Provided by: ssvnc_1.0.29-2+deb8u1build0.16.04.1_amd64 bug

NAME

       ssvncviewer - an X viewer client for VNC

SYNOPSIS

       ssvncviewer [options] [host][:display]
       ssvncviewer [options] [host][::port]
       ssvncviewer [options] exec=[cmd+args...]
       ssvncviewer [options] fd=n
       ssvncviewer [options] /path/to/unix/socket
       ssvncviewer [options] unix=/path/to/unix/socket
       ssvncviewer [options] -listen [display]
       ssvncviewer -help

DESCRIPTION

       ssvncviewer  is  an  Xt-based  client  application for the VNC (Virtual Network Computing)
       system. It can connect to any VNC-compatible server  such  as  Xvnc,  WinVNC,  or  x11vnc,
       allowing you to control desktop environment of a different machine.

       ssvncviewer  is an enhanced version of the tightvnc unix viewer that can take advantage of
       features in the x11vnc and UltraVNC VNC servers.  See below for the description  of  these
       features.

       You  can  use  F8 to display a pop-up utility menu (also F7 on MacOSX.)  Press F8 twice to
       pass single F8 to the remote side.

OPTIONS

       -help  Prints a short usage notice to stderr.

       -listen
              Make the viewer listen on port 5500+display for reverse connections from a  server.
              WinVNC  supports reverse connections using the "Add New Client" menu option, or the
              -connect command  line  option.  Xvnc  requires  the  use  of  the  helper  program
              vncconnect.

       -via gateway
              Automatically create encrypted TCP tunnel to the gateway machine before connection,
              connect to the host through  that  tunnel  (TightVNC-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.  See  the  ENVIRONMENT
              section below for the information on configuring the -via option.

       -shared
              When  connecting,  specify that a shared connection is requested. In TightVNC, this
              is the default mode, allowing you to share the desktop with other  clients  already
              using it.

       -noshared
              When  connecting,  specify  that  the  session may not be shared. This would either
              disconnect other connected clients or refuse  your  connection,  depending  on  the
              server configuration.

       -viewonly
              Disable transfer of mouse and keyboard events from the client to the server.

       -fullscreen
              Start  in  full-screen mode. Please be aware that operating in full-screen mode may
              confuse X window managers. Typically, such conflicts cause  incorrect  handling  of
              input  focus or make the viewer window disappear mysteriously. See the grabKeyboard
              setting in the RESOURCES section below for a method to solve input focus problem.

       -noraiseonbeep
              By default, the viewer shows and raises its window on  remote  beep  (bell)  event.
              This option disables such behaviour (TightVNC-specific).

       -user username
              User  name for Unix login authentication. Default is to use current Unix user name.
              If this option was given, the viewer will prefer Unix login authentication over the
              standard VNC authentication.

       -passwd passwd-file
              File  from  which  to  get the password (as generated by the vncpasswd(1) program).
              This option affects only the standard VNC authentication.

       -encodings encoding-list
              TightVNC supports several different compression methods to encode  screen  updates;
              this  option  specifies  a set of them to use in order of preference. Encodings are
              specified separated with spaces, and must thus be enclosed in quotes if  more  than
              one  is  specified.   Commas  may be used to avoid spaces.  Available encodings, in
              default order for a remote connection, are "copyrect tight hextile zlib  corre  rre
              raw".  For  a  local  connection (to the same machine), the default order to try is
              "raw copyrect tight hextile zlib corre rre". Raw encoding is always  assumed  as  a
              last  option if no other encoding can be used for some reason. For more information
              on encodings, see the section ENCODINGS below.

       -bgr233
              Always use the BGR233 format to encode pixel data. This  reduces  network  traffic,
              but  colors  may  be  represented inaccurately. The bgr233 format is an 8-bit "true
              color" format, with 2 bits blue, 3 bits green, and 3 bits red.

       -owncmap
              Try to use a PseudoColor visual and a private colormap. This allows the VNC  server
              to control the colormap.

       -truecolour, -truecolor
              Try to use a TrueColor visual.

       -depth depth
              On  an  X  server  which  supports  multiple TrueColor visuals of different depths,
              attempt to use the specified one (in bits per pixel);  if  successful,  this  depth
              will be requested from the VNC server.

       -compresslevel level
              Use   specified   compression   level  (0..9)  for  "tight"  and  "zlib"  encodings
              (TightVNC-specific). Level 1 uses minimum of CPU time and achieves weak compression
              ratios,  while  level  9  offers  best compression but is slow in terms of CPU time
              consumption on the server side. Use high levels with very slow network connections,
              and  low  levels  when  working  over  high-speed LANs. It's not recommended to use
              compression level 0, reasonable choices start from the level 1.

       -quality level
              Use  the  specified  JPEG  quality  level   (0..9)   for   the   "tight"   encoding
              (TightVNC-specific).  Quality level 0 denotes bad image quality but very impressive
              compression ratios,  while  level  9  offers  very  good  image  quality  at  lower
              compression  ratios.  Note  that the "tight" encoder uses JPEG to encode only those
              screen areas that look suitable for lossy compression, so quality level 0 does  not
              always mean unacceptable image quality.

       -nojpeg
              Disable  lossy  JPEG  compression in Tight encoding (TightVNC-specific).  Disabling
              JPEG compression is not a good idea in typical  cases,  as  that  makes  the  Tight
              encoder  less  efficient.  You  might  want  to  use this option if it's absolutely
              necessary to achieve perfect image quality (see also the -quality option).

       -nocursorshape
              Disable cursor shape updates, protocol extensions  used  to  handle  remote  cursor
              movements  locally  on  the  client  side  (TightVNC-specific).  Using cursor shape
              updates decreases delays with remote cursor movements, and  can  improve  bandwidth
              usage dramatically.

       -x11cursor
              Use  a  real  X11  cursor with X-style cursor shape updates, instead of drawing the
              remote cursor on the framebuffer. This option also disables  the  dot  cursor,  and
              disables cursor position updates in non-fullscreen mode.

       -autopass
              Read  a  plain-text  password from stdin. This option affects only the standard VNC
              authentication.

Enhanced TightVNC Viewer (SSVNC) OPTIONS

       Enhanced TightVNC Viewer (SSVNC) web page is located at:

       http://www.karlrunge.com/x11vnc/ssvnc.html

       Note: ZRLE and ZYWRLE encodings are now supported.

       Note: F9 is shortcut to Toggle FullScreen mode.

       Note: In -listen mode set the env var. SSVNC_MULTIPLE_LISTEN=1
              to allow more than one incoming VNC  server  at  a  time.   This  is  the  same  as
              -multilisten  described  below.   Set  SSVNC_MULTIPLE_LISTEN=MAX:n to allow no more
              than "n" simultaneous reverse connections.

              If the host:port is specified as "exec=command args..."  then instead of  making  a
              TCP/IP  socket  connection  to the remote VNC server, "command args..." is executed
              and the viewer is attached to its stdio.  This enables tunnelling  established  via
              an  external  command, e.g. an stunnel(8) that does not involve a listening socket.
              This mode does not work for -listen reverse connections.  To not have the exec= pid
              killed at exit, set SSVNC_NO_KILL_EXEC_CMD=1.

              If  the  host:port is specified as "fd=n" then it is assumed n is an already opened
              file descriptor to the socket. (i.e the parent did fork+exec)

              If the host:port contains a '/' and exists in the file system it is interpreted  as
              a  unix-domain  socket  (AF_LOCAL/AF_UNIX instead of AF_INET)  Prefix with unix= to
              force interpretation as a unix-domain socket.

       -multilisten
              As in -listen (reverse connection listening) except allow more  than  one  incoming
              VNC  server  to  be  connected at a time.  The default for -listen of only one at a
              time tries to play it safe by not allowing anyone on  the  network  to  put  (many)
              desktops on your screen over a long window of time. Use -multilisten for no limit.

       -acceptpopup
              In  -listen (reverse connection listening) mode when a reverse VNC connection comes
              in show a popup asking whether to Accept or Reject the connection.  The IP  address
              of   the   connecting   host   is   shown.    Same   as   setting   the  env.  var.
              SSVNC_ACCEPT_POPUP=1.

       -acceptpopupsc
              As in -acceptpopup except assume UltraVNC Single Click (SC) server.  Retrieve  User
              and ComputerName info from UltraVNC Server and display in the Popup.

       -use64 In -bgr233 mode, use 64 colors instead of 256.

       -bgr222
              Same as -use64.

       -use8  In -bgr233 mode, use 8 colors instead of 256.

       -bgr111
              Same as -use8.

       -16bpp If  the  vnc  viewer X display is depth 24 at 32bpp request a 16bpp format from the
              VNC server to cut network traffic by up to 2X, then tranlate the  pixels  to  32bpp
              locally.

       -bgr565
              Same as -16bpp.

       -grey  Use a grey scale for the 16- and 8-bpp modes.

       -alpha Use  alphablending  transparency  for  local  cursors requires: x11vnc server, both
              client and server must be 32bpp and same endianness.

       -scale str
              Scale the desktop locally.  The string "str"  can  a  floating  point  ratio,  e.g.
              "0.9",  or a fraction, e.g. "3/4", or WxH, e.g. 1280x1024.  Use "fit" to fit in the
              current screen size.  Use "auto" to fit in the window size.  "str" can also be  set
              by the env. var. SSVNC_SCALE.

              If  you  observe  mouse  trail  painting errors, enable X11 Cursor mode (either via
              Popup or -x11cursor.)

              Note that scaling is done in software and so can be slow and requires more  memory.
              Some speedup Tips:

              ZRLE  is  faster  than  Tight  in  this  mode.  When scaling is first detected, the
              encoding will be automatically switched to ZRLE.  Use the Popup menu if you want to
              go back to Tight.  Set SSVNC_PRESERVE_ENCODING=1 to disable this.

              Use  a  solid  background  on the remote side.  (e.g. manually or via x11vnc -solid
              ...)

              If the remote server is x11vnc, try client side caching: x11vnc -ncache 10 ...

       -ycrop n
              Only show the top n rows of the framebuffer.  For use with  x11vnc  -ncache  client
              caching  option  to help "hide" the pixel cache region.  Use a negative value (e.g.
              -1) for autodetection.  Autodetection will always  take  place  if  the  remote  fb
              height is more than 2 times the width.

       -sbwidth n
              Scrollbar width for x11vnc -ncache mode (-ycrop), default is very narrow: 2 pixels,
              it is narrow to avoid distraction in -ycrop mode.

       -nobell
              Disable bell.

       -rawlocal
              Prefer raw encoding for localhost, default is no,  i.e.  assumes  you  have  a  SSH
              tunnel instead.

       -notty Try to avoid using the terminal for interactive responses: use windows for messages
              and prompting instead.  Messages will also be printed to terminal.

       -sendclipboard
              Send the X CLIPBOARD selection (i.e. Ctrl+C,  Ctrl+V)  instead  of  the  X  PRIMARY
              selection (mouse select and middle button paste.)

       -sendalways
              Whenever the mouse enters the VNC viewer main window, send the selection to the VNC
              server even if it has not changed.   This  is  like  the  Xt  resource  translation
              SelectionToVNC(always)

       -recvtext
              str    When cut text is received from the VNC server, ssvncviewer will set both the
              X PRIMARY and the X CLIPBOARD local selections.  To control which is  set,  specify
              'str' as 'primary', 'clipboard', or 'both' (the default.)

       -graball
              Grab  the  entire  X  server  when  in  fullscreen  mode, needed by some old window
              managers like fvwm2.

       -popupfix
              Warp the popup back to the pointer position, needed by  some  old  window  managers
              like fvwm2.

       -grabkbd
              Grab  the  X keyboard when in fullscreen mode, needed by some window managers. Same
              as -grabkeyboard.  -grabkbd is the default, use -nograbkbd to disable.

       -bs, -nobs
              Whether or not to use X server  Backingstore  for  the  main  viewer  window.   The
              default  is to not, mainly because most Linux, etc, systems X servers disable *all*
              Backingstore by default.  To re-enable it put

              Option "Backingstore"

              in the Device section  of  /etc/X11/xorg.conf.   In  -bs  mode  with  no  X  server
              backingstore,  whenever  an  area of the screen is re-exposed it must go out to the
              VNC server to retrieve the pixels. This is too slow.

              In -nobs mode, memory is allocated by the viewer to provide its own backing of  the
              main  viewer  window.  This actually makes some activities faster (changes in large
              regions) but can appear to "flash" too much.

       -noshm Disable use of MIT shared memory extension (not recommended)

       -termchat
              Do the UltraVNC chat in the terminal vncviewer is in instead of in  an  independent
              window.

       -unixpw str
              Useful  for logging into x11vnc in -unixpw mode. "str" is a string that allows many
              ways to enter the Unix Username and Unix  Password.   These  characters:  username,
              newline,  password, newline are sent to the VNC server after any VNC authentication
              has taken place.  Under x11vnc they are used for  the  -unixpw  login.   Other  VNC
              servers could do something similar.

              You can also indicate "str" via the environment variable SSVNC_UNIXPW.

              Note that the Escape key is actually sent first to tell x11vnc to not echo the Unix
              Username back to the VNC viewer. Set SSVNC_UNIXPW_NOESC=1 to override this.

              If str is ".", then you are prompted at the  command  line  for  the  username  and
              password  in  the  normal  way.  If str is "-" the stdin is read via getpass(3) for
              username@password.  Otherwise if str is a file, it is opened  and  the  first  line
              read  is taken as the Unix username and the 2nd as the password. If str prefixed by
              "rm:" the file is removed after reading. Otherwise, if str has a "@" character,  it
              is  taken as username@password. Otherwise, the program exits with an error. Got all
              that?

       -repeater str
              This   is   for   use   with    UltraVNC    repeater    proxy    described    here:
              http://www.uvnc.com/addons/repeater.html.  The "str" is the ID string to be sent to
              the repeater.  E.g. ID:1234 It can also be the hostname and port or display of  the
              VNC  server,  e.g.  12.34.56.78:0 or snoopy.com:1.  Note that when using -repeater,
              the host:dpy on the cmdline is the  repeater  server,  NOT  the  VNC  server.   The
              repeater will connect you.

              Example: vncviewer ... -repeater ID:3333 repeat.host:5900

              Example: vncviewer ... -repeater vhost:0 repeat.host:5900

              Use,  e.g.,  '-repeater  SCIII=ID:3210' if the repeater is a Single Click III (SSL)
              repeater (repeater_SSL.exe) and you are passing the  SSL  part  of  the  connection
              through  stunnel, socat, etc.  This way the magic UltraVNC string 'testB' needed to
              work with the repeater is sent to it.

       -rfbversion str
              Set the advertised RFB version.  E.g.: -rfbversion  3.6   For  some  servers,  e.g.
              UltraVNC this needs to be done.

       -ultradsm
              UltraVNC     has     symmetric     private    encryption    DSM    plugins.     See
              http://www.uvnc.com/features/encryption.html.  It is assumed you are using  a  unix
              program  (e.g.  our  ultravnc_dsm_helper)  to  encrypt and decrypt the UltraVNC DSM
              stream. IN ADDITION TO THAT supply -ultradsm to tell THIS viewer to modify the  RFB
              data  sent  so  as to work with the UltraVNC Server.  For some reason, each RFB msg
              type must be sent twice under DSM.

       -mslogon user
              Use Windows MS Logon to an UltraVNC server.  Supply  the  username  or  "1"  to  be
              prompted.  The default is to autodetect the UltraVNC MS Logon server and prompt for
              the username and password.

              IMPORTANT NOTE: The UltraVNC MS-Logon Diffie-Hellman exchange is very weak and  can
              be brute forced to recover your username and password in a few seconds of CPU time.
              To be safe, be sure to use an additional encrypted tunnel (e.g. SSL or SSH) for the
              entire VNC session.

       -chatonly
              Try  to  be a client that only does UltraVNC text chat. This mode is used by x11vnc
              to present a chat window on the physical X11 console (i.e. to chat with the  person
              at the display).

       -env VAR=VALUE
              To save writing a shell script to set environment variables, specify as many as you
              need on the command  line.   For  example,  -env  SSVNC_MULTIPLE_LISTEN=MAX:5  -env
              EDITOR=vi

       -noipv6
              Disable all IPv6 sockets.  Same as VNCVIEWER_NO_IPV6=1.

       -noipv4
              Disable all IPv4 sockets.  Same as VNCVIEWER_NO_IPV4=1.

       -printres
              Print out the Ssvnc X resources (appdefaults) and then exit. You can save them to a
              file and customize them (e.g. the keybindings and Popup menu)  Then  point  to  the
              file via XENVIRONMENT or XAPPLRESDIR.

       -pipeline
              Like  TurboVNC,  request the next framebuffer update as soon as possible instead of
              waiting until  the  end  of  the  current  framebuffer  update  coming  in.   Helps
              'pipeline' the updates.  This is currently the default, use -nopipeline to disable.

       -appshare
              Enable  features  for use with x11vnc's -appshare mode where instead of sharing the
              full desktop only the application's windows are shared.  Viewer multilisten mode is
              used  to  create  the  multiple  windows:  -multilisten  is  implied.   See 'x11vnc
              -appshare -help' more information on the mode.   Features  enabled  in  the  viewer
              under  -appshare  are:  Minimum  extra  text in the title, auto -ycrop is disabled,
              x11vnc -remote_prefix X11VNC_APPSHARE_CMD: message channel, x11vnc  initial  window
              position hints.  See also Escape Keys below for additional key and mouse bindings.

       -escape str
              This  sets  the 'Escape Keys' modifier sequence and enables escape keys mode.  When
              the modifier keys escape sequence is held down, the next keystroke  is  interpreted
              locally to perform a special action instead of being sent to the remote VNC server.

              Use  '-escape default' for the default modifier sequence.  (Unix: Alt_L,Super_L and
              MacOSX: Control_L,Meta_L)

              Here are the 'Escape Keys: Help+Set' instructions from the Popup:

              Escape Keys:  Enter a comma separated list of  modifier  keys  to  be  the  'escape
              sequence'.   When  these  keys  are  held  down,  the next keystroke is interpreted
              locally to invoke a special action instead of being sent to the remote VNC  server.
              In other words, a set of 'Hot Keys'.

              Here is the list of local key mappings to special actions:

              r: refresh desktop  b: toggle bell  c: toggle full-color

              f: file transfer    x: x11cursor    z: toggle Tight/ZRLE

              l: full screen      g: graball      e: escape keys dialog

              s: scale dialog     +: scale up (=) -: scale down (_)

              t: text chat                        a: alphablend cursor

              V: toggle viewonly  Q: quit viewer  123456: UltraVNC scale 1/n

              Arrow keys: pan the viewport about 10% for each keypress.

              PageUp/PageDown: pan the viewport by a screenful vertically.

              Home/End: pan the viewport by a screenful horizontally.

              KeyPad Arrows: pan the viewport by 1 pixel for each keypress.

              Dragging the Mouse with Button1 pressed also pans the viewport.

              Clicking Mouse Button3 brings up the Popup Menu.

              The  above  mappings  are always active in ViewOnly mode, unless you set the Escape
              Keys value to 'never'.

              x11vnc -appshare hot-keys:  x11vnc has  a  simple  application  sharing  mode  that
              enables  the viewer-side to move, resize, or raise the remote toplevel windows.  To
              enable it, hold down Shift + the Escape Keys and press these:

              Arrow keys: move the remote window around in its desktop.

              PageUp/PageDn/Home/End:  resize the remote window.

              +/-: raise or lower the remote window.

              M or Button1 move win to local position;  D or Button3: delete remote win.

              If the Escape Keys value below is set to  'default'  then  a  default  list  of  of
              modifier  keys  is  used.   For  Unix  it  is:  Alt_L,Super_L  and for MacOSX it is
              Control_L,Meta_L.  Note: the Super_L key usually has  a  Windows(TM)  Flag  on  it.
              Also note the _L and _R mean the key is on the LEFT or RIGHT side of the keyboard.

              On  Unix   the default is Alt and Windows keys on Left side of keyboard.  On MacOSX
              the default is Control and Command keys on Left side of keyboard.

              Example: Press and hold the Alt and Windows keys on the LEFT side of  the  keyboard
              and  then  press  'c'  to  toggle the full-color state.  Or press 't' to toggle the
              ultravnc Text Chat window, etc.

              To use something besides the default, supply a comma separated list  (or  a  single
              one)  from:  Shift_L  Shift_R Control_L Control_R Alt_L Alt_R Meta_L Meta_R Super_L
              Super_R Hyper_L Hyper_R or Mode_switch.

        New Popup actions:

               ViewOnly:                ~ -viewonly
               Disable Bell:            ~ -nobell
               Cursor Shape:            ~ -nocursorshape
               X11 Cursor:              ~ -x11cursor
               Cursor Alphablend:       ~ -alpha
               Toggle Tight/Hextile:    ~ -encodings hextile...
               Toggle Tight/ZRLE:       ~ -encodings zrle...
               Toggle ZRLE/ZYWRLE:      ~ -encodings zywrle...
               Quality Level            ~ -quality (both Tight and ZYWRLE)
               Compress Level           ~ -compresslevel
               Disable JPEG:            ~ -nojpeg  (Tight)
               Pipeline Updates         ~ -pipeline

               Full Color                 as many colors as local screen allows.
               Grey scale (16 & 8-bpp)  ~ -grey, for low colors 16/8bpp modes only.
               16 bit color (BGR565)    ~ -16bpp / -bgr565
               8  bit color (BGR233)    ~ -bgr233
               256 colors               ~ -bgr233 default # of colors.
                64 colors               ~ -bgr222 / -use64
                 8 colors               ~ -bgr111 / -use8
               Scale Viewer             ~ -scale
               Escape Keys: Toggle      ~ -escape
               Escape Keys: Help+Set    ~ -escape
               Set Y Crop (y-max)       ~ -ycrop
               Set Scrollbar Width      ~ -sbwidth
               XGrabServer              ~ -graball

               UltraVNC Extensions:

                 Set 1/n Server Scale     Ultravnc ext. Scale desktop by 1/n.
                 Text Chat                Ultravnc ext. Do Text Chat.
                 File Transfer            Ultravnc ext. File xfer via Java helper.
                 Single Window            Ultravnc ext. Grab and view a single window.
                                          (select then click on the window you want).
                 Disable Remote Input     Ultravnc ext. Try to prevent input and
                                          viewing of monitor at physical display.

               Note: the Ultravnc extensions only apply to servers that support
                     them.  x11vnc/libvncserver supports some of them.

               Send Clipboard not Primary  ~ -sendclipboard
               Send Selection Every time   ~ -sendalways

ENCODINGS

       The server supplies information in whatever format is desired by the client, in  order  to
       make the client as easy as possible to implement.  If the client represents itself as able
       to use multiple formats, the server will choose one.

       Pixel format refers to the representation of an individual pixel. The most common  formats
       are  24  and  16  bit "true-color" values, and 8-bit "color map" representations, where an
       arbitrary map converts the color number to RGB values.

       Encoding refers to how a rectangle of pixels are sent (all pixel  information  in  VNC  is
       sent as rectangles). All rectangles come with a header giving the location and size of the
       rectangle and an encoding type used by the data which  follows.  These  types  are  listed
       below.

       Raw    The  raw  encoding simply sends width*height pixel values. All clients are required
              to support this encoding type. Raw is also the fastest when the server  and  viewer
              are  on  the  same machine, as the connection speed is essentially infinite and raw
              encoding minimizes processing time.

       CopyRect
              The Copy Rectangle encoding is efficient when something is being  moved;  the  only
              data  sent  is  the location of a rectangle from which data should be copied to the
              current location. Copyrect could also be used to efficiently  transmit  a  repeated
              pattern.

       RRE    The  Rise-and-Run-length-Encoding  is basically a 2D version of run-length encoding
              (RLE). In this encoding, a sequence of identical pixels are compressed to a  single
              value  and  repeat  count. In VNC, this is implemented with a background color, and
              then specifications of an arbitrary number of subrectangles  and  color  for  each.
              This is an efficient encoding for large blocks of constant color.

       CoRRE  This is a minor variation on RRE, using a maximum of 255x255 pixel rectangles. This
              allows for single-byte values to be used, reducing packet size. This is in  general
              more  efficient, because the savings from sending 1-byte values generally outweighs
              the losses from the (relatively rare) cases where very large  regions  are  painted
              the same color.

       Hextile
              Here,  rectangles are split up in to 16x16 tiles, which are sent in a predetermined
              order. The data within the tiles is sent either raw or as a variant on RRE. Hextile
              encoding  is  usually  the best choice for using in high-speed network environments
              (e.g. Ethernet local-area networks).

       Zlib   Zlib is a very simple encoding that uses zlib library to compress raw  pixel  data.
              This  encoding  achieves  good compression, but consumes a lot of CPU time. Support
              for this encoding is provided for compatibility with VNC  servers  that  might  not
              understand Tight encoding which is more efficient than Zlib in nearly all real-life
              situations.

       Tight  Like Zlib encoding, Tight encoding uses zlib library to compress  the  pixel  data,
              but it pre-processes data to maximize compression ratios, and to minimize CPU usage
              on compression. Also, JPEG compression may be  used  to  encode  color-rich  screen
              areas  (see  the description of -quality and -nojpeg options above). Tight encoding
              is usually the best choice for low-bandwidth network environments (e.g. slow  modem
              connections).

       ZRLE   The SSVNC viewer has ported the RealVNC (www.realvnc.com) ZRLE encoding to the unix
              tightvnc viewer.

       ZYWRLE The SSVNC viewer has ported the Hitachi lossy  wavelet  based  ZRLE  encoding  from
              http://mobile.hitachi-system.co.jp/publications/ZYWRLE/   to   the   unix  tightvnc
              viewer.

RESOURCES

       X resources that vncviewer knows about,  aside  from  the  normal  Xt  resources,  are  as
       follows:

       shareDesktop
              Equivalent of -shared/-noshared options. Default true.

       viewOnly
              Equivalent of -viewonly option. Default false.

       fullScreen
              Equivalent of -fullscreen option. Default false.

       grabKeyboard
              Grab  keyboard  in  full-screen  mode.  This can help to solve problems with losing
              keyboard focus. Default false.

       raiseOnBeep
              Equivalent of -noraiseonbeep option, when set to false. Default true.

       passwordFile
              Equivalent of -passwd option.

       userLogin
              Equivalent of -user option.

       passwordDialog
              Whether to use a dialog box to get the password (true)  or  get  it  from  the  tty
              (false). Irrelevant if passwordFile is set. Default false.

       encodings
              Equivalent of -encodings option.

       compressLevel
              Equivalent of -compresslevel option (TightVNC-specific).

       qualityLevel
              Equivalent of -quality option (TightVNC-specific).

       enableJPEG
              Equivalent of -nojpeg option, when set to false. Default true.

       useRemoteCursor
              Equivalent of -nocursorshape option, when set to false (TightVNC-specific). Default
              true.

       useBGR233
              Equivalent of -bgr233 option. Default false.

       nColours
              When using BGR233, try to allocate this many "exact" colors from the  BGR233  color
              cube.  When using a shared colormap, setting this resource lower leaves more colors
              for other X clients. Irrelevant when using truecolor. Default is 256 (i.e.  all  of
              them).

       useSharedColours
              If the number of "exact" BGR233 colors successfully allocated is less than 256 then
              the rest are filled in using the "nearest" colors  available.  This  resource  says
              whether  to  only use the "exact" BGR233 colors for this purpose, or whether to use
              other clients' "shared" colors as well.  Default  true  (i.e.  use  other  clients'
              colors).

       forceOwnCmap
              Equivalent of -owncmap option. Default false.

       forceTrueColour
              Equivalent of -truecolour option. Default false.

       requestedDepth
              Equivalent of -depth option.

       useSharedMemory
              Use  MIT  shared  memory  extension if on the same machine as the X server. Default
              true.

       wmDecorationWidth, wmDecorationHeight
              The total width and height taken up by window manager decorations.  This is used to
              calculate  the  maximum  size of the VNC viewer window.  Default is width 4, height
              24.

       bumpScrollTime, bumpScrollPixels
              When in full screen mode and  the  VNC  desktop  is  bigger  than  the  X  display,
              scrolling happens whenever the mouse hits the edge of the screen. The maximum speed
              of scrolling is bumpScrollPixels  pixels  every  bumpScrollTime  milliseconds.  The
              actual  speed  of  scrolling  will be slower than this, of course, depending on how
              fast your machine is.  Default 20 pixels every 25 milliseconds.

       popupButtonCount
              The number of buttons in the popup window. See the README file for more information
              on how to customize the buttons.

       debug  For debugging. Default false.

       rawDelay, copyRectDelay
              For debugging, see the README file for details. Default 0 (off).

ENVIRONMENT

       When  started  with the -via option, vncviewer reads the VNC_VIA_CMD environment variable,
       expands patterns beginning with the "%"  character,  and  executes  result  as  a  command
       assuming  that  it  would create TCP tunnel that should be used for VNC connection. If not
       set, this environment variable defaults to "/usr/bin/ssh -f -L %L:%H:%R %G sleep 20".

       The following patterns are recognized in the VNC_VIA_CMD (note that all the  patterns  %G,
       %H, %L and %R must be present in the command template):

       %%     A literal "%";

       %G     gateway host name;

       %H     remote VNC host name, as known to the gateway;

       %L     local TCP port number;

       %R     remote TCP port number.

SEE ALSO

       vncserver(1),   x11vnc(1),   ssvnc(1),   Xvnc(1),   vncpasswd(1),  vncconnect(1),  ssh(1),
       http://www.karlrunge.com/x11vnc, http://www.karlrunge.com/x11vnc/ssvnc.html

AUTHORS

       Original VNC  was  developed  in  AT&T  Laboratories  Cambridge.  TightVNC  additions  was
       implemented  by  Constantin  Kaplinsky.  Many  other  people  participated in development,
       testing and support.   Karl  J.  Runge  added  all  of  the  SSVNC  related  features  and
       improvements.

       Man page authors:
       Marcus Brinkmann <Marcus.Brinkmann@ruhr-uni-bochum.de>,
       Terran Melconian <terran@consistent.org>,
       Tim Waugh <twaugh@redhat.com>,
       Constantin Kaplinsky <const@ce.cctpu.edu.ru>
       Karl J. Runge <runge@karlrunge.com>

                                            April 2010                             ssvncviewer(1)