convenient to use the remote control function, for
example "x11vnc \fB-R\fR pm:4" or the tcl/tk gui (Tuning ->
pointer_mode -> n).
.PP
\fB-input_skip\fR \fIn\fR
.IP
For the pointer handling when non-threaded: try to
read n user input events before scanning display. n < 0
means to act as though there is always user input.
Default: 10
.PP
\fB-speeds\fR \fIrd,bw,lat\fR
.IP
x11vnc tries to estimate some speed parameters that
are used to optimize scheduling (e.g. \fB-pointer_mode\fR
4, \fB-wireframe,\fR \fB-scrollcopyrect)\fR and other things.
Use the \fB-speeds\fR option to set these manually.
The triple \fIrd,bw,lat\fR corresponds to video h/w
read rate in MB/sec, network bandwidth to clients in
KB/sec, and network latency to clients in milliseconds,
respectively.  If a value is left blank, e.g. "-speeds
,100,15", then the internal scheme is used to estimate
the empty value(s).
.IP
Typical PC video cards have read rates of 5-10 MB/sec.
If the framebuffer is in main memory instead of video
h/w (e.g. SunRay, shadowfb, dummy driver, Xvfb), the
read rate may be much faster.  "x11perf \fB-getimage500"\fR
can be used to get a lower bound (remember to factor
in the bytes per pixel).  It is up to you to estimate
the network bandwith and latency to clients.  For the
latency the 
.IR ping (1)
command can be used.
.IP
For convenience there are some aliases provided,
e.g. "\fB-speeds\fR \fImodem\fR".  The aliases are: "modem" for
6,4,200; "dsl" for 6,100,50; and "lan" for 6,5000,1
.PP
\fB-wmdt\fR \fIstring\fR
.IP
For some features, e.g. \fB-wireframe\fR and \fB-scrollcopyrect,\fR
x11vnc has to work around issues for certain window
managers or desktops (currently kde and xfce).
By default it tries to guess which one, but it can
guess incorrectly.  Use this option to indicate which
wm/dt.  \fIstring\fR can be "gnome", "kde", "cde",
"xfce", or "root" (classic X wm).  Anything else
is interpreted as "root".
.PP
\fB-debug_pointer\fR
.IP
Print debugging output for every pointer event.
.PP
\fB-debug_keyboard\fR
.IP
Print debugging output for every keyboard event.
.PP
Same as \fB-dp\fR and \fB-dk,\fR respectively.  Use multiple
times for more output.
.PP
\fB-defer\fR \fItime\fR
.IP
Time in ms to wait for updates before sending to client
(deferUpdateTime)  Default: 30
.PP
\fB-wait\fR \fItime\fR
.IP
Time in ms to pause between screen polls.  Used to cut
down on load.  Default: 30
.PP
\fB-wait_ui\fR \fIfactor\fR
.IP
Factor by which to cut the \fB-wait\fR time if there
has been recent user input (pointer or keyboard).
Improves response, but increases the load whenever you
are moving the mouse or typing.  Default: 2.00
.PP
\fB-nowait_bog\fR
.IP
Do not detect if the screen polling is "bogging down"
and sleep more.  Some activities with no user input can
slow things down a lot: consider a large terminal window
with a long build running in it continously streaming
text output.  By default x11vnc will try to detect this
(3 screen polls in a row each longer than 0.25 sec with
no user input), and sleep up to 1.5 secs to let things
"catch up".  Use this option to disable that detection.
.PP
\fB-slow_fb\fR \fItime\fR
.IP
Floating point time in seconds delay all screen polling.
For special purpose usage where a low frame rate is
acceptable and desirable, but you want the user input
processed at the normal rate so you cannot use \fB-wait.\fR
.PP
\fB-readtimeout\fR \fIn\fR
.IP
Set libvncserver rfbMaxClientWait to n seconds. On
slow links that take a long time to paint the first
screen libvncserver may hit the timeout and drop the
connection.  Default: 20 seconds.
.PP
\fB-nap\fR
.IP
Monitor activity and if it is low take longer naps
.PP
\fB-nonap\fR
.IP
between screen polls to really cut down load when idle.
Default: take naps
.PP
\fB-sb\fR \fItime\fR
.IP
Time in seconds after NO activity (e.g. screen blank)
to really throttle down the screen polls (i.e. sleep
for about 1.5 secs). Use 0 to disable.  Default: 60
.PP
\fB-noxdamage\fR
.IP
Do not use the X DAMAGE extension to detect framebuffer
changes even if it is available.  Use \fB-xdamage\fR if your
default is to have it off.
.IP
x11vnc's use of the DAMAGE extension: 1) significantly
reduces the load when the screen is not changing much,
and 2) detects changed areas (small ones by default)
more quickly.
.IP
Currently the DAMAGE extension is overly conservative
and often reports large areas (e.g. a whole terminal
or browser window) as damaged even though the actual
changed region is much smaller (sometimes just a few
pixels).  So heuristics were introduced to skip large
areas and use the damage rectangles only as "hints"
for the traditional scanline polling.  The following
tuning parameters are introduced to adjust this
behavior:
.PP
\fB-xd_area\fR \fIA\fR
.IP
Set the largest DAMAGE rectangle area \fIA\fR (in
pixels: width * height) to trust as truly damaged:
the rectangle will be copied from the framebuffer
(slow) no matter what.  Set to zero to trust *all*
rectangles. Default: 20000
.PP
\fB-xd_mem\fR \fIf\fR
.IP
Set how long DAMAGE rectangles should be "remembered",
\fIf\fR is a floating point number and is in units of the
scanline repeat cycle time (32 iterations).  The default
(1.0) should give no painting problems. Increase it if
there are problems or decrease it to live on the edge
(perhaps useful on a slow machine).
.PP
\fB-sigpipe\fR \fIstring\fR
.IP
Broken pipe (SIGPIPE) handling.  \fIstring\fR can be
"ignore" or "exit".  For "ignore" libvncserver
will handle the abrupt loss of a client and continue,
for "exit" x11vnc will cleanup and exit at the 1st
broken connection.  Default: "ignore".  This option
is obsolete.
.PP
\fB-threads,\fR \fB-nothreads\fR
.IP
Whether or not to use the threaded libvncserver
algorithm [rfbRunEventLoop] if libpthread is available
Default: \fB-nothreads\fR
.PP
\fB-fs\fR \fIf\fR
.IP
If the fraction of changed tiles in a poll is greater
than f, the whole screen is updated.  Default: 0.75
.PP
\fB-gaps\fR \fIn\fR
.IP
Heuristic to fill in gaps in rows or cols of n or
less tiles.  Used to improve text paging.  Default: 4
.PP
\fB-grow\fR \fIn\fR
.IP
Heuristic to grow islands of changed tiles n or wider
by checking the tile near the boundary.  Default: 3
.PP
\fB-fuzz\fR \fIn\fR
.IP
Tolerance in pixels to mark a tiles edges as changed.
Default: 2
.PP
\fB-debug_tiles\fR
.IP
Print debugging output for tiles, fb updates, etc.
.PP
\fB-snapfb\fR
.IP
Instead of polling the X display framebuffer (fb) for
changes, periodically copy all of X display fb into main
memory and examine that copy for changes.  Under some
circumstances this will improve interactive response,
or at least make things look smoother, but in others
(most!) it will make the response worse.  If the video
h/w fb is such that reading small tiles is very slow
this mode could help.  To keep the "framerate" up
the screen size x bpp cannot be too large.  Note that
this mode is very wasteful of memory I/O resources
(it makes full screen copies even if nothing changes).
It may be of use in video capture-like applications,
or where window tearing is a problem.
.PP
\fB-rawfb\fR \fIstring\fR
.IP
Experimental option, instead of polling X, poll the
memory object specified in \fIstring\fR.  For shared
memory segments it is of the form: "shm:N@WxHxB"
which specifies a shmid N and framebuffer Width, Height,
and Bits per pixel.  To memory map 
.IR mmap (2)
a file use:
"map:/path/to/a/file@WxHxB".  If there is trouble
with mmap, use  "file:/..." for slower 
.IR lseek (2)
based reading.  If you do not supply a type "map"
is assumed if the file exists.
.IP
If string is "setup:cmd", then the command "cmd"
is run and the first line from it is read and used
as \fIstring\fR.  This allows initializing the device,
determining WxHxB, etc. These are often done as root
so take care.
.IP
Optional suffixes are ":R/G/B" and "+O" to specify
red, green, and blue masks and an offset into the
memory object.  If the masks are not provided x11vnc
guesses them based on the bpp.
.IP
Examples:
.IP
\fB-rawfb\fR shm:210337933@800x600x32:ff/ff00/ff0000
.IP
\fB-rawfb\fR map:/dev/fb0@1024x768x32
.IP
\fB-rawfb\fR map:/tmp/Xvfb_screen0@640x480x8+3232
.IP
\fB-rawfb\fR file:/tmp/my.pnm@250x200x24+37
.IP
(see 
.IR ipcs (1)
and 
.IR fbset (1)
for the first two examples)
.IP
All user input is discarded by default (but see the
\fB-pipeinput\fR option).  Most of the X11 (screen, keyboard,
mouse) options do not make sense and many will cause
this mode to crash, so please think twice before
setting/changing them.
.IP
If you don't want x11vnc to close the X DISPLAY in
rawfb mode, then capitalize the prefix, SHM:, MAP:,
FILE:   Keeping the display open enables the default
remote-control channel, which could be useful.  Also,
if you also specify \fB-noviewonly,\fR then the mouse and
keyboard input are STILL sent to the X display, this
usage should be very rare, i.e. doing something strange
with /dev/fb0.
.PP
\fB-pipeinput\fR \fIcmd\fR
.IP
Another experimental option: it lets you supply an
external command in \fIcmd\fR that x11vnc will pipe
all of the user input events to in a simple format.
In \fB-pipeinput\fR mode by default x11vnc will not process
any of the user input events.  If you prefix \fIcmd\fR
with "tee:" it will both send them to the pipe
command and process them.  For a description of the
format run "\fB-pipeinput\fR \fItee:/bin/cat\fR".  Another prefix
is "reopen" which means to reopen pipe if it exits.
Separate multiple prefixes with commas.
.IP
In combination with \fB-rawfb\fR one might be able to
do amusing things (e.g. control non-X devices).
To facilitate this, if \fB-rawfb\fR is in effect then the
value is stored in X11VNC_RAWFB_STR for the pipe command
to use if it wants. Do 'env | grep X11VNC' for more.
.PP
\fB-gui\fR \fI[gui-opts]\fR
.IP
Start up a simple tcl/tk gui based on the the remote
control options \fB-remote/-query\fR described below.
Requires the "wish" program to be installed on the
machine.  "gui-opts" is not required: the default
is to start up both the full gui and x11vnc with the
gui showing up on the X display in the environment
variable DISPLAY.
.IP
"gui-opts" can be a comma separated list of items.
Currently there are these types of items: 1) a gui
mode, a 2) gui "simplicity", 3) the X display the
gui should display on, 4) a "tray" or "icon" mode,
and 5) a gui geometry.
.IP
1) The gui mode can be "start", "conn", or "wait"
"start" is the default mode above and is not required.
"conn" means do not automatically start up x11vnc,
but instead just try to connect to an existing x11vnc
process.  "wait" means just start the gui and nothing
else (you will later instruct the gui to start x11vnc
or connect to an existing one.)
.IP
2) The gui simplicity is off by default (a power-user
gui with all options is presented) To start with
something less daunting supply the string "simple"
("ez" is an alias for this).  Once the gui is
started you can toggle between the two with "Misc ->
simple_gui".
.IP
3) Note the possible confusion regarding the potentially
two different X displays: x11vnc polls one, but you
may want the gui to appear on another.  For example, if
you ssh in and x11vnc is not running yet you may want
the gui to come back to you via your ssh redirected X
display (e.g. localhost:10).
.IP
If you do not specify a gui X display in "gui-opts"
then the DISPLAY environment variable and \fB-display\fR
option are tried (in that order).  Regarding the x11vnc
X display the gui will try to communication with, it
first tries \fB-display\fR and then DISPLAY.  For example,
"x11vnc \fB-display\fR :0 \fB-gui\fR otherhost:0", will remote
control an x11vnc polling :0 and display the gui on
otherhost:0 The "tray/icon" mode below reverses this
preference, preferring to display on the x11vnc display.
.IP
4) When "tray" or "icon" is specified, the gui
presents itself as a small icon with behavior typical
of a "system tray" or "dock applet".  The color
of the icon indicates status (connected clients) and
there is also a balloon status.  Clicking on the icon
gives a menu from which properties, etc, can be set and
the full gui is available under "Advanced".  To be
fully functional, the gui mode should be "start"
(the default).
.IP
For "icon" the gui just a small standalone window.
For "tray" it will attempt to embed itself in the
"system tray" if possible. If "=setpass" is appended then
at startup the X11 user will be prompted to set the
VNC session password.  If =<hexnumber> is appended
that icon will attempt to embed itself in the window
given by hexnumber.  Use =noadvanced to disable the
full gui. (To supply more than one, use "+" sign).
E.g. \fB-gui\fR tray=setpass and \fB-gui\fR icon=0x3600028
.IP
Other modes: "full", the default and need not be
specified.  "\fB-gui\fR \fInone\fR", do not show a gui, useful
to override a ~/.x11vncrc setting, etc.
.IP
5) When "geom=+X+Y" is specified, that geometry
is passed to the gui toplevel.  This is the icon in
icon/tray mode, or the full gui otherwise.  You can
also specify width and height, i.e. WxH+X+Y, but it
is not recommended.  In "tray" mode the geometry is
ignored unless the system tray manager does not seem
to be running.  One could imagine using something like
"\fB-gui\fR \fItray,geom=+4000+4000\fR" with a display manager
to keep the gui invisible until someone logs in...
.IP
More icon tricks, "icon=minimal" gives an icon just
with the VNC display number.  You can also set the font
with "iconfont=...".  The following could be useful:
"\fB-gui\fR \fIicon=minimal,iconfont=5x8,geom=24x10+0-0\fR"
.IP
General examples of the \fB-gui\fR option: "x11vnc \fB-gui",\fR
"x11vnc \fB-gui\fR ez" "x11vnc \fB-gui\fR localhost:10",
"x11vnc \fB-gui\fR conn,host:0", "x11vnc \fB-gui\fR tray,ez"
"x11vnc \fB-gui\fR tray=setpass"
.IP
If you do not intend to start x11vnc from the gui
(i.e. just remote control an existing one), then the
gui process can run on a different machine from the
x11vnc server as long as X permissions, etc. permit
communication between the two.
.PP
\fB-remote\fR \fIcommand\fR
.IP
Remotely control some aspects of an already running
x11vnc server.  "\fB-R\fR" and "\fB-r\fR" are aliases for
"\fB-remote\fR".  After the remote control command is
sent to the running server the 'x11vnc \fB-remote\fR ...'
command exits.  You can often use the \fB-query\fR command
(see below) to see if the x11vnc server processed your
\fB-remote\fR command.
.IP
The default communication channel is that of X
properties (specifically VNC_CONNECT), and so this
command must be run with correct settings for DISPLAY
and possibly XAUTHORITY to connect to the X server
and set the property.  Alternatively, use the \fB-display\fR
and \fB-auth\fR options to set them to the correct values.
The running server cannot use the \fB-novncconnect\fR option
because that disables the communication channel.
See below for alternate channels.
.IP
For example: 'x11vnc \fB-remote\fR stop' (which is the same as
\'x11vnc \fB-R\fR stop') will close down the x11vnc server.
\'x11vnc \fB-R\fR shared' will enable shared connections, and
\'x11vnc \fB-R\fR scale:3/4' will rescale the desktop.
.IP
.IP
The following \fB-remote/-R\fR commands are supported:
.IP
stop            terminate the server, same as "quit"
"exit" or "shutdown".
.IP
ping            see if the x11vnc server responds.
Return is: ans=ping:<xdisplay>
.IP
blacken         try to push a black fb update to all
clients (due to timings a client
could miss it). Same as "zero", also
"zero:x1,y1,x2,y2" for a rectangle.
.IP
refresh         send the entire fb to all clients.
.IP
reset           recreate the fb, polling memory, etc.
.IP
id:windowid     set \fB-id\fR window to "windowid". empty
or "root" to go back to root window
.IP
sid:windowid    set \fB-sid\fR window to "windowid"
.IP
waitmapped      wait until subwin is mapped.
.IP
nowaitmapped    do not wait until subwin is mapped.
.IP
clip:WxH+X+Y    set \fB-clip\fR mode to "WxH+X+Y"
.IP
flashcmap       enable  \fB-flashcmap\fR mode.
.IP
noflashcmap     disable \fB-flashcmap\fR mode.
.IP
shiftcmap:n     set \fB-shiftcmap\fR to n.
.IP
notruecolor     enable  \fB-notruecolor\fR mode.
.IP
truecolor       disable \fB-notruecolor\fR mode.
.IP
overlay         enable  \fB-overlay\fR mode (if applicable).
.IP
nooverlay       disable \fB-overlay\fR mode.
.IP
overlay_cursor  in \fB-overlay\fR mode, enable cursor drawing.
.IP
overlay_nocursor disable cursor drawing. same as
nooverlay_cursor.
.IP
visual:vis      set \fB-visual\fR to "vis"
.IP
scale:frac      set \fB-scale\fR to "frac"
.IP
scale_cursor:f  set \fB-scale_cursor\fR to "f"
.IP
viewonly        enable  \fB-viewonly\fR mode.
.IP
noviewonly      disable \fB-viewonly\fR mode.
.IP
shared          enable  \fB-shared\fR mode.
.IP
noshared        disable \fB-shared\fR mode.
.IP
forever         enable  \fB-forever\fR mode.
.IP
noforever       disable \fB-forever\fR mode.
.IP
timeout:n       reset \fB-timeout\fR to n, if there are
currently no clients, exit unless one
connects in the next n secs.
.IP
http            enable  http client connections.
.IP
nohttp          disable http client connections.
.IP
deny            deny any new connections, same as "lock"
.IP
nodeny          allow new connections, same as "unlock"
.IP
connect:host    do reverse connection to host, "host"
may be a comma separated list of hosts
or host:ports.  See \fB-connect.\fR
.IP
disconnect:host disconnect any clients from "host"
same as "close:host".  Use host
"all" to close all current clients.
If you know the client internal hex ID,
e.g. 0x3 (returned by "\fB-query\fR \fIclients\fR"
and RFB_CLIENT_ID) you can use that too.
.IP
allowonce:host  For the next connection only, allow
connection from "host".
.IP
allow:hostlist  set \fB-allow\fR list to (comma separated)
"hostlist". See \fB-allow\fR and \fB-localhost.\fR
Do not use with \fB-allow\fR /path/to/file
Use "+host" to add a single host, and
use "\fB-host\fR" to delete a single host
.IP
localhost       enable  \fB-localhost\fR mode
.IP
nolocalhost     disable \fB-localhost\fR mode
.IP
listen:str      set \fB-listen\fR to str, empty to disable.
.IP
nolookup        enable  \fB-nolookup\fR mode.
.IP
lookup          disable \fB-nolookup\fR mode.
.IP
input:str       set \fB-input\fR to "str", empty to disable.
.IP
client_input:str set the K, M, B \fB-input\fR on a per-client
basis.  select which client as for
disconnect, e.g. client_input:host:MB
or client_input:0x2:K
.IP
accept:cmd      set \fB-accept\fR "cmd" (empty to disable).
.IP
afteraccept:cmd set \fB-afteraccept\fR (empty to disable).
.IP
gone:cmd        set \fB-gone\fR "cmd" (empty to disable).
.IP
noshm           enable  \fB-noshm\fR mode.
.IP
shm             disable \fB-noshm\fR mode (i.e. use shm).
.IP
flipbyteorder   enable \fB-flipbyteorder\fR mode, you may need
to set noshm for this to do something.
.IP
noflipbyteorder disable \fB-flipbyteorder\fR mode.
.IP
onetile         enable  \fB-onetile\fR mode. (you may need to
set shm for this to do something)
.IP
noonetile       disable \fB-onetile\fR mode.
.IP
solid           enable  \fB-solid\fR mode
.IP
nosolid         disable \fB-solid\fR mode.
.IP
solid_color:color set \fB-solid\fR color (and apply it).
.IP
blackout:str    set \fB-blackout\fR "str" (empty to disable).
See \fB-blackout\fR for the form of "str"
(basically: WxH+X+Y,...)
Use "+WxH+X+Y" to append a single
rectangle use "-WxH+X+Y" to delete one
.IP
xinerama        enable  \fB-xinerama\fR mode. (if applicable)
.IP
noxinerama      disable \fB-xinerama\fR mode.
.IP
xtrap           enable  \fB-xtrap\fR input mode(if applicable)
.IP
noxtrap         disable \fB-xtrap\fR input mode.
.IP
xrandr          enable  \fB-xrandr\fR mode. (if applicable)
.IP
noxrandr        disable \fB-xrandr\fR mode.
.IP
xrandr_mode:mode set the \fB-xrandr\fR mode to "mode".
.IP
padgeom:WxH     set \fB-padgeom\fR to WxH (empty to disable)
If WxH is "force" or "do" the padded
geometry fb is immediately applied.
.IP
quiet           enable  \fB-quiet\fR mode.
.IP
noquiet         disable \fB-quiet\fR mode.
.IP
modtweak        enable  \fB-modtweak\fR mode.
.IP
nomodtweak      enable  \fB-nomodtweak\fR mode.
.IP
xkb             enable  \fB-xkb\fR modtweak mode.
.IP
noxkb           disable \fB-xkb\fR modtweak mode.
.IP
skip_keycodes:str enable \fB-xkb\fR \fB-skip_keycodes\fR "str".
.IP
sloppy_keys     enable  \fB-sloppy_keys\fR mode.
.IP
nosloppy_keys   disable \fB-sloppy_keys\fR mode.
.IP
skip_dups       enable  \fB-skip_dups\fR mode.
.IP
noskip_dups     disable \fB-skip_dups\fR mode.
.IP
add_keysyms     enable \fB-add_keysyms\fR mode.
.IP
noadd_keysyms   stop adding keysyms. those added will
still be removed at exit.
.IP
clear_mods      enable  \fB-clear_mods\fR mode and clear them.
.IP
noclear_mods    disable \fB-clear_mods\fR mode.
.IP
clear_keys      enable  \fB-clear_keys\fR mode and clear them.
.IP
noclear_keys    disable \fB-clear_keys\fR mode.
.IP
remap:str       set \fB-remap\fR "str" (empty to disable).
See \fB-remap\fR for the form of "str"
(basically: key1-key2,key3-key4,...)
Use "+key1-key2" to append a single
keymapping, use "-key1-key2" to delete.
.IP
norepeat        enable  \fB-norepeat\fR mode.
.IP
repeat          disable \fB-norepeat\fR mode.
.IP
nofb            enable  \fB-nofb\fR mode.
.IP
fb              disable \fB-nofb\fR mode.
.IP
bell            enable  bell (if supported).
.IP
nobell          disable bell.
.IP
nosel           enable  \fB-nosel\fR mode.
.IP
sel             disable \fB-nosel\fR mode.
.IP
noprimary       enable  \fB-noprimary\fR mode.
.IP
primary         disable \fB-noprimary\fR mode.
.IP
seldir:str      set \fB-seldir\fR to "str"
.IP
cursor:mode     enable  \fB-cursor\fR "mode".
.IP
show_cursor     enable  showing a cursor.
.IP
noshow_cursor   disable showing a cursor. (same as
"nocursor")
.IP
arrow:n         set \fB-arrow\fR to alternate n.
.IP
xfixes          enable  xfixes cursor shape mode.
.IP
noxfixes        disable xfixes cursor shape mode.
.IP
alphacut:n      set \fB-alphacut\fR to n.
.IP
alphafrac:f     set \fB-alphafrac\fR to f.
.IP
alpharemove     enable  \fB-alpharemove\fR mode.
.IP
noalpharemove   disable \fB-alpharemove\fR mode.
.IP
alphablend      disable \fB-noalphablend\fR mode.
.IP
noalphablend    enable  \fB-noalphablend\fR mode.
.IP
cursorshape     disable \fB-nocursorshape\fR mode.
.IP
nocursorshape   enable  \fB-nocursorshape\fR mode.
.IP
cursorpos       disable \fB-nocursorpos\fR mode.
.IP
nocursorpos     enable  \fB-nocursorpos\fR mode.
.IP
xwarp           enable  \fB-xwarppointer\fR mode.
.IP
noxwarp         disable \fB-xwarppointer\fR mode.
.IP
buttonmap:str   set \fB-buttonmap\fR "str", empty to disable
.IP
dragging        disable \fB-nodragging\fR mode.
.IP
nodragging      enable  \fB-nodragging\fR mode.
.IP
wireframe       enable  \fB-wireframe\fR mode. same as "wf"
.IP
nowireframe     disable \fB-wireframe\fR mode. same as "nowf"
.IP
wireframe:str   enable  \fB-wireframe\fR mode string.
.IP
wireframe_mode:str enable  \fB-wireframe\fR mode string.
.IP
wirecopyrect:str set \fB-wirecopyrect\fR string. same as "wcr:"
.IP
scrollcopyrect:str set \fB-scrollcopyrect\fR string. same "scr"
.IP
noscrollcopyrect disable \fB-scrollcopyrect__mode_.\fR "noscr"
.IP
scr_area:n      set \fB-scr_area\fR to n
.IP
scr_skip:list   set \fB-scr_skip\fR to "list"
.IP
scr_inc:list    set \fB-scr_inc\fR to "list"
.IP
scr_keys:list   set \fB-scr_keys\fR to "list"
.IP
scr_term:list   set \fB-scr_term\fR to "list"
.IP
scr_keyrepeat:str set \fB-scr_keyrepeat\fR to "str"
.IP
scr_parms:str   set \fB-scr_parms\fR parameters.
.IP
fixscreen:str   set \fB-fixscreen\fR to "str".
.IP
noxrecord       disable all use of RECORD extension.
.IP
xrecord         enable  use of RECORD extension.
.IP
reset_record    reset RECORD extension (if avail.)
.IP
pointer_mode:n  set \fB-pointer_mode\fR to n. same as "pm"
.IP
input_skip:n    set \fB-input_skip\fR to n.
.IP
speeds:str      set \fB-speeds\fR to str.
.IP
wmdt:str        set \fB-wmdt\fR to str.
.IP
debug_pointer   enable  \fB-debug_pointer,\fR same as "dp"
.IP
nodebug_pointer disable \fB-debug_pointer,\fR same as "nodp"
.IP
debug_keyboard   enable  \fB-debug_keyboard,\fR same as "dk"
.IP
nodebug_keyboard disable \fB-debug_keyboard,\fR same as "nodk"
.IP
defer:n         set \fB-defer\fR to n ms,same as deferupdate:n
.IP
wait:n          set \fB-wait\fR to n ms.
.IP
wait_ui:f       set \fB-wait_ui\fR factor to f.
.IP
wait_bog        disable \fB-nowait_bog\fR mode.
.IP
nowait_bog      enable  \fB-nowait_bog\fR mode.
.IP
slow_fb:f       set \fB-slow_fb\fR to f seconds.
.IP
readtimeout:n   set read timeout to n seconds.
.IP
nap             enable  \fB-nap\fR mode.
.IP
nonap           disable \fB-nap\fR mode.
.IP
sb:n            set \fB-sb\fR to n s, same as screen_blank:n
.IP
xdamage         enable  xdamage polling hints.
.IP
noxdamage       disable xdamage polling hints.
.IP
xd_area:A       set \fB-xd_area\fR max pixel area to "A"
.IP
xd_mem:f        set \fB-xd_mem\fR remembrance to "f"
.IP
fs:frac         set \fB-fs\fR fraction to "frac", e.g. 0.5
.IP
gaps:n          set \fB-gaps\fR to n.
.IP
grow:n          set \fB-grow\fR to n.
.IP
fuzz:n          set \fB-fuzz\fR to n.
.IP
snapfb          enable  \fB-snapfb\fR mode.
.IP
nosnapfb        disable \fB-snapfb\fR mode.
.IP
rawfb:str       set \fB-rawfb\fR mode to "str".
.IP
progressive:n   set libvncserver \fB-progressive\fR slice
height parameter to n.
.IP
desktop:str     set \fB-desktop\fR name to str for new clients.
.IP
rfbport:n       set \fB-rfbport\fR to n.
.IP
httpport:n      set \fB-httpport\fR to n.
.IP
httpdir:dir     set \fB-httpdir\fR to dir (and enable http).
.IP
enablehttpproxy   enable  \fB-enablehttpproxy\fR mode.
.IP
noenablehttpproxy disable \fB-enablehttpproxy\fR mode.
.IP
alwaysshared     enable  \fB-alwaysshared\fR mode.
.IP
noalwaysshared   disable \fB-alwaysshared\fR mode.
(may interfere with other options)
.IP
nevershared      enable  \fB-nevershared\fR mode.
.IP
nonevershared    disable \fB-nevershared\fR mode.
(may interfere with other options)
.IP
dontdisconnect   enable  \fB-dontdisconnect\fR mode.
.IP
nodontdisconnect disable \fB-dontdisconnect\fR mode.
(may interfere with other options)
.IP
debug_xevents   enable  debugging X events.
.IP
nodebug_xevents disable debugging X events.
.IP
debug_xdamage   enable  debugging X DAMAGE mechanism.
.IP
nodebug_xdamage disable debugging X DAMAGE mechanism.
.IP
debug_wireframe enable   debugging wireframe mechanism.
.IP
nodebug_wireframe disable debugging wireframe mechanism.
.IP
debug_scroll    enable  debugging scrollcopy mechanism.
.IP
nodebug_scroll  disable debugging scrollcopy mechanism.
.IP
debug_tiles     enable  \fB-debug_tiles\fR
.IP
nodebug_tiles   disable \fB-debug_tiles\fR
.IP
debug_grabs     enable  \fB-debug_grabs\fR
.IP
nodebug_grabs   disable \fB-debug_grabs\fR
.IP
dbg             enable  \fB-dbg\fR crash shell
.IP
nodbg           disable \fB-dbg\fR crash shell
.IP
.IP
noremote        disable the \fB-remote\fR command processing,
it cannot be turned back on.
.IP
.IP
The 
.IR vncconnect (1)
command from standard VNC
.IP
distributions may also be used if string is prefixed
.IP
with "cmd=" E.g. 'vncconnect cmd=stop'.  Under some
.IP
circumstances 
.IR xprop (1)
can used if it supports \fB-set\fR
.IP
(see the FAQ).
.IP
.IP
If "\fB-connect\fR \fI/path/to/file\fR" has been supplied to the
.IP
running x11vnc server then that file can be used as a
.IP
communication channel (this is the only way to remote
.IP
control one of many x11vnc's polling the same X display)
.IP
Simply run: 'x11vnc \fB-connect\fR /path/to/file \fB-remote\fR ...'
.IP
or you can directly write to the file via something
.IP
like: "echo cmd=stop > /path/to/file", etc.
.PP
\fB-query\fR \fIvariable\fR
.IP
Like \fB-remote,\fR except just query the value of
\fIvariable\fR.  "\fB-Q\fR" is an alias for "\fB-query\fR".
Multiple queries can be done by separating variables
by commas, e.g. \fB-query\fR var1,var2. The results come
back in the form ans=var1:value1,ans=var2:value2,...
to the standard output.  If a variable is read-only,
it comes back with prefix "aro=" instead of "ans=".
.IP
Some \fB-remote\fR commands are pure actions that do not make
sense as variables, e.g. "stop" or "disconnect",
in these cases the value returned is "N/A".  To direct
a query straight to the VNC_CONNECT property or connect
file use "qry=..." instead of "cmd=..."
.IP
Here is the current list of "variables" that can
be supplied to the \fB-query\fR command. This includes the
"N/A" ones that return no useful info.  For variables
names that do not correspond to an x11vnc option or
remote command, we hope the name makes it obvious what
the returned value corresponds to (hint: the ext_*
variables correspond to the presence of X extensions):
.IP
ans= stop quit exit shutdown ping blacken zero
refresh reset close disconnect id sid waitmapped
nowaitmapped clip flashcmap noflashcmap shiftcmap
truecolor notruecolor overlay nooverlay overlay_cursor
overlay_yescursor nooverlay_nocursor nooverlay_cursor
nooverlay_yescursor overlay_nocursor visual scale
scale_cursor viewonly noviewonly shared noshared
forever noforever once timeout filexfer deny lock
nodeny unlock connect allowonce allow localhost
nolocalhost listen lookup nolookup accept afteraccept
gone shm noshm flipbyteorder noflipbyteorder onetile
noonetile solid_color solid nosolid blackout xinerama
noxinerama xtrap noxtrap xrandr noxrandr xrandr_mode
padgeom quiet q noquiet modtweak nomodtweak xkb
noxkb skip_keycodes sloppy_keys nosloppy_keys
skip_dups noskip_dups add_keysyms noadd_keysyms
clear_mods noclear_mods clear_keys noclear_keys
remap repeat norepeat fb nofb bell nobell sel nosel
primary noprimary seldir cursorshape nocursorshape
cursorpos nocursorpos cursor show_cursor noshow_cursor
nocursor arrow xfixes noxfixes xdamage noxdamage
xd_area xd_mem alphacut alphafrac alpharemove
noalpharemove alphablend noalphablend xwarppointer
xwarp noxwarppointer noxwarp buttonmap dragging
nodragging wireframe_mode wireframe wf nowireframe
nowf wirecopyrect wcr nowirecopyrect nowcr scr_area
scr_skip scr_inc scr_keys scr_term scr_keyrepeat
scr_parms scrollcopyrect scr noscrollcopyrect noscr
fixscreen noxrecord xrecord reset_record pointer_mode
pm input_skip input client_input speeds wmdt
debug_pointer dp nodebug_pointer nodp debug_keyboard
dk nodebug_keyboard nodk deferupdate defer wait_ui
wait_bog nowait_bog slow_fb wait readtimeout nap nonap
sb screen_blank fs gaps grow fuzz snapfb nosnapfb
rawfb progressive rfbport http nohttp httpport
httpdir enablehttpproxy noenablehttpproxy alwaysshared
noalwaysshared nevershared noalwaysshared dontdisconnect
nodontdisconnect desktop debug_xevents nodebug_xevents
debug_xevents debug_xdamage nodebug_xdamage
debug_xdamage debug_wireframe nodebug_wireframe
debug_wireframe debug_scroll nodebug_scroll debug_scroll
debug_tiles dbt nodebug_tiles nodbt debug_tiles
debug_grabs nodebug_grabs dbg nodbg noremote
.IP
aro=  noop display vncdisplay desktopname guess_desktop
http_url auth xauth users rootshift clipshift
scale_str scaled_x scaled_y scale_numer scale_denom
scale_fac scaling_blend scaling_nomult4 scaling_pad
scaling_interpolate inetd privremote unsafe safer nocmds
passwdfile using_shm logfile o flag rc norc h help V
version lastmod bg sigpipe threads readrate netrate
netlatency pipeinput clients client_count pid ext_xtest
ext_xtrap ext_xrecord ext_xkb ext_xshm ext_xinerama
ext_overlay ext_xfixes ext_xdamage ext_xrandr rootwin
num_buttons button_mask mouse_x mouse_y bpp depth
indexed_color dpy_x dpy_y wdpy_x wdpy_y off_x off_y
cdpy_x cdpy_y coff_x coff_y rfbauth passwd viewpasswd
.PP
\fB-QD\fR \fIvariable\fR
.IP
Just like \fB-query\fR variable, but returns the default
value for that parameter (no running x11vnc server
is consulted)
.PP
\fB-sync\fR
.IP
By default \fB-remote\fR commands are run asynchronously, that
is, the request is posted and the program immediately
exits.  Use \fB-sync\fR to have the program wait for an
acknowledgement from the x11vnc server that command was
processed (somehow).  On the other hand \fB-query\fR requests
are always processed synchronously because they have
to wait for the answer.
.IP
Also note that if both \fB-remote\fR and \fB-query\fR requests are
supplied on the command line, the \fB-remote\fR is processed
first (synchronously: no need for \fB-sync),\fR and then
the \fB-query\fR request is processed in the normal way.
This allows for a reliable way to see if the \fB-remote\fR
command was processed by querying for any new settings.
Note however that there is timeout of a few seconds so
if the x11vnc takes longer than that to process the
requests the requestor will think that a failure has
taken place.
.PP
\fB-noremote,\fR \fB-yesremote\fR
.IP
Do not process any remote control commands or queries.
Do process remote control commands or queries.
Default: \fB-yesremote\fR
.IP
A note about security wrt remote control commands.
If someone can connect to the X display and change
the property VNC_CONNECT, then they can remotely
control x11vnc.  Normally access to the X display is
protected.  Note that if they can modify VNC_CONNECT
on the X server, they have enough permissions to also
run their own x11vnc and thus have complete control
of the desktop.  If the  "\fB-connect\fR \fI/path/to/file\fR"
channel is being used, obviously anyone who can write
to /path/to/file can remotely control x11vnc.  So be
sure to protect the X display and that file's write
permissions.  See \fB-privremote\fR below.
.IP
If you are paranoid and do not think \fB-noremote\fR is
enough, to disable the VNC_CONNECT property channel
completely use \fB-novncconnect,\fR or use the \fB-safer\fR
option that shuts many things off.
.PP
\fB-unsafe\fR
.IP
A few remote commands are disabled by default
(currently: id:pick, accept:<cmd>, gone:<cmd>, and
rawfb:setup:<cmd>) because they are associated with
running external programs.  If you specify \fB-unsafe,\fR then
these remote-control commands are allowed.  Note that
you can still specify these parameters on the command
line, they just cannot be invoked via remote-control.
.PP
\fB-safer\fR
.IP
Equivalent to: \fB-novncconnect\fR \fB-noremote\fR and prohibiting
\fB-gui\fR and the \fB-connect\fR file. Shuts off communcation
channels.
.PP
\fB-privremote\fR
.IP
Perform some sanity checks and disable remote-control
commands if it appears that the X DISPLAY and/or
connectfile can be accessed by other users.  Once
remote-control is disabled it cannot be turned back on.
.PP
\fB-nocmds\fR
.IP
No external commands (e.g. 
.IR system (3)
, 
.IR popen (3)
, 
.IR exec (3)
)
will be run.
.PP
\fB-deny_all\fR
.IP
For use with \fB-remote\fR nodeny: start out denying all
incoming clients until "\fB-remote\fR \fInodeny\fR" is used to
let them in.
.PP
These options are passed to libvncserver:
.PP
\fB-rfbport\fR \fIport\fR
.IP
TCP port for RFB protocol
.PP
\fB-rfbwait\fR \fItime\fR
.IP
max time in ms to wait for RFB client
.PP
\fB-rfbauth\fR \fIpasswd-file\fR
.IP
use authentication on RFB protocol
(use 'storepasswd' to create a password file)
.PP
\fB-passwd\fR \fIplain-password\fR
.IP
use authentication
(use plain-password as password, USE AT YOUR RISK)
.PP
\fB-deferupdate\fR \fItime\fR
.IP
time in ms to defer updates (default 40)
.PP
\fB-deferptrupdate\fR \fItime\fR
.IP
time in ms to defer pointer updates (default none)
.PP
\fB-desktop\fR \fIname\fR
.IP
VNC desktop name (default "LibVNCServer")
.PP
\fB-alwaysshared\fR
.IP
always treat new clients as shared
.PP
\fB-nevershared\fR
.IP
never treat new clients as shared
.PP
\fB-dontdisconnect\fR
.IP
don't disconnect existing clients when a new non-shared
connection comes in (refuse new connection instead)
.PP
\fB-httpdir\fR \fIdir-path\fR
.IP
enable http server using dir-path home
.PP
\fB-httpport\fR \fIportnum\fR
.IP
use portnum for http connection
.PP
\fB-enablehttpproxy\fR
.IP
enable http proxy support
.PP
\fB-progressive\fR \fIheight\fR
.IP
enable progressive updating for slow links
.PP
\fB-listen\fR \fIipaddr\fR
.IP
listen for connections only on network interface with
addr ipaddr. '-listen localhost' and hostname work too.
.PP
libvncserver-tight-extension options:
.PP
\fB-disablefiletransfer\fR
.IP
disable file transfer
.PP
\fB-ftproot\fR \fIstring\fR
.IP
set ftp root
.SH "FILES"
.IR $HOME/.x11vncrc ,
.IR $HOME/.Xauthority
.SH "ENVIRONMENT"
.IR DISPLAY ,
.IR XAUTHORITY ,
.IR HOME
.PP
The following are set for the auxiliary commands
run by \fB-accept\fR and \fB-gone\fR:
.PP
.IR RFB_CLIENT_IP ,
.IR RFB_CLIENT_PORT ,
.IR RFB_SERVER_IP ,
.IR RFB_SERVER_PORT ,
.IR RFB_X11VNC_PID ,
.IR RFB_CLIENT_ID ,
.IR RFB_CLIENT_COUNT ,
.IR RFB_MODE
.SH "SEE ALSO"
.IR vncviewer (1),
.IR vncpasswd (1),
.IR vncconnect (1),
.IR vncserver (1),
.IR Xvnc (1),
.IR inetd (1),
.IR xev (1),
.IR xmodmap (1),
.IR Xserver (1),
.IR xauth (1),
.IR xhost (1),
.IR Xsecurity (7),
.IR xmessage (1),
.IR ipcrm (1),
.IR http://www.tightvnc.com ,
.IR http://www.realvnc.com ,
.IR http://www.karlrunge.com/x11vnc/ ,
.IR http://www.karlrunge.com/x11vnc/#faq
.SH AUTHORS
x11vnc was written by Karl J. Runge <runge@karlrunge.com>,
it is part of the LibVNCServer project <http://sf.net/projects/libvncserver>.
This manual page is based one the one written by Ludovic Drolez
<ldrolez@debian.org>, for the Debian project (both may be used by others).