- Hewlett-Packard Printer User Guide

Using the Integration Capabilities of the VPO Motif-based GUI
Integrating External Applications into the VPO GUI
Chapter 3 151
For all three types of VPO application, you must define a user name. In
addition, for applications that use an input/output window, the user’s
password is required. The user name, used to run the application, can be
different for the same application for each of the operators.
The following is a description of the user/password mechanisms used in
VPO:
❏ VPO application with No Window option (e.g. X application):
You need to define a user name but no password. When starting the
application, VPO sends an RPC request to the action agent. The
action agent, always running as root, switches to the appropriate user
on the managed node, sets the DISPLAY variable, and starts the
application.
This is mainly used for X-applications, however, you can also use it
for terminal applications if a terminal emulator is available on the
managed nodes. In this case, you need to specify this in the
application call, for example:
/usr/bin/X11/hpterm -e “ls -l /tmp”
❏ VPO application with Output only - Window option:
You need to define a user name but no password. When starting the
application VPO opens a dialog box on the display and sends an RPC
request to the action agent. The action agent locally switches to the
appropriate user, executes the application, sends the output, using an
RPC, back to the management server and displays it in the dialog
box.
This is appropriate for the integration of applications which do not
require interaction, for example, operating system commands like ps,
bdf, and so on.
❏ VPO application with Input/Output - Window option:
You need to define both a user name and a password. When starting
the application, VPO opens a terminal locally on the management
server and uses an rlogin mechanism, with the defined user and
password, to connect to the managed node. The user profile is
executed and the application is started. When the application has
finished, the connection is closed automatically after the operator has
pressed Return or other signal.