About X frame buffer
Xvfb is an X Windows server that has neither a graphics card nor a physical graphics display. BIRT iHub uses the X server for font-rendering information and to generate graphics in documents. Typically, an X server requires a graphics card and physical graphics display on the iHub machine, but you can use Xvfb in place of these components.
The Xvfb software installed with BIRT iHub includes Type 1 fonts. Actuate maps these fonts to Microsoft Windows fonts for consistent graphics rendering on the various platforms.
The Xvfb software uses:
X libraries installed on the BIRT iHub machine
If you choose to install Xvfb, the installation script searches for the required libraries and displays a message if the install script cannot find the required libraries on the machine.
Variables set to the path of the Xvfb libraries
XVFBDISPLAY variable in start_srvr.sh.
display_value in pmd11.sh.
To view and print the documents from BIRT iHub, you need to set these variables only if you install Xvfb software.
The DISPLAY environment variable specifies the X Windows server used by the iHub machine. For example, if the iHub machine is running X Windows, it sets DISPLAY to the local machine:
# setenv DISPLAY :0.0
If you use a separate machine as the X Windows server, specify the machine name in the environment variable DISPLAY. The following example sets DISPLAY to use an X Windows server on a machine named urup:
# setenv DISPLAY urup:0.0
The original source code for Xvfb is included as a component of X11R6, but not in earlier X Window system releases.