ivs(1)

NAME

ivs - part of the italc-client package

SYNOPSIS

ivs

DESCRIPTION

ivs is a frontend for the vnc connection between the two machines.

OPTIONS

-display disp

X11 server display to connect to, usually :0. The X server process must be running on same machine and support MIT-SHM. Equivalent to setting the DISPLAY environment variable to "disp".

-auth file

Set the X authority file to be "file", equivalent to setting the XAUTHORITY environment varirable to "file" before startup. See Xsecurity(7), xauth(1) man pages.

-id windowid

Show the window corresponding to <windowid> not the entire display. Warning: bugs! new toplevels missed!...

-flashcmap

In 8bpp indexed color, let the installed colormap flash as the pointer moves from window to window (slow).

-notruecolor

Force 8bpp indexed color even if it looks like TrueColor.

-visual n

Experimental option: probably does not do what you think. It simply *forces* the visual used for the framebuffer; this may be a bad thing... It is useful for testing and for some workarounds. n may be a decimal number, or 0x hex. Run xdpyinfo(1) for the values. One may also use "TrueColor", etc. see <X11/X.h> for a list. If the string ends in ":m" for better or for worse the visual depth is forced to be m.

-scale fraction

Scale the framebuffer by factor "fraction". Values less than 1 shrink the fb. Note: image may not be sharp and response may be slower. If "fraction" contains a decimal point "." it is taken as a floating point number, alternatively the notation "m/n" may be used to denote fractions, e.g. -scale 2/3.

Scaling Options: can be added after fraction via ":", to supply multiple ":" options use commas. If you just want a quick, rough scaling without blending, append ":nb" to "fraction" (e.g. -scale 1/3:nb). For compatibility with vncviewers the scaled width is adjusted to be a multiple of 4, to disable this use ":n4". More esoteric options: ":in" use interpolation scheme even when shrinking, ":pad", pad scaled width and height to be multiples of scaling denominator (e.g. 3 for 2/3).

-viewonly

All VNC clients can only watch (default off).

-shared

VNC display is shared (default off).

-once

Exit after the first successfully connected viewer disconnects, opposite of -forever. This is the Default.

-forever

Keep listening for more connections rather than exiting as soon as the first client(s) disconnect. Same as -many

-connect string

For use with "vncviewer -listen" reverse connections. If string has the form "host" or "host:port" the connection is made once at startup. Use commas for a list of host's and host:port's. If string contains "/" it is instead interpreted as a file to periodically check for new hosts. The first line is read and then the file is truncated.

-vncconnect

Monitor the VNC_CONNECT X property set by the standard VNC program vncconnect(1). When the property is set to host or host:port establish a reverse connection. Using xprop(1) instead of vncconnect may work, see FAQ.

-inetd

Launched by inetd(1): stdio instead of listening socket. Note: if you are not redirecting stderr to a log file (via shell 2> or -o option) you must also specify the -q option.

-allow addr1[,addr2..]

Only allow client connections from IP addresses matching the comma separated list of numerical addresses. Can be a prefix, e.g. "192.168.100." to match a simple subnet, for more control build libvncserver with libwrap support. If the list contains a "/" it instead is a interpreted as a file containing addresses or prefixes that is re-read each time a new client connects. Lines can be commented out with the "#" character in the usual way.

-localhost

Same as -allow 127.0.0.1

-viewpasswd string

Supply a 2nd password for view-only logins. The -passwd (full-access) password must also be supplied.

-passwdfile filename

Specify libvncserver -passwd via the first line of the file "filename" instead of via command line. If a second non blank line exists in the file it is taken as a view-only password (i.e. -viewpasswd) Note: this is a simple plaintext passwd, see also -rfbauth and -storepasswd below.

-storepasswd pass file

Store password "pass" as the VNC password in the file "file". Once the password is stored the program exits. Use the password via "-rfbauth file"

-accept string

Run a command (possibly to prompt the user at the X11 display) to decide whether an incoming client should be allowed to connect or not. "string" is an external command run via system(3) or some special cases described below. Be sure to quote "string" if it contains spaces, etc. If the external command returns 0 the client is accepted, otherwise the client is rejected. See below for an extension to accept a client view-only.

Environment: The RFB_CLIENT_IP environment variable will be set to the incoming client IP number and the port in RFB_CLIENT_PORT (or -1 if unavailable). Similarly, RFB_SERVER_IP and RFB_SERVER_PORT (the x11vnc side of the connection), are set to allow identification of the tcp virtual circuit. The x11vnc process id will be in RFB_X11VNC_PID, a client id number in RFB_CLIENT_ID, and the number of other connected clients in RFB_CLIENT_COUNT.

If "string" is "popup" then a builtin popup window is used. The popup will time out after 120 seconds, use "popup:N" to modify the timeout to N seconds (use 0 for no timeout)

If "string" is "xmessage" then an xmessage(1) invocation is used for the command.

Both "popup" and "xmessage" will present an option for accepting the client "View-Only" (the client can only watch). This option will not be presented if -viewonly has been specified, in which case the entire display is view only.

If the user supplied command is prefixed with something like "yes:0,no:*,view:3 mycommand ..." then this associates the numerical command return code with the actions: accept, reject, and accept-view-only, respectively. Use "*" instead of a number to indicate the default action (in case the command returns an unexpected value). E.g. "no:*" is a good choice.

Note that x11vnc blocks while the external command or or popup is running (other clients may see no updates during this period).

More -accept tricks: use "popupmouse" to only allow mouse clicks in the builtin popup to be recognized. Similarly use "popupkey" to only recognize keystroke responses. All 3 of the popup keywords can be followed by +N+M to supply a position for the popup window. The default is to center the popup window.

-gone string

As -accept string, except to run a user supplied command when a client goes away (disconnects). Unlike -accept, the command return code is not interpreted by x11vnc.

-noshm

Do not use the MIT-SHM extension for the polling. Remote displays can be polled this way: be careful this can use large amounts of network bandwidth. This is also of use if the local machine has a limited number of shm segments and -onetile is not sufficient.

-flipbyteorder

Sometimes needed if remotely polled host has different endianness. Ignored unless -noshm is set.

-onetile

Do not use the new copy_tiles() framebuffer mechanism, just use 1 shm tile for polling. Same as -old_copytile. Limits shm segments used to 3.

-blackout string

Black out rectangles on the screen. string is a comma separated list of WxH+X+Y type geometries for each rect.

-xinerama

If your screen is composed of multiple monitors glued together via XINERAMA, and that screen is non-rectangular this option will try to guess the areas to black out (if your system has libXinerama).

-o logfile

Write stderr messages to file "logfile" instead of to the terminal. Same as -logfile "file".

-rc filename

Use "filename" instead of $HOME/.x11vncrc for rc file.

-norc

Do not process any .x11vncrc file for options.

-h -help

Print this help text.

-V -version

Print program version (last modification date).

-q

Be quiet by printing less informational output to stderr. Same as -quiet.

-bg

Go into the background after screen setup. Messages to stderr are lost unless -o logfile is used. Something like this could be useful in a script: port=`ssh $host "x11vnc -display :0 -bg" | grep PORT` port=`echo "$port" | sed -e 's/PORT=//'` port=`expr $port - 5900` vncviewer $host:$port

-modtweak -nomodtweak

Option -modtweak automatically tries to adjust the AltGr and Shift modifiers for differing language keyboards between client and host. Otherwise, only a single key press/release of a Keycode is simulated (i.e. ignoring the state of the modifiers: this usually works for identical keyboards). Also useful in resolving cases where a Keysym is bound to multiple keys (e.g. "<" + ">" and "," + "<" keys). Default: -modtweak

-xkb

When in modtweak mode, use the XKEYBOARD extension (if it exists) to do the modifier tweaking.

-skip_keycodes string

Skip keycodes not on your keyboard but your X server thinks exist. Currently only applies to -xkb mode. "string" is a comma separated list of decimal keycodes. Use this option to help x11vnc in the reverse problem it tries to solve: Keysym -> Keycode(s) when ambiguities exist. E.g. -skip_keycodes 94,114

-add_keysyms

If a Keysym is received from a VNC viewer and that Keysym does not exist in the X server, then add the Keysym to the X server's keyboard mapping. Added Keysyms will be removed when exiting.

-clear_mods

At startup and exit clear the modifier keys by sending KeyRelease for each one. The Lock modifiers are skipped. Used to clear the state if the display was accidentally left with any pressed down.

-clear_keys

As -clear_mods, except try to release any pressed key. Note that this option and -clear_mods can interfere with a person typing at the physical keyboard.

-remap string

Read Keysym remappings from file named "string". Format is one pair of Keysyms per line (can be name or hex value) separated by a space. If no file named "string" exists, it is instead interpreted as this form: key1-key2,key3-key4,... See <X11/keysymdef.h> header file for a list of Keysym names, or use xev(1). To map a key to a button click, use the fake Keysyms "Button1", ..., etc. E.g. -remap Super_R-Button2

-norepeat -repeat

Option -norepeat disables X server key auto repeat when VNC clients are connected. This works around a repeating keystrokes bug (triggered by long processing delays between key down and key up client events: either from large screen changes or high latency). Note: your VNC viewer side will likely do autorepeating, so this is no loss unless someone is simultaneously at the real X display. Default: -repeat

-nofb

Ignore video framebuffer: only process keyboard and pointer. Intended for use with Win2VNC and x2vnc dual-monitor setups.

-nobell

Do not watch for XBell events. (no beeps will be heard) Note: XBell monitoring requires the XKEYBOARD extension.

-nosel

Do not manage exchange of X selection/cutbuffer between VNC viewers and the X server.

-noprimary

Do not poll the PRIMARY selection for changes to send back to clients. (PRIMARY is still set on received changes, however).

-nocursor

Do not have the VNC viewer show a local cursor.

-mouse

Draw a 2nd cursor at the current X pointer position.

-mouseX

As -mouse, but also draw an "X" when pointer is on root background.

-X

Shorthand for -mouseX -nocursor.

-xwarppointer

Move the pointer with XWarpPointer() instead of XTEST (try as a workaround if pointer behaves poorly, e.g. on touchscreens or other non-standard setups).

-cursorpos -nocursorpos

Option -cursorpos enables sending the X cursor position back to all vnc clients that support the TightVNC CursorPosUpdates extension. Default: -cursorpos

-buttonmap string

String to remap mouse buttons. Format: IJK-LMN, this maps buttons I -> L, etc., e.g. -buttonmap 13-31

Button presses can also be mapped to keystrokes: replace a button digit on the right of the dash with :<sym>: or :<sym1>+<sym2>: etc. for multiple keys. For example, if the viewing machine has a mouse-wheel (buttons 4 5) but the x11vnc side does not, these will do scrolls:
-buttonmap 12345-123:Prior::Next:
-buttonmap 12345-123:Up+Up+Up::Down+Down+Down:

See <X11/keysymdef.h> header file for a list of Keysyms, or use the xev(1) program. Note: mapping of button clicks to Keysyms may not work if -modtweak or -xkb is needed for the Keysym.

If you include a modifier like "Shift_L" the modifier's up/down state is toggled, e.g. to send "The" use :Shift_L+t+Shift_L+h+e: (the 1st one is shift down and the 2nd one is shift up). (note: the initial state of the modifier is ignored and not reset) To include button events use "Button1", ... etc.

-nodragging

Do not update the display during mouse dragging events (mouse motion with a button held down). Greatly improves response on slow setups, but you lose all visual feedback for drags, text selection, and some menu traversals.

-old_pointer

Do not use the new pointer input handling mechanisms. See check_input() and pointer() in source file for details.

-input_skip n

For the old pointer handling when non-threaded: try to read n user input events before scanning display. n < 0 means to act as though there is always user input.

-debug_pointer

Print debugging output for every pointer event.

-debug_keyboard

Print debugging output for every keyboard event. Same as -dp and -dk, respectively. Use multiple times for more output.

-defer time

Time in ms to wait for updates before sending to client [rfbDeferUpdateTime] Default: 30

-wait time

Time in ms to pause between screen polls. Used to cut down on load. Default: 30

-nap

Monitor activity and if low take longer naps between polls to really cut down load when idle. Default: off

-sigpipe string

Broken pipe (SIGPIPE) handling. "string" can be "ignore" or "exit". For "ignore" libvncserver will handle the abrupt loss of a client and continue, for "exit" x11vnc will cleanup and exit at the 1st broken connection. Default: "ignore".

-threads -nothreads

Whether or not to use the threaded libvncserver algorithm [rfbRunEventLoop] if libpthread is available Default: -nothreads

-fs f

If the fraction of changed tiles in a poll is greater than f, the whole screen is updated. Default: 0.75

-gaps n

Heuristic to fill in gaps in rows or cols of n or less tiles. Used to improve text paging. Default: 4

-grow n

Heuristic to grow islands of changed tiles n or wider by checking the tile near the boundary. Default: 3

-fuzz n

Tolerance in pixels to mark a tiles edges as changed. Default: 2

These options are passed to libvncserver:

-rfbport port

TCP port for RFB protocol

-rfbwait time

Max time in ms to wait for RFB client

-rfbauth passwd-file

Use authentication on RFB protocol (use 'storepasswd' to create a password file)

-passwd plain-password

Use authentication (use plain-password as password, USE AT YOUR RISK)

-deferupdate time

Time in ms to defer updates (default 40)

-desktop name

VNC desktop name (default "LibVNCServer")

-alwaysshared

Always treat new clients as shared

-nevershared

Never treat new clients as shared

-dontdisconnect

Don't disconnect existing clients when a new non-shared connection comes in (refuse new connection instead)

-httpdir dir-path

enable http server using dir-path home

-httpport portnum

Use portnum for http connection

-enablehttpproxy

Enable http proxy support

-progressive height

Enable progressive updating for slow links

icv was written by Tobias Doerffel <[email protected]>.

AUTHOR

This manual page was written by Steffen Joeris <[email protected]>, for the Debian project (but may be used by others).