X windows
*********

xrsh and xssh
=============

xrsh,1 and xssh,1 are convenience programs which

 1. use rsh or ssh to connect to a remote system

 2. set DISPLAY appropriately on the remote system

 3. invoke xterm,1 or other X client on the remote system

 1. To get a window on a.nersc.gov, do

          xssh -auth ssh a.nersc.gov

     xssh is a ssh-capable replacement for xrsh.  You will need to ensure that your PATH on a.nersc.gov is set in .cshrc and that it included the directory with xterm lives.  For that reason, I suggest you move

          if ( -e /etc/cshrc.nersc ) then
            source /etc/cshrc.nersc
          endif

     from ~/.login to the end of ~/.cshrc.

     On a.nersc.gov, if you do

          echo $DISPLAY

     you will see it set to something like a:4.0.  This is a special display setting used by ssh for encrypting your X traffic.  Incidentally the encryption is only in effect between NERSC and the machine you ran xssh on. The traffic between this machine and your X terminal is still unencrypted.

 2. To start a window on another machine in the Unix Cluster with your AFS tokens carried over:

          xssh lupus

     With this invocation, the X traffic is not encrypted.  You may wish to insert these xssh commands into your .twmrc as follows

          menu "Programs"
          {
          "Machines"      f.title

          "lupus"         !"xssh lupus"
          "a.nersc.gov"   !"xssh -auth ssh a.nersc.gov"

          }