LIBXRX(1)LIBXRX(1)NAMElibxrx - RX Web Browser Plug-in
DESCRIPTION
The RX Plug-in may be used with web browsers in the Mozilla family,
including Netscape Navigator (3.0 or later), Firefox, and SeaMonkey, to
interpret documents in the RX MIME type format and start remote appli‐
cations.
The RX Plug-in reads an RX document, from which it gets the list of
services the application wants to use. Based on this information, the
RX Plug-in sets the various requested services, including creating
authorization keys if your X server supports the SECURITY extension. It
then passes the relevant data, such as the X display name, to the
application through an HTTP GET request of the associated CGI script.
The Web server then executes the CGI script to start the application.
The client runs on the web server host connected to your X server. In
addition when the RX document is used within the EMBED tag (a Netscape
extension to HTML), the RX Plug-in uses the XC-APPGROUP extension, if
it is supported by your X server, to cause the remote application to be
embedded within the browser page from which it was launched.
INSTALLATION
To install the RX Plug-in so that the web browser can use it, find the
file named libxrx.so or libxrx.sl (or similar, depending on your plat‐
form) in __ProjectRoot__/lib and copy it to the browser plugin direc‐
tory in the system installation or your home directory (such as
/usr/lib/firefox/plugins or $HOME/.firefox/plugins).
If you have configured the web browser to use the RX helper program
(xrx), you must reconfigure it. Generally you simply need to remove or
comment out the line you may have previously added in your mailcap file
to use the RX helper program. Otherwise the plug-in will not be
enabled. (The usual comment character for mailcap is ``#''.)
If you are already running the web browser, you need to exit and
restart it after copying the plug-in library so the new plug-in will be
found. Once this is done you can check that the browser has success‐
fully loaded the plug-in by checking the ``About Plug-ins'' page from
the Help menu. This should show something like:
RX Plug-in
File name: /usr/local/lib/netscape/plugins/libxrx.sl.6.3
X Remote Activation Plug-in
Mime Type Description Suffixes Enabled
application/x-rx X Remote Activation Plug-in xrx Yes
Once correctly configured, the web browser will activate the RX Plug-in
whenever you retrieve any document of the MIME type application/x-rx.
RESOURCES
The RX Plug-in looks for resources associated with the widget net‐
scape.Navigator (class Netscape.TopLevelShell) and understands the fol‐
lowing resource names and classes:
xrxHasFirewallProxy (class XrxHasFirewallProxy)
Specifies whether an X server firewall proxy (see xfwp) is run‐
ning and should be used. Default is ``False.'' The X firewall
proxy uses the X Security Extension and this extension will
only allow clients to connect to the X server if host-based
authentication is turned on. See xfwp(1) for more information.
xrxInternalWebServers (class XrxInternalWebServers)
The web servers for which the X server firewall proxy should
not be used (only relevant when xrxHasFirewallProxy is
``True''). Its value is a comma separated list of mask/value
pairs to be used to filter internal web servers, based on their
address. The mask part specifies which segments of the address
are to be considered and the value part specifies what the
result should match. For instance the following list:
255.255.255.0/198.112.45.0, 255.255.255.0/198.112.46.0
matches the address sets: 198.112.45.* and 198.112.46.*. More
precisely, the test is (address & mask) == value.
xrxFastWebServers (class XrxFastWebServers)
The web servers for which LBX should not be used. The resource
value is a list of address mask/value pairs, as previously
described.
xrxTrustedWebServers (class XrxTrustedWebServers)
The web servers from which remote applications should be run as
trusted clients. The default is to run remote applications as
untrusted clients. The resource value is a list of address
mask/value pairs, as previously described.
ENVIRONMENT
If the RX document requests X-UI-LBX service and the default X server
does not advertise the LBX extension, the RX Plug-in will look for the
environment variable ``XREALDISPLAY'' to get a second address for your
X server and look for the LBX extension there. When running your
browser through lbxproxy you will need to set XREALDISPLAY to the
actual address of your server if you wish remote applications to be
able to use LBX across the Internet.
If the RX document requests XPRINT service, RX Plug-in looks for the
variable ``XPRINTER'' to get the printer name and X Print server
address to use. If the server address is not specified as part of
XPRINTER, RX Plug-in uses the first one specified through the variable
``XPSERVERLIST'' when it is set. When it is not RX Plug-in then tries
to use the video server as the print server. If the printer name is not
specified via XPRINTER, RX Plug-in looks for it in the variables
``PDPRINTER'', then ``LPDEST'', and finally ``PRINTER'',
Finally, if you are using a firewall proxy, RX Plug-in will look for
``PROXY_MANAGER'' to get the address of your proxy manager (see proxym‐
ngr). When not specified it will use ":6500" as the default.
KNOWN BUG
When an authorization key is created for a remote application to use
the X Print service, the RX Plug-in has to create the key with an infi‐
nite timeout since nobody knows when the application will actually con‐
nect to the X Print server. It then revokes the key when its instance
is destroyed (that is when you go to another page). However, if the
Plug-in does not get destroyed properly, which happens when the browser
dies unexpectedly, the print authorization key will never get revoked.
SEE ALSO
xrx (1), xfwp (1), lbxproxy (1), proxymngr (1), The RX Document speci‐
fication
AUTHORS
Arnaud Le Hors and Kaleb Keithley, X Consortium
X Version 11 xrx 1.0.2 LIBXRX(1)
