vncviewer(1) Virtual Network Computing vncviewer(1)NAMEvncviewer - VNC viewer for X
SYNOPSISvncviewer [options] [host][:display#]
vncviewer [options] [host][::port]
vncviewer [options] -listen [port]
DESCRIPTIONvncviewer is a viewer (client) for Virtual Network Computing. This
manual page documents version 4 for the X window system.
If you run the viewer with no arguments it will prompt you for a VNC
server to connect to. Alternatively, specify the VNC server as an
argument, e.g.:
vncviewer snoopy:2
where 'snoopy' is the name of the machine, and '2' is the display num‐
ber of the VNC server on that machine. Either the machine name or dis‐
play number can be omitted. So for example ":1" means display number 1
on the same machine, and "snoopy" means "snoopy:0" i.e. display 0 on
machine "snoopy".
If the VNC server is successfully contacted, you will be prompted for a
password to authenticate you. If the password is correct, a window
will appear showing the desktop of the VNC server.
AUTOMATIC PROTOCOL SELECTION
The viewer tests the speed of the connection to the server and chooses
the encoding and pixel format (color level) appropriately. This makes
it much easier to use than previous versions where the user had to
specify arcane command line arguments.
The viewer normally starts out assuming the link is slow, using the
encoding with the best compression. If it turns out that the link is
fast enough it switches to an encoding which compresses less but is
faster to generate, thus improving the interactive feel.
The viewer normally starts in full-color mode, but switches to low-
color mode if the bandwidth is insufficient. However, this only occurs
when communicating with servers supporting protocol 3.8 or newer, since
many old servers does not support color mode changes safely.
Automatic selection can be turned off by setting the AutoSelect parame‐
ter to false, or from the options dialog.
POPUP MENU
The viewer has a popup menu containing entries which perform various
actions. It is usually brought up by pressing F8, but this can be con‐
figured with the MenuKey parameter. Actions which the popup menu can
perform include:
* switching in and out of full-screen mode
* quitting the viewer
* generating key events, e.g. sending ctrl-alt-del
* accessing the options dialog and various other dialogs
By default, key presses in the popup menu get sent to the VNC server
and dismiss the popup. So to get an F8 through to the VNC server sim‐
ply press it twice.
FULL SCREEN MODE
A full-screen mode is supported. This is particularly useful when con‐
necting to a remote screen which is the same size as your local one. If
the remote screen is bigger, you can scroll by bumping the mouse
against the edge of the screen.
Unfortunately this mode doesn't work completely with all window man‐
agers, since it breaks the X window management conventions.
OPTIONS (PARAMETERS)
You can get a list of parameters by giving -h as a command-line option
to vncviewer. Parameters can be turned on with -param or off with
-param=0. Parameters which take a value can be specified as -param
value. Other valid forms are param=value -param=value --param=value.
Parameter names are case-insensitive.
Many of the parameters can also be set graphically via the options dia‐
log box. This can be accessed from the popup menu or from the "Connec‐
tion details" dialog box.
-display Xdisplay
Specifies the X display on which the VNC viewer window should
appear.
-geometry geometry
Standard X position and sizing specification.
-listen [port]
Causes vncviewer to listen on the given port (default 5500) for
reverse connections from a VNC server. WinVNC supports reverse
connections initiated using the 'Add New Client' menu option or
the '-connect' command-line option. Xvnc supports reverse con‐
nections with a helper program called vncconfig.
-passwd password-file
If you are on a filesystem which gives you access to the pass‐
word file used by the server, you can specify it here to avoid
typing it in. It will usually be "~/.vnc/passwd".
-Shared
When you make a connection to a VNC server, all other existing
connections are normally closed. This option requests that they
be left open, allowing you to share the desktop with someone
already using it.
-ViewOnly
Specifies that no keyboard or mouse events should be sent to the
server. Useful if you want to view a desktop without interfer‐
ing; often needs to be combined with -Shared.
-FullScreen
Start in full-screen mode.
-DesktopSize widthxheight
Instead of keeping the existing remote screen size, the client
will attempt to switch to the specified since when connecting.
If the server does not support the SetDesktopSize message then
the screen will retain the original size.
-AutoSelect
Use automatic selection of encoding and pixel format (default is
on). Normally the viewer tests the speed of the connection to
the server and chooses the encoding and pixel format appropri‐
ately. Turn it off with -AutoSelect=0.
-FullColor, -FullColour
Tells the VNC server to send full-color pixels in the best for‐
mat for this display. This is default.
-LowColorLevel, -LowColourLevel level
Selects the reduced color level to use on slow links. level can
range from 0 to 2, 0 meaning 8 colors, 1 meaning 64 colors (the
default), 2 meaning 256 colors. Note that decision if reduced
color level is used is made by vncviewer. If you would like to
force vncviewer to use reduced color level use -AutoSelect=0
parameter.
-PreferredEncoding encoding
This option specifies the preferred encoding to use from one of
"Tight", "ZRLE", "hextile" or "raw".
-UseLocalCursor
Render the mouse cursor locally if the server supports it
(default is on). This can make the interactive performance feel
much better over slow links.
-WMDecorationWidth w, -WMDecorationHeight h
The total width and height taken up by window manager decora‐
tions. This is used to calculate the maximum size of the VNC
viewer window. Default is width 6, height 24.
-log logname:dest:level
Configures the debug log settings. dest can currently be stderr
or stdout, and level is between 0 and 100, 100 meaning most ver‐
bose output. logname is usually * meaning all, but you can tar‐
get a specific source file if you know the name of its "Log‐
Writer". Default is *:stderr:30.
-MenuKey keysym-name
This option specifies the key which brings up the popup menu.
The key is specified as an X11 keysym name (these can be
obtained by removing the XK_ prefix from the entries in
"/usr/include/X11/keysymdef.h"). Default is F8.
-via gateway
Automatically create encrypted TCP tunnel to the gateway machine
before connection, connect to the host through that tunnel
(TigerVNC-specific). By default, this option invokes SSH local
port forwarding, assuming that SSH client binary can be accessed
as /usr/bin/ssh. Note that when using the -via option, the host
machine name should be specified as known to the gateway
machine, e.g. "localhost" denotes the gateway, not the machine
where vncviewer was launched. The environment variable
VNC_VIA_CMD can override the default tunnel command of
/usr/bin/ssh -f -L "$L":"$H":"$R" "$G" sleep 20. The tunnel
command is executed with the environment variables L, H, R, and
G taken the values of the local port number, the remote host,
the port number on the remote host, and the gateway machine
respectively.
SEE ALSOXvnc(1), vncpasswd(1), vncconfig(1), vncserver(1)
http://www.tigervnc.org
AUTHOR
Tristan Richardson, RealVNC Ltd.
VNC was originally developed by the RealVNC team while at Olivetti
Research Ltd / AT&T Laboratories Cambridge. TightVNC additions were
implemented by Constantin Kaplinsky. Many other people participated in
development, testing and support.
TigerVNC 05 May 2004 vncviewer(1)
