Computer Science Lab FAQ
This page comprises of a list of Frequently Asked Questions that students have asked. If you have questions that you think should be included here, please mail them to csmath.ilt@whitman.edu
Additional detailed information concerning operations in the labs can be found via the Computer Science Lab Manual.
File locking typically is a safety mechanism to ensure a file can be written to and read from by multiple processes. Google Chrome typically makes a file lock as a symbolic link to the process ID on a specific workstation host. If that link resolves to a process, then a new instance of Google Chrome does not get opened. However, the symbolic link may not have been properly written or removed on logout or shutdown.
Here's how to fix that.
Terminal Fix:
A simple command to delete this lock file will do the trick:
rm /home/$USER/.config/google-chrome/SingletonLock
The $USER variable will be expanded to be the username of the user who executed the command.
File Manager Fix:
Alternatively, a user can use the file manager to navigate to /home/$USER/.config/google-chrome/ and remove the SingletonLock file.
Firefox will notify a user if it believes there is another session open on a different computer. This may be the case if the previous session did not terminate gracefully. File locking typically is a safety mechanism to ensure a file can be written to and read from by multiple processes, but it seems to have caused you some headache!
The popup that Firefox will show may have the text "Firefox is already running, but is not responding. To use Firefox, you must first close the existing Firefox process, restart your device, or use a different profile."
Terminal Fix
The files to delete are located within the user's profile directory /home/$USER/.mozilla/firefox/*.default/ where * is a fuzzy match for Firefox's profile hash. The specific files to delete are lock and .parentlock. This one line command should remove those files:
rm /home/$USER/.mozilla/firefox/*.default*/lock
Alternately, if the prior command doesn't work, one can try to delete all files in a user's home directory that contain the string ending with 'lock' with the following command:
find ~ -type f -name "*[l|L]ock" -delete
File manager fix
In your preferred file manager, you are able to navigate to the directory which holds the lock on Firefox in /home/$USER/.mozilla/firefox/*.default/ Since it is difficult to know what the user profile's hash is; whether they are using a default profile versus a custom profile, it is recommended to go to each folder that has default or default-release appended.
There are many ways to accomplish this task. The recommended method is to us an sftp application such as WinSCP (Windows), FileZilla (Windows, Mac, Linux), or Cyberduck (Win, Mac, Linux). One can also use one of the terminal commands: scp, rsync, or sftp. Then you may copy files to and from your account. See the Computer Science Lab Manual for more detailed instructions.
On-campus, you are able to use an SSH client to connect directly to the lab computers. The Domain Name Services server will resolve any of the hostnames taped onto the computer to the computer's respective ip address (such as kleene, pneuli, and aphrodite). Please refer to the Math & CS Lab Manual: Lab Map with Hostnames.
You can verify if you are the only person connected to the computer with the who or w commands
The Linux Labs are standardized with the same authentication provider as myWhitman. In other words, your Whitman login and password are the same.
If you know your password and would like to change it, the fastest method would be to use myWhitman's Password Changing tool at: https://my.whitman.edu/whitman-password
If you forget your password you can get a new one by going to the WCTS Helpdesk in the Technology Services building with your Whitman ID card. They will change your password to one randomly selected by the system.
If you are off campus, you will have to contact the Helpdesk at 509-527-4976 or by email at helpdesk@whitman.edu.