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Xvnc(1)				   TightVNC			       Xvnc(1)

       Xvnc - an X server providing VNC	connectivity

       Xvnc   [:display] [-geometry widthxheight] [-depth depth] [-pixelformat
	      rgbNNN|bgrNNN] [-udpinputport port]  [-rfbport  port]  [-rfbwait
	      time] [-nocursor]	[-rfbauth passwd-file] [-httpd dir] [-httpport
	      port]  [-deferupdate  time]  [-economictranslate]	  [-lazytight]
	      [-desktop	name] [-alwaysshared] [-nevershared] [-dontdisconnect]
	      [-viewonly] [-localhost] [-interface ipaddr] [-inetd] [-compati-
	      blekbd] [X-options...]

       Xvnc  is	 a  VNC	 (Virtual Network Computing) server. It	acts like an X
       server with a virtual display. The display can be seen by a VNC	viewer
       application,   which  may  be  running  on  a  different	 machine:  see
       vncviewer(1). Xvnc is built inside the source code tree of XFree86, and
       shares many options with	it.

       Normally,  you  don't need to start Xvnc	manually; use the vncserver(1)
       wrapper script instead. This script sets	reasonable defaults  for  Xvnc
       session,	checks many error conditions etc.

       Please  read  the  BUGS	section	if you plan to use VNC on an untrusted

       Xvnc supports many standard X server options and	a number  of  VNC-spe-
       cific  options.	To  see	 what standard X server	options	are supported,
       please look at the Xvnc -help output and	 read  the  Xserver(1)	manual
       page for	details	on those options.

       The VNC-specific	options	are as follows:

       -geometry widthxheight
	      Set desktop width	and height.

       -depth depth
	      Set  the	colour	depth  of  the	visual to provide, in bits per
	      pixel. Must be a value between 8 and 32.

       -pixelformat rgbNNN|bgrNNN
	      Set colour format	for pixels representation. The viewer  can  do
	      the  conversion  to  any other pixel format, but it is faster if
	      the depth	and pixel format of the	server	is  the	 same  as  the
	      equivalent values	on the viewer display.

       -udpinputport port
	      UDP port for keyboard/pointer data.

       -rfbport	port
	      TCP  port	 for  RFB protocol. The	RFB protocol is	used for comm-
	      nunication between VNC server and	clients.

       -rfbwait	time
	      Maximum time, in milliseconds, to	wait for an  RFB  client  (VNC

	      Don't put	up a pointer cursor on the desktop.

       -rfbauth	passwd-file
	      Use  authentication on RFB protocol from the specified file. The
	      passwd-file can be created using the vncpasswd(1)	utility.

       -httpd dir
	      Serve files via HTTP protocol from the specified directory. Nor-
	      mally, Java viewer classes are stored in such directory.

       -httpport port
	      TCP  port	 on which Xvnc should listen for incoming HTTP connec-
	      tions (to	allow access to	 the  desktop  from  any  Java-capable

       -deferupdate time
	      Time  in milliseconds, to	defer screen updates (default 40). De-
	      ferring updates helps to coalesce	 many  small  desktop  changes
	      into a few larger	updates	thus saving network bandwidth.

	      Use less memory-hungry pixel format translation.

	      Disable  the  "gradient" filter in Tight encoding	(TightVNC-spe-
	      cific).  The "gradient" filter often helps to improve data  com-
	      pression	ratios,	 but  may  slow	 down  the server performance.
	      Please note that this filter is never used when a	client enables
	      JPEG compression in the Tight encoding.

       -desktop	name
	      Set VNC desktop name ("x11" by default).

	      Always  treat  new  clients as shared, never disconnect existing
	      client on	a new client connection.

	      Never treat new clients as shared, do not	allow several simulta-
	      neous client connections.

	      Don't  disconnect	existing clients when a	new non-shared connec-
	      tion comes in, refuse new	connection instead.

	      Don't accept  keboard  and  pointer  events  from	 clients.  All
	      clients  will  be	 able  to see the desktop but won't be able to
	      control it.

	      Only allow loopback connections from localhost. This  option  is
	      useful in	conjunction with SSH tunneling.

       -interface ipaddr
	      Listen for client	connections only on the	network	interface with
	      given ipaddr.

       -inetd Xvnc is launched by inetd. This option causes Xvnc  to  redirect
	      network input/output to stdin/stdout.

	      Set  META	 and  ALT  keys	to the same X modifier flag, as	in the
	      original version of Xvnc by AT&T labs (TightVNC-specific).

       There are many security problems	in current Xvnc	 implementation.  It's
       recommended  to	restrict network access	to Xvnc	servers	from untrusted
       network adresses. Probably, the best way	to secure Xvnc	server	is  to
       allow only loopback connections from the	server machine (the -localhost
       option) and to use SSH tunneling	for remote access to the Xvnc  server.
       For    details	 on    SSH   tunneling,	  see	<URL:> .

       vncserver(1), vncviewer(1), vncpasswd(1), vncconnect(1),	sshd(1)

       Original	VNC was	developed in AT&T Laboratories Cambridge. TightVNC ad-
       ditions	were  implemented  by  Constantin Kaplinsky. Many other	people
       participated in development, testing and	support.

       Man page	authors:
       Marcus Brinkmann	<>,
       Tim Waugh <>,
       Constantin Kaplinsky <>

				  August 2006			       Xvnc(1)


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