directvnc(1)						      General Commands Manual						      directvnc(1)

NAME

       directvnc - a vnc client for the linux framebuffer device

SYNOPSIS

       directvnc server:display [options]

DESCRIPTION

       DirectVNC  is  a  client  implementing  the remote framebuffer protocol (rfb) which is used by VNC servers. If a VNC server is running on a
       machine you can connect to it using this client and have the contents of its display shown on your screen. Keyboard and	mouse  events  are
       sent  to  the  server,  so  you can basically control a VNC server remotely. There are servers (and other clients) freely available for all
       operating systems.

       What makes DirectVNC different from other unix vnc clients is that it uses the linux framebuffer device through the DirectFB library  which
       enables	it  to	run on anything that has a framebuffer without the need for a running X server.  This includes embedded devices.  DirectFB
       even uses acceleration features of certain graphics cards. Thus a lot of configuration can be done by creating the library specific config-
       uration	file /etc/directfbrc or the program-specific configuration file /etc/directfbrc.directvnc. See directfbrc(5) or find out all about
       DirectFB here:

	   www.directfb.org

       DirectVNC basically provides a very thin VNC client for unix framebuffer systems.

QUITTING

       Hitting <ctrl-q> exits the viewer.

OPTIONS

       -h, --help
	    display help output and exit

       -v, --version
	    output version information and exit

       -p, --password
	    password string to be passed to the server for authentication. Use this with care!

       -b, --bpp
	    the bits per pixel to be used by the client. Currently only 16 and 24 bpp are available.

       -e --encodings
	    DirectVNC 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.
	    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.

       -f --pollfrequency
	    time in ms to wait between polls for screen updates when no events are to be processed. This reduces cpu and network load. Default	is
	    50 ms.

       -s, --shared (default)
	    Don't disconnect already connected clients.

       -n, --noshared
	    Disconnect already connected clients.

       -n, --nolocalcursor
	    Disable  local  cursor  tracking  By default, and if the server is capable of the SoftCursor encoding, mouse movements do not generate
	    framebuffer updates and the cursor state is kept locally. This removes mouse pointer lag and lets the connection appear faster.

       -c --compresslevel level
	    Use specified compression level (0..9) for "tight" and "zlib" encodings (only usable with servers capable of those encodings).   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.

       -q --quality level
	    Use  the  specified image quality level (0..9) for "tight" encoding (only usable with servers capable of those encodings).	Specifying
	    this option allows "tight" encoder to use lossy JPEG compression.  Quality level 0 denotes bad image quality but very impressive  com-
	    pression  ratios,  while  level  9	offers very good image quality at lower compression ratios. Note that "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.

       -m --modmap PATH
	    Path  to  the  modmap  (subset  of X-style) file to load. With this option, it is possible to set an alternative keyboard layout, with
	    ability to support non-latin characters such as Cyrillic. A plain text file, containing a subset of xmodmap(1)  syntax  (only  keycode
	    expressions are recognized with up to four KEYSYMNAMEs) can be converted into the format that directvnc understands, and can be loaded
	    upon directvnc startup with this option. See directvnc-kbmapping(7).

LIMITATIONS

       At the moment, it is still necessary to use the --bpp command line option to set color depth. When negotiating with the remote  VNC  server
       side,  color  depth supplied by the server will be used. It is therefore necessary to make sure (at least in the present) that screen color
       depth (default, or set in the DirectFB configuration file), color depth supplied at the command line, and remote VNC server color depth all
       match.

SEE ALSO

       directfbrc(5), directvnc-kbmapping(7), directvnc-xmapconv(1), xmodmap(1)

AUTHORS

       Till Adam, Dimitry Golubovsky, Malte S. Stretz, Loris Boillet and others, based on AT&T and tightvnc VNC implementations.

								    Mar 5, 2010 						      directvnc(1)