Accessing CSIL from your MacOS system

Accessing CSIL from MacOS

To access CSIL from MacOS, you can use the Terminal command, and type the following, replacing cgaucho with your ECI/CSIL username, and csil-12 with any CSIL hostname from csil-01 through csil-48:

ssh -X cgaucho@csil-12.cs.ucsb.edu

What about the no $DISPLAY environment variable error?

If you find when you type idle3 to bring up IDLE that you get this message:

no display name and no $DISPLAY environment variable

then you need to install XQuartz as explained below, log out, log in, and try again.

Installing XQuartz

What is XQuartz and why do I need to install it?

When you use the ssh command to access CSIL in a terminal window, essentially you are running all your software on CSIL in a terminal window on CSIL, and just connecting your Mac’s terminal window to the CSIL terminal window over the internet. That’s what the ssh command does.

This works just fine until you try to do something involving graphics, or windows, such as the idle3 program. On CSIL, idle3 brings up a window in the Linux windowing system, which is called X11. However, MacOS does not have the capability to display that kind of window built into it. You need an extra piece of software called an X11 Server—that’s exactly what XQuartz provides.

By installing XQuartz, and using the -X flag when you connect to CSIL with the ssh command, you allow your CSIL terminal window to open up graphics windows on your Mac for programs such as idle. If you don’t have a program like this in place, you get the NODISPLAY error message.

Where do I get it

Go to http://xquartz.org, and look for the link to download and install the latest version. Follow the instructions.

At the end, you will need to logout and log back in to your Mac session (not just your ssh session, but your entire MacOS session.) To do this, go to the Apple menu, i.e.  at upper left of your desktop where it says “Log Out Chris Gaucho” or whatever your name is. Log back in, and then try terminal again with the ssh -X ... command listed above.