NAME    [Toc]    [Back]

       XRX - helper program

SYNOPSIS    [Toc]    [Back]

       xrx [-toolkitoption...]  filename

DESCRIPTION    [Toc]    [Back]

       The  helper  program  may  be used with any Web browser to
       interpret documents in the RX MIME type format  and  start
       remote applications.

       xrx  reads  in  the RX document specified by its filename,
       from which it gets the list of  services  the  application
       wants to use. Based on this information, xrx 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.

INSTALLATION    [Toc]    [Back]

       You need to configure your web browser to use xrx  for  RX
       documents.   Generally   the   following   line   in  your
       $HOME/.mailcap is enough:       application/x-rx; xrx %s

       However, you may need to refer to your web browser's documentation
  for  exact  instructions  on configuring helper
       applications.

       Once correctly configured, your browser will activate  the
       helper  program  whenever you retrieve any document of the
       MIME type application/x-rx.

OPTIONS    [Toc]    [Back]

       The xrx helper program  accepts  all  of  the  standard  X
       Toolkit  command  line options such as: This option specifies
 a resource string to be used. There  may  be  several
       instances of this option on the command line.

RESOURCES    [Toc]    [Back]

       The  application  class name of the xrx program is Xrx and
       it understands the following  application  resource  names
       and  classes: Specifies whether an X server firewall proxy
       (see xfwp) is running  and  should  be  used.  Default  is
       ``False.'' 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.
       The web servers for which LBX  should  not  be  used.  The
       resource  value  is a list of address mask/value pairs, as
       previously described.  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    [Toc]    [Back]

       The xrx helper program uses  the  standard  X  environment
       variables  such as ``DISPLAY'' to get the default X server
       host and display number. If the RX document requests X-UILBX
  service  and  the default X server does not advertise
       the LBX extension, xrx 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, xrx 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,  xrx uses the first one
       specified through the variable ``XPSERVERLIST'' when it is
       set. When it is not xrx then tries to use the video server
       as the print server. If the printer name is not  specified
       via   XPRINTER,   xrx   looks  for  it  in  the  variables
       ``PDPRINTER'', then ``LPDEST'', and finally ``PRINTER''

       If you are using a  firewall  proxy,  xrx  will  look  for
       ``PROXY_MANAGER'' to get the address of your proxy manager
       (see proxymngr).  When not specified it will  use  ":6500"
       as the default.

KNOWN BUG    [Toc]    [Back]

       When an authorization key is created for a remote application
 to use the X Print service, the helper program has to
       create the key with an infinite timeout since nobody knows
       when the application will actually connect to the X  Print
       server.  Therefore, in this case, the helper program stays
       around to revoke the key when the  application  goes  away
       (that  is  when  its  video  key expires). However, if the
       helper program dies unexpectedly the  print  authorization
       key will never get revoked.

SEE ALSO    [Toc]    [Back]

       lbxproxy (1),

       The RX Document specification

AUTHOR    [Toc]    [Back]

       Arnaud Le Hors, X Consortium



                                                           XRX(1)