In labtest mode, students start with an empty home directory. The optional unsubmit component of labtest enables faculty to provide students with access to previously submitted content which can be used for reference or a starting point for a test.

To enable unsubmit, please follow these four steps:

1) Check to ensure that the permission of your course submit directory allows access by anyone in group submit:

% ls -ald /eecs/course/9999/submit
drwxr-xr-x 10 bob faculty 4096 Sep  3 23:31 /eecs/course/9999/submit

This submit directory is owned by user bob, group faculty, and allows “r-x” for other, hence anyone in group submit would be able to access this directory.

2) Check to ensure that the permission of any assignment subdirectories in the submit directory for which you wish to allow unsubmit are readable and executable by the submit group:

% ls -ald /eecs/course/9999/submit/a1 /eecs/course/9999/submit/a2
drwxr-x--- 107 bob submit  4096 Sep 14 11:30 /eecs/course/9999/submit/a1
drwxr-x---  38 bob submit  4096 Sep 19 12:10 /eecs/course/9999/submit/a2

Both a1 and a2 are group submit, and r-x.

3) Create a file called “unsubmit” in each of the submit assignment subdirectories in the submit directory for which you wish to allow unsubmit:

% touch /eecs/course/9999/submit/a1/unsubmit /eecs/course/9999/submit/a2/unsubmit

4) Ensure that the unsubmit files created above are readable by everyone:

% chmod 644 /eecs/course/9999/submit/a1/unsubmit /eecs/course/9999/submit/a2/unsubmit

That's it! Unsubmit is now setup. However, please continue reading this document for other important details about unsubmit.

When a student logs in during a labtest for which unsubmit has been enabled, the student will see an “unsubmit” directory in his home directory containing his previously submitted work. For example:

% ls
unsubmit
% cd unsubmit
% ls
A1 A2
% cd A1
% ls
a1.java

It is important to note that the contents of the unsubmit directory are READ ONLY. If a student wishes to modify previously submitted work, he must copy it out of the unsubmit directory. For example:

% cp unsubmit/A1/a1.java ~/newa1.java
% jedit ~/newa1.java

If the student tries to modify the copy of a1.java in the unsubmit directory, he will get “permission denied” errors.

• Submit data is copied from submit directories to a local unsubmit cache before students get the “Your machine will be rebooted in 5 minutes” message, just prior to their test. Anything that students submit after the reboot warning will not be available in the unsubmit cache without additional intervention by you (see below). As a result, students must be made aware that they should submit anything that they expect to be able to unsubmit 10 minutes prior to the beginning of the test.
• The contents of your submit directory must be readable by the group “submit” including the “unsubmit” file. Failure to set the correct permissions on all files before your test begins will mean that your students will not be able to unsubmit without additional work by you (see next point).
• If you do not setup your unsubmit directory properly, or you forgot to remind your students to submit their data 10 minutes prior to the test, you can refresh the unsubmit cache by logging in to https://webapp.cse.yorku.ca/pcmode (from a machine not in labtest mode), and click the “Refresh Unsubmit Cache” button at the bottom of the screen. Students will need to log out and back in to have the local copy of their unsubmit cached refreshed.
• The “unsubmit” directory that students see when they login is READ ONLY. If students wish to make changes, they need to copy the data out, and modify it accordingly.
• Only text files will be unsubmittable. Any other files (eg. .class, .jar) will not be copied to the users unsubmit directory.