WinVNC is fairly simple to install and even easier to use. This will install the default hooks settings, which are tweaked to cope with some common, uncooperative applications, such as the clock. See later for more information about the registry settings. WinVNC can now be run from the Start menu. Clicking on this icon with the right mouse button will cause a menu to be displayed, with the following options on it: Properties - This will cause the Properties dialog to be displayed, allowing the user to change various WinVNC parameters.
Kill All Clients - This will disconnect all currently connected clients from the server. Close - Shutdown the server. Incoming Connections Accept Socket Connections - The server normally accepts direct, socket-based connections from the vncviewer program.
See ORL internal version info. For the public version, clearing this will disable any incoming connections. Display Number - This allows the user to specify the display number which the server will use. There is normally no need to change this from the default of zero. Auto - This tick box indicates to WinVNC whether it should use the display number specified in the Display Number box, or whether it should use the first display number not already in use on the server machine.
Password - Incoming connections must be authenticated to verify that the person connecting is allowed to connect to this machine. This text box allows your password to be specified for authentication. Update Handling. Note that clicking in a window will generally cause it to be updated, so if you have certain applications which don't update very well, try this! For this reason, it is sometimes useful to be able to poll the entire screen in order to check for changes, sacrificing performance for accuracy.
Poll Foreground Window - Polling only the currently selected window for changes is less CPU intensive than full-screen polling and often gives similar results, for example when using the Command Prompt, which is not normally compatible with WinVNC. Poll Window Under Cursor - A variation on Poll Foreground Window, this option causes the window under the mouse cursor to be polled for changes.
Both options may be enabled simultaneously if required. Poll Console Windows Only - When this option is set, the only windows which will be ever be polled are Command Prompts. This works well in conjunction with Poll Window Under Cursor, to use polling only when the cursor is over a console window.
Poll On Event Received Only - When this option is set, the screen will only be polled for updates when a mouse or keyboard event is received from the remote client. This is provided for low bandwidth networks, where it may be useful to control how often the screen is polled and changes sent.
The user's settings are saved into the user-specific section of the registry when WinVNC quits, meaning that they will be used next time you run WinVNC. As of Version 3. AuthRequired By default, all WinVNC servers will not accept incoming connections unless the server has had it's password field set to a non-null value. This restriction was placed to ensure that misconfigured servers would not open security loopholes without the user realising.
If a server is only to be used on a secure LAN, however, it may be desirable to forego such checking and allow machines to have a null password. Setting this registry value to zero will disable null-password checking by WinVNC. For testing purposes, or, potentially, when using multiple instances of WinVNC on Windows Terminal Server, this behaviour is undesirable.
Setting this registry entry to 1 will cause local-loopback connections to be allowed. Setting it to zero will filter out such connections. DebugLevel DebugMode Run-time logging of all internal debug messages is now supported. Log data may be output to a file or a console window or the MSVC debugger if the program was compiled with debugging active.
DebugLevel indicates how much debug information to present. Any positive integer is valid. Zero indicates that no debugging information should be produced and is the default. A value of around will cause full debugging output to be produced. ConnectPriority By default, all WinVNC servers will disconnect any existing connections when an incoming, non-shared connection is authenticated.
This behaviour is undesirable when the server machine is being used as a shared workstation by several users or when remoting a single display to multiple clients for vewing, as in a classroom situation. WinVNC uses a special library, VNCHooks, to hook into the other running applications and retrieve notifications of areas of the screen being changed. The VNCHooks library uses the messages sent to visible Windows to decide which areas need considering for update. Not all applications use the same method of updating the screen, so you can tweak the method used by WinVNC for particular applications by editing the registry.
All the entries listed can be found under. The service support is still in the early stages of development, and the following 'features' should also be pointed out:. Windows NT 'features': There will be one password for the machine, rather than one per user. The system tray icon is not always correctly displayed, so you won't always be able to tell whether someone else is connected except by the fact that things work more slowly. To interact with the application from another machine on the network, run a VNC client pointing to the machine that is running the server application.
Qt for Embedded Linux will create a by pixel display by default. If you want to run more than one application on the same display, you only need to start the first one as a server application, using the -qws command line option to indicate that it will manage other windows. Subsequent client applications can be started without the -qws option, but will each require the same -display option and argument as those used for the server.
However, for the clients, this option will not cause a new VNC server to be started, but only indicates that their windows will appear on the virtual screen managed by the server application. It is not always necessary to specify the -qws command line option when running a server application as long as the QApplication object used by the application has been constructed with the QApplication::GuiServer flag.
See the running applications documentation for more details about server and client applications. The virtual framebuffer is an alternative technique recommended for development and debugging purposes. The virtual framebuffer emulates a framebuffer using a shared memory region and the qvfb tool to display the framebuffer in a window.
Its use of shared memory makes the virtual framebuffer much faster and smoother than using the VNC protocol, but it does not operate over a network. Documentation contributions included herein are the copyrights of their respective owners. Documentation sources may be obtained from www. All other trademarks are property of their respective owners.