x0vncserver - TigerVNC Server for X displays
/usr/bin/x0vncserver [options] x0vncserver -version
X0VNCSERVER(1) TigerVNC Manual X0VNCSERVER(1)
NAME
x0vncserver - TigerVNC Server for X displays
SYNOPSIS
/usr/bin/x0vncserver [options]
x0vncserver -version
DESCRIPTION
x0vncserver is a TigerVNC Server which makes any X display remotely
accessible via VNC, TigerVNC or compatible viewers. Unlike Xvnc(1), it
does not create a virtual display. Instead, it just shares an existing
X server (typically, that one connected to the physical screen).
OPTIONS
x0vncserver interprets the command line as a list of parameters with
optional values. Running x0vncserver -h will show a list of all valid
parameters with short descriptions. All parameters are optional, but
normally you would have to use the PasswordFile parameter (see its
description below).
There are several forms of specifying parameters in the command line
(here we use `SomeParameter' as an example parameter name):
-SomeParameter
Enable the parameter, turn the feature on. This form can be
used with parameters that simply enable or disable some feature.
-SomeParameter=0
Disable the parameter, turn the feature off.
-SomeParameter=value
Assign the specified value to the parameter. The leading dash
can be omitted, or it can be doubled if desired (like in GNU-
style long options).
Parameter names are case-insensitive, their order in the command line
can be arbitrary.
PARAMETERS
display
The X display name. If not specified, it defaults to the value
of the DISPLAY environment variable.
rfbport
TCP port to listen for incoming VNC connections (RFB protocol).
The default port is 5900.
Log Specifies which log output should be directed to which target
logger, and the level of output to log. Format is log:tar-
get:level. Default is *:stderr:30 (log everything to stderr,
set log level to 30). Log level should be a value between 0 and
100, higher levels produce more output.
HostsFile
This parameter allows to specify a file name with IP access con-
trol rules. The file should include one rule per line, and the
rule format is one of the following: +address/netmask (accept
connections from the specified address group), -address/netmask
(reject connections) or ?address/netmask (query the local user).
The first rule matching the IP address determines the action to
be performed. Rules that include only an action sign (+, - or
?) will match any IP address. Netmask is optional and can be
specified either in dotted format (e.g. /255.255.255.0), or as a
single number of bits (e.g. /24). Default is to accept connec-
tions from any IP address.
SecurityTypes
Specify which security scheme to use for incoming connections.
Valid values are None and VncAuth. Default is VncAuth.
PasswordFile
Password file for VNC authentication. There is no default, you
should specify the password file explicitly. Password file
should be created with the vncpasswd(1) utility.
Password
Obfuscated binary encoding of the password which clients must
supply to access the server. Using this parameter is insecure,
use PasswordFile parameter instead.
BlacklistThreshold
The number of unauthenticated connection attempts allowed from
any individual host before that host is black-listed. Default
is 5.
BlacklistTimeout
The initial timeout applied when a host is first black-listed.
The host cannot re-attempt a connection until the timeout
expires. Default is 10.
QueryConnect
Prompt the local user to accept or reject incoming connections.
Default is off.
QueryConnectTimeout
Number of seconds to show the Accept Connection dialog before
rejecting the connection. Default is 10.
AlwaysShared
Always treat incoming connections as shared, regardless of the
client-specified setting. Default is off.
NeverShared
Never treat incoming connections as shared, regardless of the
client-specified setting. Default is off.
DisconnectClients
Disconnect existing clients if an incoming connection is non-
shared. If combined with NeverShared then new connections will
be refused while there is a client active. Default is on.
AcceptKeyEvents
Accept key press and release events from clients. Default is
on.
AcceptPointerEvents
Accept pointer events from clients. Default is on.
RemapKeys
Comma-separated list of incoming keysyms to remap. Mappings are
expressed as two hex values, prefixed by 0x, and separated by ->
(`dash' and `greater than' characters).
Protocol3.3
Always use RFB protocol version 3.3 for backwards compatibility
with badly-behaved clients. Default is off.
Geometry
This option specifies the screen area that will be shown to VNC
clients. The format is widthxheight+xoffset+yoffset , where `+'
signs can be replaced with `-' signs to specify offsets from the
right and/or from the bottom of the screen. Offsets are
optional, +0+0 is assumed by default (top left corner). If the
argument is empty, full screen is shown to VNC clients (this is
the default).
MaxProcessorUsage
Maximum percentage of CPU time to be consumed when polling the
screen. Default is 35.
PollingCycle
Milliseconds per one polling cycle. Actual interval may be
dynamically adjusted to satisfy MaxProcessorUsage setting.
Default is 30.
VideoArea
This option specifies the screen area that will be handled as
video. The format is widthxheight+xoffset+yoffset , where `+'
signs can be replaced with `-' signs to specify offsets from the
right and/or from the bottom of the screen. Offsets are
optional, +0+0 is assumed by default (top left corner). Video
area is not checked for actual changes, it is assumed to be
changing continuously and is sent in each screen update. Nor-
mally, video area is compressed with JPEG (if allowed by the
client). Note that this setting can be overriden by TigerVNC
clients supporting VideoRectangleSelection protocol extension.
In other words, clients may choose video selection themselves,
but if they do not, then the VideoArea parameter will take
effect. If the argument is empty, no video area is set (this is
the default).
VideoPriority
Specify the priority of sending video updates. x0vncserver can
be instructed to treat certain rectangular part of the screen as
a video area and handle it in a special way for improved perfor-
mance (see documentation on the VideoArea parameter). VideoPri-
ority value controls how often video area will be sent to
clients as compared to the rest of the screen. The priority
must be an integer between 0 and 8, and the default value is 2.
VideoPriority set to 1 gives the same priority both to video and
to other pixels. Higher values give more priority to video.
For example, the value 5 specifies that the rate of sending
video will be five times higher than the rate of updating the
rest of the screen. If VideoPriority is set to 0, it gives
equal priority to video and other updates (just like the value
1) and also disables special encoding for video data. In other
words, VideoPriority video area will be sent as a part of other
screen contents.
CompareFB
Perform pixel comparison on framebuffer to reduce unnecessary
updates. Default is on.
UseSHM Use MIT-SHM extension if available. Using that extension accel-
erates reading the screen. Default is on.
OverlayMode
Use overlay mode in IRIX or Solaris (does not have effect in
other systems). This enables system-specific access to complete
full-color version of the screen (the default X visual often
provides 256 colors). Also, in overlay mode, x0vncserver can
show correct mouse cursor. Default is on.
UseHardwareJPEG
Use hardware-accelerated JPEG compressor for video if available.
x0vncserver can be instructed to treat certain rectangular part
of the screen as a video area and handle it in a special way for
improved performance. If the client supports Tight encoding and
JPEG compression, such video areas will be sent as JPEG-encoded
rectangles. And if this option is on, compression will be hard-
ware-accelerated (currently, supported only in SGI/IRIX equipped
with appropriate hardware). Default is on.
ZlibLevel
Zlib compression level for ZRLE encoding (it does not affect
Tight encoding). Acceptable values are between 0 and 9.
Default is to use the standard compression level provided by the
zlib(3) compression library.
ImprovedHextile
Use improved compression algorithm for Hextile encoding which
achieves better compression ratios by the cost of using slightly
more CPU time. Default is on.
IdleTimeout
The number of seconds after which an idle VNC connection will be
dropped (zero means no timeout). Default is 0.
MaxDisconnectionTime
Terminate when no client has been connected for N seconds.
Default is 0.
MaxConnectionTime
Terminate when a client has been connected for N seconds.
Default is 0.
MaxIdleTime
Terminate after N seconds of user inactivity. Default is 0.
ClientWaitTimeMillis
The number of milliseconds to wait for a client which is no
longer responding. Default is 20000.
SEE ALSO
Xvnc(1), vncpasswd(1),
http://www.tigervnc.org/
AUTHOR
This manual page was written by Constantin Kaplinsky.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |x11/server/xvnc |
+-----------------------------+-----------------------------+
|Interface Stability |Volatile |
+-----------------------------+-----------------------------+
TigerVNC Dec 23, 2008 X0VNCSERVER(1)