Center for Computational Molecular Science and Technology Georgia Institute of Technology Center for Computational Molecular Science and Technology School of Chemistry and Biochemistry

CCMST Weekly News, April 13 2012

April 13, 2012 3:35 pm EDT

1. Announcements
2. Tip of the Week


Ggate Maintenance Under Way

Ggate is currently down for extraordinary maintenance. The system is now undergoing a full backup of the user data. Personnel from Penguin computing will be on site next Tuesday (04/17) to reinstall and upgrade the system. At this time ggate is expected to be back on line by the late afternoon of Friday 04/20.

Physical Chemistry Seminar Series

April 17, 2012 4:00 pm - 5:00 pm
MoSE 3201A
Prof. Christy Landes, Rice University
In Search of Concurrence between Biological and Synthetic Polymer Structure and Function

School Colloquim

April 19, 2012 4:00 pm - 5:00 pm
MoSE G011
Prof. Kyoung-Shin Choi, Purdue University
Materials Chemistry via Electrochemistry: Electrochemical Synthesis of Electrode Materials with Controlled Architectures for Use in Clean Energy Production


By Massimo

GNU screen

Another encore presentation of an old TOTW

This is a command I discovered only recently. Basically it is a screen manager for text terminals that allows you to share a terminal between several processes, typically interactive shells. It allows you to detach and reattach to interactive sessions as needed, and becomes very useful for remote use. For instance, it allows you to suspend a session on a remote machine, say fgate, then go home, login from home to fgate and resume the previous session. This is very useful in case you are running jobs using the interactive feature of PBS/Torque, as in this way it is possible to detach and reattach to the job without having to kill it.

Here is a quick and dirty tutorial for screen (type man screen for more help):

  • Start the screen command by typing screen. Now you are running an interactive shell controlled by Screen. The commands to screen are all prefixed by Ctrl-a.

Here are some of the screen commands:

  • Ctrl-a A (that is, type Ctrl-a followed by Shift-A) enter a name for the current window (useful if you have more than one)
  • Ctrl-a c Create a new window
  • Ctrl-a 0 switch to screen 0
  • Ctrl-a 1 switch to scrren 1 (and so on )
  • Ctrl-a d detach from the Screen session

Once you are detached, the screen session is still running, but it is not connected to a terminal. Now you can log off, then log on again (perhaps from another computer), and you can reattach to the screen session by typing:

  • screen -r.

To terminate screen, just terminate all the windows connected to the current screen session.


Do you have usage tips that you want to share with the other CCMST users? Please send them to Massimo ( for inclusion in the Tip of the Week section.