Setting Up to Display Graphics to Your Local Screen

To execute MPI programs that display graphics to your screen (e.g., the Mandelbrot Renderer), you will need to perform the following two steps:

1. On your local machine at which you want to display the image from porsche, create a file, called addhosts, that contains the following lines. Make the file addhosts executable by typing

   chmod 755 addhosts
   

   at the UNIX prompt. Each time you login to your local machine, and want to display graphics from the cluster, execute the addhosts file by typing

   addhosts
   

   at the UNIX prompt on your local machine. The addhosts file adds each of the machines in the cluster to your local machine's list of machines that have permission to display to your local screen. You can copy this file from ~pollock/public/addhosts on porsche.

   # sample addhosts file
   xhost +porsche.cis.udel.edu 
   xhost +cobra.cis.udel.edu 
   xhost +corvette.cis.udel.edu 
   xhost +ferrari.cis.udel.edu
   xhost +jaguar.cis.udel.edu
   xhost +lamborghini.cis.udel.edu 
   xhost +lotus.cis.udel.edu
   xhost +maserati.cis.udel.edu
   xhost +viper.cis.udel.edu
   

2. Each time you are logged onto porsche and want to run a parallel program that displays to your local screen, you need to type:

   setenv DISPLAY localmachinename:0.0

   where localmachinename is replaced by the full name of the machine or xterm at which you are sitting (e.g., quadriga.cis.udel.edu). This command only has to be executed once when you login. Afterward, any graphic images generated by the DEC Alpha client machines and sent to porsche will be passed on to your local machine for display.

   To find out the name of the xterm which you are using, you can do either of the following:

   • Press the Shift and HELP keys simultaneously, or
   • Type echo $DISPLAY.