Xvnc(1) 							     TightVNC								   Xvnc(1)

NAME

       Xvnc - an X server providing VNC connectivity

SYNOPSIS

       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] [-compatiblekbd] [X-
	      options...]

DESCRIPTION

       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 network.

OPTIONS

       Xvnc  supports  many  standard  X server options and a number of VNC-specific 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 commnunication between VNC server and clients.

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

       -nocursor
	      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. Normally, Java viewer classes are stored in such directory.

       -httpport port
	      TCP port on which Xvnc should listen for incoming HTTP connections (to allow access to the desktop from any Java-capable browser).

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

       -economictranslate
	      Use less memory-hungry pixel format translation.

       -lazytight
	      Disable the "gradient" filter in Tight encoding (TightVNC-specific).  The "gradient" filter often helps to improve data  compression
	      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).

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

       -nevershared
	      Never treat new clients as shared, do not allow several simultaneous client connections.

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

       -viewonly
	      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.

       -localhost
	      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.

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

BUGS

       There are many security problems in current Xvnc implementation. It's recommended to restrict network access to Xvnc servers from untrusted
       network	addresses. Probably, the best way to secure Xvnc server is to allow only loopback connections from the server machine (the -local-
       host  option)  and  to  use  SSH  tunneling  for  remote   access   to	the   Xvnc   server.   For   details   on   SSH   tunneling,   see
       <URL:http://www.cl.cam.ac.uk/Research/DTG/attarchive/vnc/sshvnc.html> .

SEE ALSO

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

AUTHORS

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

       Man page authors:
       Marcus Brinkmann <Marcus.Brinkmann@ruhr-uni-bochum.de>,
       Tim Waugh <twaugh@redhat.com>,
       Constantin Kaplinsky <const@tightvnc.com>

								    August 2006 							   Xvnc(1)