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-rw-r--r--x11vnc/README579
1 files changed, 351 insertions, 228 deletions
diff --git a/x11vnc/README b/x11vnc/README
index efe43d5..7a0394a 100644
--- a/x11vnc/README
+++ b/x11vnc/README
@@ -1,5 +1,5 @@
-x11vnc README file Date: Thu Dec 16 23:32:54 EST 2004
+x11vnc README file Date: Sun Dec 19 23:34:22 EST 2004
The following information is taken from these URLs:
@@ -278,7 +278,8 @@ vncviewer -via $host localhost:0 # must be TightVNC vncviewer.
version of x11vnc (Oct 2003) that you likely want to avoid. Also, you
can get a copy of my latest, bleeding edge [22]x11vnc.c file to
replace the one in the above packages or the one in the CVS tree and
- then rebuild.
+ then rebuild. If you have an older libvncserver source tree, you may
+ need to switch on the OLD_TREE near the top of the x11vnc.c file.
See the [23]FAQ below for information about where you might obtain a
precompiled x11vnc binary from 3rd parties.
@@ -349,7 +350,7 @@ vncviewer -via $host localhost:0 # must be TightVNC vncviewer.
locations information to the libvncserver configuration:
#!/bin/sh
-# Build script for Solaris, etc, with, gcc, libjpeg and libz in
+# Build script for Solaris, etc, with gcc, libjpeg and libz in
# non-standard locations.
PATH=/path/to/gcc/bin:/usr/ccs/bin:$PATH # set to get gcc
@@ -368,6 +369,9 @@ LDFLAGS="-L $JPEG/lib -R $JPEG/lib -L $ZLIB/lib -R $ZLIB/lib"
CPPFLAGS="$CPPFLAGS -I /usr/openwin/include"
LDFLAGS="$LDFLAGS -L /usr/openwin/lib -R /usr/openwin/lib"
+# This only applies to Solaris 10 or later (XFIXES and DAMAGE)
+LDFLAGS="$LDFLAGS -L /usr/openwin/sfw/lib -R /usr/openwin/sfw/lib"
+
# Everything needs to built with _REENTRANT for thread safe errno:
CPPFLAGS="$CPPFLAGS -D_REENTRANT"
@@ -467,7 +471,8 @@ ls -l ./x11vnc/x11vnc
horizontal scanlines. This is a surprisingly effective algorithm for
finding changed regions. For keyboard and mouse user input the XTEST
extension is used to pass the input events to the X server. To detect
- XBell "beeps" the XKEYBOARD extension is used.
+ XBell "beeps" the XKEYBOARD extension is used. If available, the
+ XFIXES extension is used to retrieve the current mouse cursor shape.
Barbershop mirrors effect: What if x11vnc is started up, and
vncviewer is then started up on the same machine and displayed on the
@@ -539,12 +544,14 @@ ls -l ./x11vnc/x11vnc
dynamically...
* Somewhat surprisingly, the X11 mouse (cursor) shape is write-only
and cannot be queried from the X server. So in x11vnc the cursor
- shape stays fixed at an arrow. (see the "-cursor X" and other
- options, however, for a partial hack for the root window, etc.).
+ shape stays fixed at an arrow. (see the "-cursor X" and "-cursor
+ some", however, for a partial hack for the root window, etc.).
Also, on Solaris using the SUN_OVL overlay extension, x11vnc can
show the correct mouse cursor when the -overlay option is also
- supplied. For XFree86/Xorg, the XFIXES extension should help this
- as well.
+ supplied. A similar thing is done on IRIX as well when -overlay is
+ supplied. As of Dec/2004 x11vnc supports the XFIXES extension (in
+ Xorg and Solaris 10) to query the X server for the exact cursor
+ shape, this works pretty well.
* Audio from applications is of course not redirected (separate
redirectors do exist, e.g. esd). The XBell() "beeps" will work if
the X server supports the XKEYBOARD extension. (Note that on
@@ -581,7 +588,7 @@ ls -l ./x11vnc/x11vnc
documentation on how to use them?
[45]Q-7: I don't like typing arcane command line options every time I
- start x11vnc. What can I do? Is there a config file?
+ start x11vnc. What can I do? Is there a config file? Is there a GUI?
[46]Q-8: Why does x11vnc exit as soon as the VNC viewer disconnects?
And why doesn't it allow more than one VNC viewer to connect at the
@@ -623,133 +630,140 @@ ls -l ./x11vnc/x11vnc
[55]Q-17: How do I stop x11vnc once it is running in the background?
- [56]Q-18: Can I limit which machines incoming VNC clients can connect
+ [56]Q-18: Can I change settings in x11vnc without having to restart
+ it? Is there a way to remote control it?
+
+ [57]Q-19: Can I limit which machines incoming VNC clients can connect
from?
- [57]Q-19: How do I build x11vnc/libvncserver with libwrap
+ [58]Q-20: How do I build x11vnc/libvncserver with libwrap
(tcp_wrappers) support?
- [58]Q-20: Can I prompt the user at the local X display whether the
+ [59]Q-21: Can I prompt the user at the local X display whether the
incoming VNC client should be accepted or not? Can I decide to make
some clients view-only? How about running an arbitrary program to make
the decisions?
- [59]Q-21: How do I create a VNC password for use with x11vnc?
+ [60]Q-22: How do I create a VNC password for use with x11vnc?
- [60]Q-22: How can I tunnel my connection to x11vnc via an encrypted
+ [61]Q-23: How can I tunnel my connection to x11vnc via an encrypted
SSH channel between two Unix machines?
- [61]Q-23: How can I tunnel my connection to x11vnc via an encrypted
+ [62]Q-24: How can I tunnel my connection to x11vnc via an encrypted
SSH channel from Windows using an SSH client like Putty?
- [62]Q-24: Does x11vnc support Unix usernames and passwords? Can I
+ [63]Q-25: Does x11vnc support Unix usernames and passwords? Can I
further limit the set of Unix usernames who can connect to the VNC
desktop?
- [63]Q-25: Can I have two passwords for VNC viewers, one for full
+ [64]Q-26: Can I have two passwords for VNC viewers, one for full
access and the other for view-only access to the display?
- [64]Q-26: I use a screen-lock when I leave my workstation (e.g.
+ [65]Q-27: I use a screen-lock when I leave my workstation (e.g.
xscreensaver or xlock). When I remotely access my workstation desktop
via x11vnc I can unlock the desktop fine, but I am worried people will
see my activities on the physical monitor. What can I do to prevent
this, or at least make it more difficult?
- [65]Q-27: Can I have x11vnc automatically lock the screen when I
+ [66]Q-28: Can I have x11vnc automatically lock the screen when I
disconnect the VNC viewer?
- [66]Q-28: Are reverse connections (i.e. the VNC server connecting to
+ [67]Q-29: Are reverse connections (i.e. the VNC server connecting to
the VNC viewer) using "vncviewer -listen" and vncconnect(1) supported?
- [67]Q-29: Sometimes when a VNC viewer dies abruptly, x11vnc also dies
+ [68]Q-30: Sometimes when a VNC viewer dies abruptly, x11vnc also dies
with the error message like: "Broken pipe". I'm using the -forever
mode and I want x11vnc to keep running.
- [68]Q-30: How can I use x11vnc to connect to an X login screen like
+ [69]Q-31: How can I use x11vnc to connect to an X login screen like
xdm, GNOME gdm, KDE kdm, or CDE dtlogin? (i.e. nobody is logged into
an X session yet).
- [69]Q-31: Can I run x11vnc out of inetd(1)?
+ [70]Q-32: Can I run x11vnc out of inetd(1)?
- [70]Q-32: How do I make x11vnc work with the Java VNC viewer applet in
+ [71]Q-33: How do I make x11vnc work with the Java VNC viewer applet in
a web browser?
- [71]Q-33: Why isn't the mouse cursor shape (the little icon shape
+ [72]Q-34: Why isn't the mouse cursor shape (the little icon shape
where the mouse pointer is) correct as I move from window to window?
- [72]Q-34: Why does the mouse arrow just stay in one corner in my
+ [73]Q-35: Why does the mouse arrow just stay in one corner in my
vncviewer, whereas my cursor (that does move) is just a dot?
- [73]Q-35: Can I take advantage of the TightVNC extension to the VNC
+ [74]Q-36: Can I take advantage of the TightVNC extension to the VNC
protocol where Cursor Positions Updates are sent back to all connected
clients (i.e. passive viewers can see the mouse cursor being moved
around by another viewer)?
- [74]Q-36: Is it possible to swap the mouse buttons (e.g. left-handed
+ [75]Q-37: Is it possible to swap the mouse buttons (e.g. left-handed
operation), or arbitrarily remap them? How about mapping button clicks
to keystrokes, e.g. to partially emulate Mouse wheel scrolling?
- [75]Q-37: When I drag windows around with the mouse or scroll up and
+ [76]Q-38: When I drag windows around with the mouse or scroll up and
down things really bog down (unless I do the drag in a single, quick
motion). Is there anything to do to improve things?
- [76]Q-38: I have lots of memory, but why does x11vnc fail with
+ [77]Q-39: I have lots of memory, but why does x11vnc fail with
shmget: No space left on device or Minor opcode of failed
request: 1 (X_ShmAttach)?
- [77]Q-39: How can I make x11vnc use less system resources?
+ [78]Q-40: How can I make x11vnc use less system resources?
- [78]Q-40: How can I make x11vnc use MORE system resources?
+ [79]Q-41: How can I make x11vnc use MORE system resources?
- [79]Q-41: I use x11vnc over a slow link with high latency (e.g. dialup
+ [80]Q-42: I use x11vnc over a slow link with high latency (e.g. dialup
modem), is there anything I can do to speed things up?
- [80]Q-42: How can I get my AltGr and Shift modifiers to work between
+ [81]Q-43: How can I get my AltGr and Shift modifiers to work between
keyboards for different languages?
- [81]Q-43: When I try to type a "<" (i.e. less than) instead I get ">"
+ [82]Q-44: When I try to type a "<" (i.e. less than) instead I get ">"
(i.e. greater than)! Strangely, typing ">" works OK!!
- [82]Q-44: I'm using an "international" keyboard (e.g. German "de", or
+ [83]Q-45: I'm using an "international" keyboard (e.g. German "de", or
Danish "dk") and the -modtweak mode works well if the VNC viewer is
run on a Unix/Linux machine with a similar keyboard. But if I run the
VNC viewer on Unix/Linux with a different keyboard (e.g. "us") or
Windows with any keyboard, I can't type some keys like: "@", "$", "<",
">", etc. How can I fix this?
- [83]Q-45: When typing I sometimes get double, triple, or more of my
+ [84]Q-46: When typing I sometimes get double, triple, or more of my
keystrokes repeated. I'm sure I only typed them once, what can I do?
- [84]Q-46: The machine where I run x11vnc has an AltGr key, but the
+ [85]Q-47: The machine where I run x11vnc has an AltGr key, but the
local machine where I run the VNC viewer does not. Is there a way I
can map a local unused key to send an AltGr? How about a Compose key
as well?
- [85]Q-47: I have a Sun machine I run x11vnc on. Its Sun keyboard has
+ [86]Q-48: I have a Sun machine I run x11vnc on. Its Sun keyboard has
just one Alt key labelled "Alt" and two Meta keys labelled with little
diamonds. The machine where I run the VNC viewer only has Alt keys.
How can I send a Meta keypress? (e.g. emacs needs this)
- [86]Q-48: Can I map a keystroke to a mouse button click on the remote
+ [87]Q-49: Can I map a keystroke to a mouse button click on the remote
machine?
- [87]Q-49: The remote display is larger (in number of pixels) than the
+ [88]Q-50: The remote display is larger (in number of pixels) than the
local display I am running the vncviewer on. I don't like the
vncviewer scrollbars, what I can do?
- [88]Q-50: Does x11vnc support server-side framebuffer scaling? (E.g.
+ [89]Q-51: Does x11vnc support server-side framebuffer scaling? (E.g.
to make the desktop smaller).
- [89]Q-51: Does x11vnc work with Xinerama? (i.e. multiple monitors
+ [90]Q-52: Does x11vnc work with Xinerama? (i.e. multiple monitors
joined together to form one big, single screen).
- [90]Q-52: Can I use x11vnc on a multi-headed display that is not
+ [91]Q-53: Can I use x11vnc on a multi-headed display that is not
Xinerama (i.e. separate screens :0.0, :0.1, ... for each monitor)?
- [91]Q-53: Why is the view in my VNC viewer completely black? Or why is
+ [92]Q-54: Does x11vnc support the XRANDR (X Resize, Rotate and
+ Reflection) extension? Whenever I rotate or resize the screen x11vnc
+ just seems to crash.
+
+ [93]Q-55: Why is the view in my VNC viewer completely black? Or why is
everything flashing around randomly?
- [92]Q-54: I use Linux Virtual Consoles (VC's) to implement 'Fast User
+ [94]Q-56: I use Linux Virtual Consoles (VC's) to implement 'Fast User
Switching' between users' sessions (e.g. Betty is on Ctrl-Alt-F7,
Bobby is on Ctrl-Alt-F8, and Sid is on Ctrl-Alt-F1: they use those
keystrokes to switch between their sessions). How come the view in a
@@ -757,13 +771,13 @@ ls -l ./x11vnc/x11vnc
otherwise all messed up unless the X session x11vnc is attached to is
in the active VC?
- [93]Q-55: Does the Clipboard/Selection get transferred between the
+ [95]Q-57: Does the Clipboard/Selection get transferred between the
vncviewer and the X display?
- [94]Q-56: Why don't I hear the "Beeps" in my X session (e.g. when
+ [96]Q-58: Why don't I hear the "Beeps" in my X session (e.g. when
typing tput bel in an xterm)?
- [95]Q-57: I am using x11vnc where my local machine has "popup/hidden
+ [97]Q-59: I am using x11vnc where my local machine has "popup/hidden
taskbars" (e.g. GNOME or MacOS X) and the remote display where x11vnc
runs also has "popup/hidden taskbars" (e.g. GNOME). When I move the
mouse to the edge of the screen where the popups happen, the taskbars
@@ -863,7 +877,7 @@ ls -l ./x11vnc/x11vnc
is a workaround for Solaris 2.5.1 (and perhaps earlier):
First use the environment settings (CPPFLAGS, LDFLAGS, etc.) in the
- above [96]Solaris build script to run the configure command. That
+ above [98]Solaris build script to run the configure command. That
should succeed without failure. Then, you have to hand edit the
autogenerated rfb/rfbconfig.h file in the source tree, and just before
the last #endif at the bottom of that file insert these workaround
@@ -899,6 +913,10 @@ if (sym >> 8 == 0) { \
*(upper) -= (XK_oslash - XK_Ooblique); \
}
+ You will also have to change all the snprint() references to sprintf()
+ calls x11vnc.c (sorry I don't know how to do this in a macro since
+ snprint() is varargs).
+
Then run make with the Solaris build script environment, everything
should compile without problems, and the resulting x11vnc binary
should work OK (but note the above XConvertCase only covers Latin 1).
@@ -912,18 +930,18 @@ if (sym >> 8 == 0) { \
Q-4: Where can I get a precompiled x11vnc binary for my Operating
System?
- Hopefully the [97]build steps above and [98]FAQ provide enough info
+ Hopefully the [99]build steps above and [100]FAQ provide enough info
for a painless compile for most environments. Please report problems
with the x11vnc configure, make, etc. on your system (if your system
is known to compile other GNU packages successfully).
There are precompiled x11vnc binaries made by other groups available
at the following locations:
- Debian: (.deb) [99]http://packages.debian.org/x11vnc
+ Debian: (.deb) [101]http://packages.debian.org/x11vnc
- Slackware: (.tgz) [100]http://www.linuxpackages.net/ Redhat/Fedora:
- (.rpm) [101]http://dag.wieers.com/packages/x11vnc/ wwexptools: (.tgz)
- [102]http://www.bell-labs.com/project/wwexptools/packages.html The
+ Slackware: (.tgz) [102]http://www.linuxpackages.net/ Redhat/Fedora:
+ (.rpm) [103]http://dag.wieers.com/packages/x11vnc/ wwexptools: (.tgz)
+ [104]http://www.bell-labs.com/project/wwexptools/packages.html The
last one, wwexptools, provides a variety of Unix binaries (Linux,
Solaris, HP-UX, Irix, ...) with the intent of being compatible on a
wide range of OS releases. Find x11vnc near the bottom of that page
@@ -935,7 +953,7 @@ if (sym >> 8 == 0) { \
this by looking at the x11vnc output and if it says the encoding for a
client is "hextile" then likely the fast compression encodings are
missing. If you want optimal performance on your OS, you should see
- the [103]build notes above for where to download libz and libjpeg, and
+ the [105]build notes above for where to download libz and libjpeg, and
then build everything with gcc.
If any of the above binaries don't work and building x11vnc on your OS
@@ -949,8 +967,8 @@ if (sym >> 8 == 0) { \
above, the x11vnc binary from the above packages has a good chance of
working. You can "install" it by just copying the x11vnc binary to the
desired directory in your PATH. Tip on extracting files from a Debian
- package: extract the archive via a command like: ar x
- x11vnc_0.6-2_i386.deb and then you can find the binary in the
+ package: extract the archive via a command like: "ar x
+ x11vnc_0.6-2_i386.deb" and then you can find the binary in the
resulting data.tar.gz tar file. Also, rpm2cpio(1) is useful in
extracting files from rpm packages.
@@ -959,17 +977,17 @@ if (sym >> 8 == 0) { \
To obtain VNC viewers for the viewing side (Windows, Mac OS, or Unix)
try here:
- * [104]http://www.tightvnc.com/download.html
- * [105]http://www.realvnc.com/download-free.html
- * [106]http://sourceforge.net/projects/cotvnc/
+ * [106]http://www.tightvnc.com/download.html
+ * [107]http://www.realvnc.com/download-free.html
+ * [108]http://sourceforge.net/projects/cotvnc/
Q-6: How can I see all of x11vnc's command line options and
documentation on how to use them?
- Run: x11vnc -help The output is listed [107]here as well.
+ Run: x11vnc -help The output is listed [109]here as well.
Q-7: I don't like typing arcane command line options every time I
- start x11vnc. What can I do? Is there a config file?
+ start x11vnc. What can I do? Is there a config file? Is there a GUI?
You could create a shell script that calls x11vnc with your options:
#!/bin/sh
@@ -994,6 +1012,14 @@ display :0
At some point this config file support will be expanded.
+ As of Dec/2004 in the libvncserver CVS there is now a simple tcl/tk
+ GUI based on the remote-control functionality that was added. It's not
+ particulary user-friendly, it just provides a point and click mode to
+ set all the many x11vnc parameters and obtain help on them. See the
+ -gui for more info. Examples: "x11vnc ... -gui" and "x11vnc ... -gui
+ other:0" in the latter case the gui is displayed on other:0 not the X
+ display x11vnc is polling.
+
Q-8: Why does x11vnc exit as soon as the VNC viewer disconnects? And
why doesn't it allow more than one VNC viewer to connect at the same
time?
@@ -1005,10 +1031,12 @@ display :0
-shared option to have x11vnc allow multiple clients to connect
simultaneously.
- Recommended additional safety measures include using ssh ([108]see
+ Recommended additional safety measures include using ssh ([110]see
above), stunnel, or a VPN to authenticate and encrypt the viewer
- connections or to at least use the -rfbauth passwd-file [109]option to
- use VNC password protection (or [110]-passwdfile)
+ connections or to at least use the -rfbauth passwd-file [111]option to
+ use VNC password protection (or [112]-passwdfile) It is up to you to
+ apply these security measures, they will not be done for you
+ automatically.
Q-9: I have two separate machine displays in front of me, one Windows
the other X11: can I use x11vnc in combination with Win2VNC in
@@ -1020,16 +1048,16 @@ display :0
secondary display (X11). Then start up Win2VNC on the primary display
(Windows) referring it to the secondary display.
- This will also work X11 to X11 using [111]x2vnc, however you would
+ This will also work X11 to X11 using [113]x2vnc, however you would
probably just want to avoid VNC and use x2x for that.
For reference, here are some links to Win2VNC-like programs for
multiple monitor setups:
- * [112]Original Win2VNC
- * [113]Enhanced Win2VNC and [114]sourceforge link
- * [115]x2vnc
- * [116]x2x also [117]here
- * [118]zvnc (MorphOS)
+ * [114]Original Win2VNC
+ * [115]Enhanced Win2VNC and [116]sourceforge link
+ * [117]x2vnc
+ * [118]x2x also [119]here
+ * [120]zvnc (MorphOS)
All of them (except x2x) will work with x11vnc.
@@ -1083,7 +1111,7 @@ display :0
visuals of different color depths: e.g. there are both depth 8 and 24
visuals available at the same time.
- You may want to review the [119]previous question regarding 8 bpp
+ You may want to review the [121]previous question regarding 8 bpp
PseudoColor.
If that isn't the problem, run xdpyinfo(1) to see what the default
@@ -1118,12 +1146,13 @@ TrueColor defdepth 24
Another option is if the system with overlay visuals is a Sun system
running Solaris you can use the -overlay x11vnc option (Aug/2004) to
have x11vnc use the Solaris XReadScreen(3X11) function to poll the
- "true view" of the whole screen at depth 24 TrueColor. This is useful
+ "true view" of the whole screen at depth 24 TrueColor.This is useful
for Legacy applications (older versions of Cadence CAD apps are
mentioned by x11vnc users) that require the default depth be 8bpp, or
will use a 8bpp visual even if depth 24 visuals are available, and so
the default depth workaround described in the previous paragraph is
- not sufficient for these apps.
+ not sufficient for these apps. The -overlay mode should also work on
+ IRIX machines.
Misc. notes on -overlay mode: An amusing by-product of -overlay mode
is that mouse cursor shape is correct. The -overlay mode may be
@@ -1154,12 +1183,17 @@ TrueColor defdepth 24
the desired application window. After clicking, it will print out much
information, including the window id. Also, the visual and depth of
the window printed out is often useful in debugging x11vnc
- [120]problems.
+ [122]problems.
When using -id windowid, note that some VNC viewers will have problems
rendering screens that have a width that is not a multiple of 4. Try
to manually adjust the window width before starting x11vnc -id ....
+ Also, as of Dec/2004 libvncserver CVS you can use "-id pick" to have
+ x11vnc run xwininfo(1) for you and after you click the window it
+ extracts the windowid. Besides "pick" there is also "root" to allow
+ you to go back to root window when doing remote-control.
+
Q-14: Why don't menus or other transient windows come up when I am
using the -id windowid option to view a single application window?
@@ -1168,12 +1202,14 @@ TrueColor defdepth 24
way the image is retrieved depends on some aspects of how the X server
maintains the display image data and whether other windows are
clipping or obscuring it. See the XGetImage man page for more details.
+ If you disable BackingStore and SaveUnders in the X server you should
+ be able to see these transient windows.
If things are not working and you still want to do the single window
polling, try the -sid windowid option ("shifted" windowid).
x11vnc is known to crash under both -id and -sid, so both modes are
- still experimental.
+ still experimental. Please report any reproducible bugs.
Q-15: Can I use x11vnc to view and interact with an Xterminal (e.g.
NCD) that is not running UNIX and so x11vnc cannot be run on it
@@ -1206,9 +1242,10 @@ TrueColor defdepth 24
If the -forever option has not been supplied, x11vnc will
automatically exit after the first client disconnects. In general you
- will have to kill the x11vnc process. This can be done via: "kill
- NNNNN" (where NNNNN is the x11vnc process id number found from ps(1)),
- or "pkill x11vnc", or "killall x11vnc" (Linux only, IIRC).
+ will have to kill the x11vnc process (however, see the remote-control
+ -R option below). This can be done via: "kill NNNNN" (where NNNNN is
+ the x11vnc process id number found from ps(1)), or "pkill x11vnc", or
+ "killall x11vnc" (Linux only, IIRC).
If you have not put x11vnc in the background via the -bg option or
shell & operator, then simply press Ctrl-C in the shell where x11vnc
@@ -1221,7 +1258,29 @@ TrueColor defdepth 24
Ctrl, Shift, and Alt. Alternatively, the -clear_mods and -clear_keys
options can be used to release pressed keys at startup and exit.
- Q-18: Can I limit which machines incoming VNC clients can connect
+ As of Dec/2004 in the libvncserver CVS there is a remote control
+ feature. It can change a huge amount of things on the fly: see the
+ -remote and -query options. To shut down the running x11vnc server
+ just type "x11vnc -R stop". To disconnect all clients do "x11vnc -R
+ disconnect:all", etc.
+
+ Q-18: Can I change settings in x11vnc without having to restart it? Is
+ there a way to remote control it?
+
+ Look at the -remote (same as -R) and -query (same as -Q) options added
+ in the Dec/2004 libvncserver CVS. They allow nearly everything to be
+ changed dynamically and settings to be queried. Examples: "x11vnc -R
+ shared", "x11vnc -R forever", "x11vnc -R scale:3/4", "x11vnc -Q
+ modtweak", "x11vnc -R stop", "x11vnc -R disconnect:all", etc.. These
+ commands do not start a x11vnc server, but rather communicate with one
+ that is already running. The X display (VNC_CONNECT property) is used
+ as the communication channel, so the X permissions and DISPLAY must be
+ set up correctly.
+
+ There is also a simple tcl/tk gui based on this remote control
+ mechanism. See the -gui option for more info.
+
+ Q-19: Can I limit which machines incoming VNC clients can connect
from?
Yes, look at the -allow and -localhost options to limit connections by
@@ -1231,12 +1290,13 @@ TrueColor defdepth 24
for those two hosts or
x11vnc -allow 192.168.0.
- for a subnet. Note that -localhost is the same as "-allow 127.0.0.1"
+ for a subnet. For individual hosts you can use the hostname instead of
+ the IP number. Note that -localhost is the same as "-allow 127.0.0.1"
For more control, build libvncserver with libwrap support
(tcp_wrappers) and then use /etc/hosts.allow.
- Q-19: How do I build x11vnc/libvncserver with libwrap (tcp_wrappers)
+ Q-20: How do I build x11vnc/libvncserver with libwrap (tcp_wrappers)
support?
Here is one way to pass this information to the configure script:
@@ -1251,11 +1311,11 @@ TrueColor defdepth 24
is "vnc", e.g.:
vnc: 192.168.100.3 .example.com
- Note that if you run x11vnc out of [121]inetd you do not need to build
+ Note that if you run x11vnc out of [123]inetd you do not need to build
x11vnc with libwrap support because the /usr/sbin/tcpd reference in
/etc/inetd.conf handles the tcp_wrappers stuff.
- Q-20: Can I prompt the user at the local X display whether the
+ Q-21: Can I prompt the user at the local X display whether the
incoming VNC client should be accepted or not? Can I decide to make
some clients view-only? How about running an arbitrary program to make
the decisions?
@@ -1273,7 +1333,7 @@ TrueColor defdepth 24
of the X11 display being polled. Also, RFB_X11VNC_PID is set to the
x11vnc process id (e.g. in case you decided to kill it), RFB_CLIENT_ID
will be an id number, and RFB_CLIENT_COUNT the number of other clients
- currently connected.
+ currently connected. RFB_MODE will be "accept".
As a special case, "-accept popup" will instruct x11vnc to create its
own simple popup window. To accept the client press "y" or click mouse
@@ -1295,7 +1355,7 @@ TrueColor defdepth 24
program to prompt the user whether the client should be accepted or
not. This requires that you have xmessage installed and available via
PATH. In case it is not already on your system, the xmessage program
- is available at [122]ftp://ftp.x.org/
+ is available at [124]ftp://ftp.x.org/
To include view-only decisions for the external commands, prefix the
command something like this: "yes:0,no:*,view:3 mycommand ..." This
@@ -1334,7 +1394,7 @@ elif [ $rc = 4 ]; then
fi
exit 1
- Stefan Radman has written a nice dtksh script [123]dtVncPopup for use
+ Stefan Radman has written a nice dtksh script [125]dtVncPopup for use
in CDE environments to do the same sort of thing. Information on how
to use it is found at the top of the file. He encourages you to
provide feedback to him to help improve the script.
@@ -1347,9 +1407,10 @@ exit 1
To run a command when a client disconnects, use the "-gone command"
option. This is for the user's convenience only: the return code of
the command is not interpreted by x11vnc. The same environment
- variables are set as in "-accept command"
+ variables are set as in "-accept command" (except that RFB_MODE will
+ be "gone").
- Q-21: How do I create a VNC password for use with x11vnc?
+ Q-22: How do I create a VNC password for use with x11vnc?
You may already have one in $HOME/.vnc/passwd if you have used, say,
the vncserver program from the regular RealVNC or TightVNC packages
@@ -1369,24 +1430,24 @@ exit 1
out for the command winding up in your shell's history file (history
-c is often a way to clear it).
- x11vnc also has the [124]-passwdfile and -passwd/-viewpasswd plain
+ x11vnc also has the [126]-passwdfile and -passwd/-viewpasswd plain
text (i.e. not obscured like the -rfbauth VNC passwords) password
options.
- Q-22: How can I tunnel my connection to x11vnc via an encrypted SSH
+ Q-23: How can I tunnel my connection to x11vnc via an encrypted SSH
channel between two Unix machines?
- See the description earlier on this page on [125]how to tunnel VNC via
+ See the description earlier on this page on [127]how to tunnel VNC via
SSH from Unix to Unix. A number of ways are described along with some
issues you may encounter.
Other secure encrypted methods exists, e.g. stunnel, IPSEC, various
VPNs, etc.
- Q-23: How can I tunnel my connection to x11vnc via an encrypted SSH
+ Q-24: How can I tunnel my connection to x11vnc via an encrypted SSH
channel from Windows using an SSH client like Putty?
- [126]Above we described how to tunnel VNC via SSH from Unix to Unix,
+ [128]Above we described how to tunnel VNC via SSH from Unix to Unix,
you may want to review it. To do this from Windows using Putty it
would go something like this:
* In the Putty dialog window under 'Session' enter the hostname or
@@ -1419,14 +1480,14 @@ exit 1
you'll need to do a second login (ssh or rsh) to the workstation
machine 'otherhost' and then start up x11vnc on it.
- As discussed [127]above another option is to first start the VNC
+ As discussed [129]above another option is to first start the VNC
viewer in "listen" mode, and then launch x11vnc with the "-connection
localhost" option to establish the reverse connection. In this case a
Remote port redirection (not Local) is needed for port 5500 instead of
5900 (i.e. 'Source port: 5500' and 'Destination: localhost:5500' for
a Remote connection).
- Q-24: Does x11vnc support Unix usernames and passwords? Can I further
+ Q-25: Does x11vnc support Unix usernames and passwords? Can I further
limit the set of Unix usernames who can connect to the VNC desktop?
Until the VNC protocol and libvncserver support this things will be
@@ -1440,7 +1501,7 @@ exit 1
connection to make it appear to emanate from the local machine. As
discussed above, ssh is useful for this: ssh -l username -L
5900:localhost:5900 hostname ... See the ssh wrapper scripts mentioned
- [128]elsewhere on this page. Of course a malicious user could allow
+ [130]elsewhere on this page. Of course a malicious user could allow
other users to get in through his channel, but that is a problem with
every method. Another thing to watch out for is a malicious user on
the viewer side (where ssh is running) trying to sneak in through the
@@ -1477,7 +1538,7 @@ exit 1 # reject it
For this to work with ssh port redirection, the ssh option
UsePrivilegeSeparation must be enabled.
- Q-25: Can I have two passwords for VNC viewers, one for full access
+ Q-26: Can I have two passwords for VNC viewers, one for full access
and the other for view-only access to the display?
Yes, as of May/2004 in the libvncserver CVS there is the -viewpasswd
@@ -1503,7 +1564,7 @@ exit 1 # reject it
plain text passwords from $HOME/.vnc/passwd since it is very
straight-forward to work out what to do from the VNC source code.
- Q-26: I use a screen-lock when I leave my workstation (e.g.
+ Q-27: I use a screen-lock when I leave my workstation (e.g.
xscreensaver or xlock). When I remotely access my workstation desktop
via x11vnc I can unlock the desktop fine, but I am worried people will
see my activities on the physical monitor. What can I do to prevent
@@ -1516,7 +1577,7 @@ exit 1 # reject it
In any event, as of Jun/2004 there is an experimental utility to make
it more difficult for nosey people to see your x11vnc activities. The
- source for it is [129]blockdpy.c The idea behind it is simple (but
+ source for it is [131]blockdpy.c The idea behind it is simple (but
obviously not bulletproof): when a VNC client attaches to x11vnc put
the display monitor in the DPMS "off" state, if the DPMS state ever
changes immediately start up the screen-lock program. The x11vnc user
@@ -1537,7 +1598,7 @@ exit 1 # reject it
re-lock the screen before disconnecting!). Instructions can be found
in the source code for the utility at the above link.
- Q-27: Can I have x11vnc automatically lock the screen when I
+ Q-28: Can I have x11vnc automatically lock the screen when I
disconnect the VNC viewer?
Yes, a user mentions he uses the -gone option under CDE to run a
@@ -1549,7 +1610,7 @@ exit 1 # reject it
x11vnc -display :0.0 -forever -gone 'kdesktop_lock'
x11vnc -display :0.0 -forever -gone 'xlock &'
- Q-28: Are reverse connections (i.e. the VNC server connecting to the
+ Q-29: Are reverse connections (i.e. the VNC server connecting to the
VNC viewer) using "vncviewer -listen" and vncconnect(1) supported?
As of Mar/2004 in the libvncserver CVS x11vnc supports reverse
@@ -1562,12 +1623,12 @@ exit 1 # reject it
periodically (about once a second) for new hosts to connect to.
To use the vncconnect(1) program (from the core VNC package at
- www.realvnc.com) specify the -vncconnect option to x11vnc.
- vncconnect(1) must be pointed to the same X11 DISPLAY as x11vnc (since
- it uses X properties to communicate with x11vnc). If you do not have
- or do not want to get the vncconnect(1) program, the following script
- (named "Vncconnect") may work if your xprop(1) supports the -set
- option:
+ www.realvnc.com) specify the -vncconnect option to x11vnc (Note: as of
+ Dec/2004 -vncconnect is now the default). vncconnect(1) must be
+ pointed to the same X11 DISPLAY as x11vnc (since it uses X properties
+ to communicate with x11vnc). If you do not have or do not want to get
+ the vncconnect(1) program, the following script (named "Vncconnect")
+ may work if your xprop(1) supports the -set option:
#!/bin/sh
# usage: Vncconnect <host>
# Vncconnect <host:port>
@@ -1575,7 +1636,7 @@ exit 1 # reject it
#
xprop -root -f VNC_CONNECT 8s -set VNC_CONNECT "$1"
- Q-29: Sometimes when a VNC viewer dies abruptly, x11vnc also dies with
+ Q-30: Sometimes when a VNC viewer dies abruptly, x11vnc also dies with
the error message like: "Broken pipe". I'm using the -forever mode and
I want x11vnc to keep running.
@@ -1583,12 +1644,12 @@ xprop -root -f VNC_CONNECT 8s -set VNC_CONNECT "$1"
So if a viewer client terminates abruptly, libvncserver will notice on
the next I/O operation and will close the connection and continue on.
- Currently (Apr/2004) the above fix only works for BSD signal systems
- (Linux, FreeBSD, ...) For SYSV systems there is a workaround in my
- [130]x11vnc.c file. It also has an option -sigpipe exit to have x11vnc
+ As of Apr/2004 the above fix only works for BSD signal systems (Linux,
+ FreeBSD, ...) For SYSV systems there is a workaround in my
+ [132]x11vnc.c file. It also has an option -sigpipe exit to have x11vnc
clean up and exit upon receiving SIGPIPE.
- Q-30: How can I use x11vnc to connect to an X login screen like xdm,
+ Q-31: How can I use x11vnc to connect to an X login screen like xdm,
GNOME gdm, KDE kdm, or CDE dtlogin? (i.e. nobody is logged into an X
session yet).
@@ -1654,7 +1715,7 @@ xprop -root -f VNC_CONNECT 8s -set VNC_CONNECT "$1"
If you do not want to deal with the display manager startup scripts,
here is a kludgey script that can be run manually or out of a boot
- file like rc.local. [131]x11vnc_loop It will need some local
+ file like rc.local. [133]x11vnc_loop It will need some local
customization before running. Because the XAUTHORITY auth file must be
guessed by this script, use of the display manager script above is
preferred.
@@ -1677,7 +1738,7 @@ xprop -root -f VNC_CONNECT 8s -set VNC_CONNECT "$1"
See xauth(1) manpage for full details on how to transfer an
MIT-MAGIC-COOKIE between machines and displays.
- Q-31: Can I run x11vnc out of inetd(1)?
+ Q-32: Can I run x11vnc out of inetd(1)?
Yes, perhaps a line something like this in /etc/inetd.conf will do it
for you:
@@ -1723,7 +1784,7 @@ mp/x11vnc_sh.log
connecting to it. Always use a VNC password to further protect against
unwanted access.
- Q-32: How do I make x11vnc work with the Java VNC viewer applet in a
+ Q-33: How do I make x11vnc work with the Java VNC viewer applet in a
web browser?
To have x11vnc serve up a Java VNC viewer applet to any web browsers
@@ -1750,7 +1811,7 @@ mp/x11vnc_sh.log
entirely from the viewer-side by having the jar file there and using
either the java or appletviewer commands to run the program.
- Q-33: Why isn't the mouse cursor shape (the little icon shape where
+ Q-34: Why isn't the mouse cursor shape (the little icon shape where
the mouse pointer is) correct as I move from window to window?
As mentioned above, the X11 mouse cursor shape (i.e. little picture:
@@ -1774,13 +1835,18 @@ mp/x11vnc_sh.log
Also note that as of Aug/2004 in the libvncserver CVS, on Solaris
using the SUN_OVL overlay extension, x11vnc can show the correct mouse
cursor when the -overlay is also supplied. (-overlay has some other
- problems however, and can be slower). Plans are in the works to use
- XFIXES for this on XFree86, Xorg, and Xsun.
-
- Q-34: Why does the mouse arrow just stay in one corner in my
+ problems however, and can be slower). Also as of Dec/2004 in
+ libvncserver CVS XFIXES X extension support has been added to allow
+ exact extraction of the mouse cursor shape. This is the preferred way
+ of viewing the cursor shape, it is available on recent Linux Xorg
+ based distros and Solaris 10 express (on Solaris you will need to add
+ "-L /usr/openwin/sfw/lib -R /usr/openwin/sfw/lib" to LDFLAGS for
+ configure to enable it).
+
+ Q-35: Why does the mouse arrow just stay in one corner in my
vncviewer, whereas my cursor (that does move) is just a dot?
- This default takes advantage of a [132]tightvnc extension that allows
+ This default takes advantage of a [134]tightvnc extension that allows
specifying a cursor image for the local VNC viewer. You may disable it
with the -nocursor option to x11vnc if your viewer does not have this
extension.
@@ -1789,7 +1855,7 @@ mp/x11vnc_sh.log
default for non-tightvnc viewers will be to draw the moving cursor
into the framebuffer. This can also be disabled via -nocursor.
- Q-35: Can I take advantage of the TightVNC extension to the VNC
+ Q-36: Can I take advantage of the TightVNC extension to the VNC
protocol where Cursor Positions Updates are sent back to all connected
clients (i.e. passive viewers can see the mouse cursor being moved
around by another viewer)?
@@ -1800,7 +1866,7 @@ mp/x11vnc_sh.log
libvncserver CVS -cursorpos is the default. See -nocursorpos and
-nocursorshape.
- Q-36: Is it possible to swap the mouse buttons (e.g. left-handed
+ Q-37: Is it possible to swap the mouse buttons (e.g. left-handed
operation), or arbitrarily remap them? How about mapping button clicks
to keystrokes, e.g. to partially emulate Mouse wheel scrolling?
@@ -1849,7 +1915,7 @@ mp/x11vnc_sh.log
(yes, this is getting a little silly).
- Q-37: When I drag windows around with the mouse or scroll up and down
+ Q-38: When I drag windows around with the mouse or scroll up and down
things really bog down (unless I do the drag in a single, quick
motion). Is there anything to do to improve things?
@@ -1865,7 +1931,11 @@ mp/x11vnc_sh.log
some circumstances when you want to see the visual feedback while
dragging (e.g. menu traversal or text selection).
- Q-38: I have lots of memory, but why does x11vnc fail with shmget:
+ As of Dec/2004 in the libvncserver CVS the -pointer_mode n option was
+ introduced. n=1 is the -old_pointer. See the -pointer_mode n help for
+ more info.
+
+ Q-39: I have lots of memory, but why does x11vnc fail with shmget:
No space left on device or Minor opcode of failed request: 1
(X_ShmAttach)?
@@ -1883,7 +1953,7 @@ mp/x11vnc_sh.log
19/03/2004 10:10:58 error creating tile-row shm for len=4
19/03/2004 10:10:58 reverting to single_copytile mode
- Here is a shell script [133]shm_clear to list and prompt for removal
+ Here is a shell script [135]shm_clear to list and prompt for removal
of your unattached shm segments (attached ones are skipped). I use it
while debugging x11vnc (I use shm_clear -y to assume "yes" for each
prompt). If x11vnc is regularly not cleaning up its shm segments,
@@ -1921,10 +1991,10 @@ ied)
-fs 1.0 knocks it down to 2). If you are having much trouble with shm
segments, consider disabling shm completely via the -noshm option.
Performance will be somewhat degraded but when done over local machine
- sockets it should be acceptable (see an [134]earlier question
+ sockets it should be acceptable (see an [136]earlier question
discussing -noshm).
- Q-39: How can I make x11vnc use less system resources?
+ Q-40: How can I make x11vnc use less system resources?
The -nap and "-wait n" (where n is the sleep between polls in
milliseconds, the default is 30 or so) option are good places to
@@ -1933,7 +2003,7 @@ ied)
-onetile option will use less memory and use fewer shared memory slots
(add -fs 1.0 for one less slot).
- Q-40: How can I make x11vnc use MORE system resources?
+ Q-41: How can I make x11vnc use MORE system resources?
You can try -threads and dial down the wait time (e.g. -wait 1) and
possibly dial down -defer as well. Note that if you try to increase
@@ -1945,7 +2015,7 @@ ied)
the x11vnc -id option) can be streamed over a LAN or wireless at a
reasonable frame rate.
- Q-41: I use x11vnc over a slow link with high latency (e.g. dialup
+ Q-42: I use x11vnc over a slow link with high latency (e.g. dialup
modem), is there anything I can do to speed things up?
Some things you might want to experiment with (most of which will help
@@ -1969,7 +2039,7 @@ ied)
worth it, but could be of use in some situations.
VNC viewer parameters:
- * Use a [135]TightVNC enabled viewer!
+ * Use a [137]TightVNC enabled viewer!
* Make sure the tight encoding is being used (look at vncviewer and
x11vnc outputs)
* Request 8 bits per pixel using -bgr233 (up to 4X speedup over
@@ -2005,7 +2075,7 @@ ied)
* Use -nocursor (repainting the remote cursor position and shape
takes resources and round trips)
- Q-42: How can I get my AltGr and Shift modifiers to work between
+ Q-43: How can I get my AltGr and Shift modifiers to work between
keyboards for different languages?
The option -modtweak should be of some use for this. It is a mode that
@@ -2017,12 +2087,12 @@ ied)
default (use -nomodtweak to get the old behavior). This was done
because it was noticed on newer XFree86 setups even on bland "us"
keyboards like "pc104 us" XFree86 included a "ghost" key with both "<"
- and ">" it. This key does not exist on the keyboard (see [136]this FAQ
+ and ">" it. This key does not exist on the keyboard (see [138]this FAQ
for more info). Without -modtweak there was then an ambiguity in the
reverse map keysym => keycode, making it so the "<" symbol could not
be typed.
- Also see the [137]FAQ about the -xkb option for a more powerful method
+ Also see the [139]FAQ about the -xkb option for a more powerful method
of modifier tweaking for use on X servers with the XKEYBOARD
extension.
@@ -2030,7 +2100,7 @@ ied)
-debug_keyboard option prints out much info for every keystroke and so
can be useful debugging things.
- Q-43: When I try to type a "<" (i.e. less than) instead I get ">"
+ Q-44: When I try to type a "<" (i.e. less than) instead I get ">"
(i.e. greater than)! Strangely, typing ">" works OK!!
Does your keyboard have a single key with both "<" and ">" on it? Even
@@ -2083,14 +2153,14 @@ ied)
the keysym comma when it comes in from a client (so when Shift is down
the comma press will yield "<").
- See also the [138]FAQ about the -xkb option as a possible workaround
+ See also the [140]FAQ about the -xkb option as a possible workaround
using the XKEYBOARD extension. Note that of Jul/2004 in the
libvncserver CVS the -modtweak option is now that default.
Note that the -debug_keyboard option prints out much info for every
keystroke to aid debugging keyboard problems.
- Q-44: I'm using an "international" keyboard (e.g. German "de", or
+ Q-45: I'm using an "international" keyboard (e.g. German "de", or
Danish "dk") and the -modtweak mode works well if the VNC viewer is
run on a Unix/Linux machine with a similar keyboard. But if I run the
VNC viewer on Unix/Linux with a different keyboard (e.g. "us") or
@@ -2178,7 +2248,7 @@ ied)
is received from a VNC viewer, and only after that would
-add_keysyms, or anything else, come into play.
- Q-45: When typing I sometimes get double, triple, or more of my
+ Q-46: When typing I sometimes get double, triple, or more of my
keystrokes repeated. I'm sure I only typed them once, what can I do?
This may be due to an interplay between your X server's key autorepeat
@@ -2188,6 +2258,8 @@ ied)
off" on the Xserver where x11vnc is run (restore via "xset r on") or
use the new (Jul/2004) -norepeat x11vnc option. You will still have
autorepeating because that is taken care of on your VNC viewer side.
+ Update: as of Dec/2004 -norepeat is now the default. Use -repeat to
+ disable it.
Details: suppose you press a key DOWN and it generates changes in
large regions of the screen. The CPU and I/O work x11vnc does for the
@@ -2216,7 +2288,7 @@ ied)
someone is also working at the physical display and misses his
autorepeating.
- Q-46: The machine where I run x11vnc has an AltGr key, but the local
+ Q-47: The machine where I run x11vnc has an AltGr key, but the local
machine where I run the VNC viewer does not. Is there a way I can map
a local unused key to send an AltGr? How about a Compose key as well?
@@ -2230,7 +2302,7 @@ ied)
Super_R-Mode_switch,Menu-Multi_key" or use "-remap filename" to
specify remappings from a file.
- Q-47: I have a Sun machine I run x11vnc on. Its Sun keyboard has just
+ Q-48: I have a Sun machine I run x11vnc on. Its Sun keyboard has just
one Alt key labelled "Alt" and two Meta keys labelled with little
diamonds. The machine where I run the VNC viewer only has Alt keys.
How can I send a Meta keypress? (e.g. emacs needs this)
@@ -2247,7 +2319,7 @@ ied)
send Alt_L in this case, maybe -remap Super_L-Meta_L would be a better
choice.
- Q-48: Can I map a keystroke to a mouse button click on the remote
+ Q-49: Can I map a keystroke to a mouse button click on the remote
machine?
This can be done directly in some X servers using AccessX and
@@ -2269,7 +2341,7 @@ ied)
are generated immediately on the x11vnc side. When the key is released
(i.e. goes up) no events are generated.
- Q-49: The remote display is larger (in number of pixels) than the
+ Q-50: The remote display is larger (in number of pixels) than the
local display I am running the vncviewer on. I don't like the
vncviewer scrollbars, what I can do?
@@ -2287,10 +2359,10 @@ ied)
There may also be scaling viewers out there (e.g. TightVNC on Windows)
that automatically shrink or expand the remote framebuffer to fit the
- local display. Especially for hand-held devices. See also [139]this
+ local display. Especially for hand-held devices. See also [141]this
FAQ
- Q-50: Does x11vnc support server-side framebuffer scaling? (E.g. to
+ Q-51: Does x11vnc support server-side framebuffer scaling? (E.g. to
make the desktop smaller).
As of Jun/2004 in the libvncserver CVS x11vnc provides basic
@@ -2337,7 +2409,7 @@ ied)
different scalings listening on separate ports (-rfbport option,
etc.).
- Q-51: Does x11vnc work with Xinerama? (i.e. multiple monitors joined
+ Q-52: Does x11vnc work with Xinerama? (i.e. multiple monitors joined
together to form one big, single screen).
Yes, it should generally work because it simply polls the big
@@ -2364,7 +2436,7 @@ ied)
function. (This may be due to a bug in the X server for XTEST when
Xinerama is enabled).
- Q-52: Can I use x11vnc on a multi-headed display that is not Xinerama
+ Q-53: Can I use x11vnc on a multi-headed display that is not Xinerama
(i.e. separate screens :0.0, :0.1, ... for each monitor)?
You can, but it is a little bit awkward: you must start separate
@@ -2382,17 +2454,37 @@ ied)
Note: if you are running on Solaris 8 or earlier you can easily hit up
against the maximum of 6 shm segments per process (for Xsun in this
case) from running multiple x11vnc processes. You should modify
- /etc/system as mentioned in another [140]FAQ to increase the limit. It
+ /etc/system as mentioned in another [142]FAQ to increase the limit. It
is probably also a good idea to run with the -onetile option in this
case (to limit each x11vnc to 3 shm segments), or even -noshm to use
no shm segments.
- Q-53: Why is the view in my VNC viewer completely black? Or why is
+ Q-54: Does x11vnc support the XRANDR (X Resize, Rotate and Reflection)
+ extension? Whenever I rotate or resize the screen x11vnc just seems to
+ crash.
+
+ As of Dec/2004 in the libvncserver CVS x11vnc supports XRANDR. You
+ enable it with the -xrandr option to make x11vnc monitor XRANDR events
+ and also trap X server errors if the screen change occurred in the
+ middle of an X call like XGetImage. Once it traps the screen change it
+ will create a new framebuffer using the new screen. If the connected
+ vnc viewers support the NewFBSize VNC extension (Windows TightVNC
+ viewer and RealVNC 4.0 windows and Unix viewers do) then the viewer
+ will automatically resize. Otherwise, the new framebuffer is fit as
+ best as possible into the original viewer size (portions of the screen
+ may be clipped, unused, etc).
+
+ If you specify "-xrandr newfbsize" then vnc viewers that do not
+ support NewFBSize will be disconnected before the resize. If you
+ specify "-xrandr exit" then all will be disconnected and x11vnc will
+ terminate.
+
+ Q-55: Why is the view in my VNC viewer completely black? Or why is
everything flashing around randomly?
See the next FAQ for a possible explanation.
- Q-54: I use Linux Virtual Consoles (VC's) to implement 'Fast User
+ Q-56: I use Linux Virtual Consoles (VC's) to implement 'Fast User
Switching' between users' sessions (e.g. Betty is on Ctrl-Alt-F7,
Bobby is on Ctrl-Alt-F8, and Sid is on Ctrl-Alt-F1: they use those
keystrokes to switch between their sessions). How come the view in a
@@ -2419,7 +2511,7 @@ ied)
x11vnc can poll it), one can use the switchto(1) command, e.g.
"switchto 7" for VC #7.
- Q-55: Does the Clipboard/Selection get transferred between the
+ Q-57: Does the Clipboard/Selection get transferred between the
vncviewer and the X display?
As of Jan/2004 in the libvncserver CVS x11vnc supports the "CutText"
@@ -2429,7 +2521,7 @@ ied)
want the PRIMARY selection to be polled for changes use the -noprimary
option.
- Q-56: Why don't I hear the "Beeps" in my X session (e.g. when typing
+ Q-58: Why don't I hear the "Beeps" in my X session (e.g. when typing
tput bel in an xterm)?
As of Dec/2003 in the libvncserver CVS "Beep" XBell events are tracked
@@ -2441,7 +2533,7 @@ ied)
want to hear the audio from the remote applications, consider trying a
redirector such as esd.
- Q-57: I am using x11vnc where my local machine has "popup/hidden
+ Q-59: I am using x11vnc where my local machine has "popup/hidden
taskbars" (e.g. GNOME or MacOS X) and the remote display where x11vnc
runs also has "popup/hidden taskbars" (e.g. GNOME). When I move the
mouse to the edge of the screen where the popups happen, the taskbars
@@ -2550,51 +2642,53 @@ References
93. http://www.karlrunge.com/x11vnc/index.html#FAQ-55
94. http://www.karlrunge.com/x11vnc/index.html#FAQ-56
95. http://www.karlrunge.com/x11vnc/index.html#FAQ-57
- 96. http://www.karlrunge.com/x11vnc/index.html#solarisbuilding
- 97. http://www.karlrunge.com/x11vnc/index.html#building
- 98. http://www.karlrunge.com/x11vnc/index.html#buildfaq
- 99. http://packages.debian.org/x11vnc
- 100. http://www.linuxpackages.net/search_view.php?by=name&name=x11vnc
- 101. http://dag.wieers.com/packages/x11vnc/
- 102. http://www.bell-labs.com/project/wwexptools/packages.html
- 103. http://www.karlrunge.com/x11vnc/index.html#solarisbuilding
- 104. http://www.tightvnc.com/download.html
- 105. http://www.realvnc.com/download-free.html
- 106. http://sourceforge.net/projects/cotvnc/
- 107. http://www.karlrunge.com/x11vnc/x11vnc_opts.html
- 108. http://www.karlrunge.com/x11vnc/index.html#tunnelling
- 109. http://www.karlrunge.com/x11vnc/index.html#passwd
- 110. http://www.karlrunge.com/x11vnc/index.html#passwdfile
- 111. http://fredrik.hubbe.net/x2vnc.html
- 112. http://www.hubbe.net/~hubbe/win2vnc.html
- 113. http://www.deboer.gmxhome.de/
- 114. http://sourceforge.net/projects/win2vnc/
- 115. http://fredrik.hubbe.net/x2vnc.html
- 116. http://freshmeat.net/projects/x2x/
- 117. http://ftp.digital.com/pub/Digital/SRC/x2x/
- 118. http://zapek.com/software/zvnc/
- 119. http://www.karlrunge.com/x11vnc/index.html#8bpp
- 120. http://www.karlrunge.com/x11vnc/index.html#overlays
- 121. http://www.karlrunge.com/x11vnc/index.html#inetd
- 122. ftp://ftp.x.org/
- 123. http://www.karlrunge.com/x11vnc/dtVncPopup
- 124. http://www.karlrunge.com/x11vnc/index.html#passwdfile
- 125. http://www.karlrunge.com/x11vnc/index.html#tunnelling
- 126. http://www.karlrunge.com/x11vnc/index.html#tunnelling
+ 96. http://www.karlrunge.com/x11vnc/index.html#FAQ-58
+ 97. http://www.karlrunge.com/x11vnc/index.html#FAQ-59
+ 98. http://www.karlrunge.com/x11vnc/index.html#solarisbuilding
+ 99. http://www.karlrunge.com/x11vnc/index.html#building
+ 100. http://www.karlrunge.com/x11vnc/index.html#buildfaq
+ 101. http://packages.debian.org/x11vnc
+ 102. http://www.linuxpackages.net/search_view.php?by=name&name=x11vnc
+ 103. http://dag.wieers.com/packages/x11vnc/
+ 104. http://www.bell-labs.com/project/wwexptools/packages.html
+ 105. http://www.karlrunge.com/x11vnc/index.html#solarisbuilding
+ 106. http://www.tightvnc.com/download.html
+ 107. http://www.realvnc.com/download-free.html
+ 108. http://sourceforge.net/projects/cotvnc/
+ 109. http://www.karlrunge.com/x11vnc/x11vnc_opts.html
+ 110. http://www.karlrunge.com/x11vnc/index.html#tunnelling
+ 111. http://www.karlrunge.com/x11vnc/index.html#passwd
+ 112. http://www.karlrunge.com/x11vnc/index.html#passwdfile
+ 113. http://fredrik.hubbe.net/x2vnc.html
+ 114. http://www.hubbe.net/~hubbe/win2vnc.html
+ 115. http://www.deboer.gmxhome.de/
+ 116. http://sourceforge.net/projects/win2vnc/
+ 117. http://fredrik.hubbe.net/x2vnc.html
+ 118. http://freshmeat.net/projects/x2x/
+ 119. http://ftp.digital.com/pub/Digital/SRC/x2x/
+ 120. http://zapek.com/software/zvnc/
+ 121. http://www.karlrunge.com/x11vnc/index.html#8bpp
+ 122. http://www.karlrunge.com/x11vnc/index.html#overlays
+ 123. http://www.karlrunge.com/x11vnc/index.html#inetd
+ 124. ftp://ftp.x.org/
+ 125. http://www.karlrunge.com/x11vnc/dtVncPopup
+ 126. http://www.karlrunge.com/x11vnc/index.html#passwdfile
127. http://www.karlrunge.com/x11vnc/index.html#tunnelling
128. http://www.karlrunge.com/x11vnc/index.html#tunnelling
- 129. http://www.karlrunge.com/x11vnc/blockdpy.c
- 130. http://www.karlrunge.com/x11vnc/x11vnc.c
- 131. http://www.karlrunge.com/x11vnc/x11vnc_loop
- 132. http://www.tightvnc.com/
- 133. http://www.karlrunge.com/x11vnc/shm_clear
- 134. http://www.karlrunge.com/x11vnc/index.html#noshm
- 135. http://www.tightvnc.com/
- 136. http://www.karlrunge.com/x11vnc/index.html#greaterless
- 137. http://www.karlrunge.com/x11vnc/index.html#xkbmodtweak
- 138. http://www.karlrunge.com/x11vnc/index.html#xkbmodtweak
- 139. http://www.karlrunge.com/x11vnc/index.html#scaling
- 140. http://www.karlrunge.com/x11vnc/index.html#solshm
+ 129. http://www.karlrunge.com/x11vnc/index.html#tunnelling
+ 130. http://www.karlrunge.com/x11vnc/index.html#tunnelling
+ 131. http://www.karlrunge.com/x11vnc/blockdpy.c
+ 132. http://www.karlrunge.com/x11vnc/x11vnc.c
+ 133. http://www.karlrunge.com/x11vnc/x11vnc_loop
+ 134. http://www.tightvnc.com/
+ 135. http://www.karlrunge.com/x11vnc/shm_clear
+ 136. http://www.karlrunge.com/x11vnc/index.html#noshm
+ 137. http://www.tightvnc.com/
+ 138. http://www.karlrunge.com/x11vnc/index.html#greaterless
+ 139. http://www.karlrunge.com/x11vnc/index.html#xkbmodtweak
+ 140. http://www.karlrunge.com/x11vnc/index.html#xkbmodtweak
+ 141. http://www.karlrunge.com/x11vnc/index.html#scaling
+ 142. http://www.karlrunge.com/x11vnc/index.html#solshm
=======================================================================
@@ -2608,7 +2702,7 @@ x11vnc: a VNC server for real X displays
% x11vnc -help
x11vnc: allow VNC connections to real X11 displays. 0.6.3pre lastmod: 2004-12-1
-6
+9
Typical usage is:
@@ -2699,7 +2793,7 @@ Options:
cursor shape is exactly correct in this mode.
Use -overlay as a workaround for situations like these:
- Some legacy applications require the default visual
+ 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 messed
@@ -3074,25 +3168,33 @@ Options:
initial state of the modifier is ignored and not reset)
To include button events use "Button1", ... etc.
--nodragging Do not update the display during mouse dragging events
- (mouse motion with a button held down). Greatly
- improves response on slow setups, but you lose all
- visual feedback for drags, text selection, and some
- menu traversals.
+-nodragging Do not update the display during mouse dragging
+ events (mouse motion with a 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 -pointer_mode setting
+ (think of it as pointer_mode 0)
-pointer_mode n Various pointer update schemes. The problem is pointer
motion can cause rapid changes on the screen, e.g. a
- window drag. Neither x11vnc nor the bandwidth to the
- vncviewers can keep up these rapid screen changes:
- everything bogs down when dragging or scrolling.
- Note that most video h/w is optimized for writing, not
- reading (a 50X rate difference is possible) and x11vnc
- is reading all the time. So a scheme has to be used to
- "eat" much of that pointer input before re-polling the
- screen. n can be 1 to 4. n=1 was the original scheme
- used to about Jan 2004. n=2 is an improved scheme.
- n=3 is basically a dynamic -nodragging mode: it detects
- if the mouse drag motion has paused and refreshes
- the display. n=4 is TBD. The default n is 2.
+ window drag. Neither x11vnc's screen polling nor the
+ bandwidth to the vncviewers can keep up these rapid
+ screen changes: everything bogs down when dragging
+ or scrolling. Note that most video h/w is optimized
+ for writing, not reading (a 50X rate difference is
+ possible) and x11vnc is reading all the time. So a
+ scheme has to be used to "eat" much of that pointer
+ input before re-polling the screen. n can be 1 to 4.
+
+ n=1 was the original scheme used to about Jan 2004: it
+ basically just skips -input_skip pointer events before
+ repolling the screen. n=2 is an improved scheme:
+ by watching the current rate it tries to detect if
+ it should try to "eat" more pointer events. n=3 is
+ basically a dynamic -nodragging mode: it detects if the
+ mouse drag motion has paused and refreshes the display.
+ n=4 is TBD, it will try measure screen read and client
+ write rates and try to insert "frames" between the
+ on/off states of mode 3. The default n is 2.
-input_skip n 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.
@@ -3133,9 +3235,10 @@ Options:
-gui [gui-opts] Start up a simple tcl/tk gui based on the the remote
control options -remote/-query described below.
- "gui-opts" is not required: the default is to start
- up both the gui and x11vnc with the gui showing up on
- the X display in the environment variable DISPLAY.
+ Requires the "wish" program to be installed on the
+ machine. "gui-opts" is not required: the default is
+ to start up both the gui and x11vnc with the gui showing
+ up on the X display in the environment variable DISPLAY.
"gui-opts" can be a comma separated list of items.
Currently there are only two types of items: 1) a gui
@@ -3146,14 +3249,14 @@ Options:
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 one.)
+ or connect to an existing one.)
Note the possible confusion regarding the potentially
- two 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).
+ 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).
Examples: "x11vnc -gui", "x11vnc -gui localhost:10",
"x11vnc -gui :10", "x11vnc -gui wait,:10",
@@ -3211,8 +3314,9 @@ Options:
could miss it). Same as "zero", also
"zero:x1,y1,x2,y2" for a rectangle.
refresh send the entire fb to all clients.
- reset recreate the fb, polling mem, etc.
- id:windowid set -id window to "windowid"
+ reset recreate the fb, polling memory, etc.
+ id:windowid set -id window to "windowid". empty
+ or "root" to go back to root window
sid:windowid set -sid window to "windowid"
flashcmap enable -flashcmap mode.
noflashcmap disable -flashcmap mode.
@@ -3313,7 +3417,7 @@ Options:
nocursorpos enable -nocursorpos mode.
xwarp enable -xwarppointer mode.
noxwarp disable -xwarppointer mode.
- buttonmap:str set -buttonmap "str" empty to disable
+ buttonmap:str set -buttonmap "str", empty to disable
dragging disable -nodragging mode.
nodragging enable -nodragging mode.
pointer_mode n set -pointer_mode to n.
@@ -3407,6 +3511,25 @@ Options:
dpy_x dpy_y rfbport rfbwait rfbauth passwd alwaysshared
dontdisconnect httpdir enablehttpproxy
+-sync By default -remote commands are run asynchronously, that
+ is, the request is posted and the program immediately
+ exits. Use -sync to have the program wait for an
+ acknowledgement from the x11vnc server that command
+ was processed. On the other hand -query requests are
+ always processed synchronously because they have wait
+ for the result.
+
+ Also note that if both -remote and -query requests are
+ supplied on the command line, the -remote is processed
+ first (synchronously: no need for -sync), and then
+ the -query request is processed in the normal way.
+ This allows for a reliable way to see if the -remote
+ 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.
+
-noremote Do not process any remote control commands or queries.
A note about security wrt remote control commands.