CUPS, an acronym for Common Unix Printing System, is a printing system for Unix-like operating systems such as Linux and Darwin (OS X).
A computer running CUPS is a host that can accept print jobs from client computers, process them, and send them to the appropriate printers queue.
Printing via CUPS allows the usage of the Internet printing protocol, or ipp and has the following advantages:
Most of your interaction with CUPS will be when you print something. CUPS and many users of Unix-like systems refer to the act of pressing the Print button as “submitting a print job”.
Most of the time print jobs are sent to a printers queue and the printer prints them one after the other.
Printing to a McGill uPrint printer with the ACELab printer card can only be done from the command line.
First check to see if the printers are available on your machine:
me@ace-ws-00:~$ lpstat -p
printer HP-color-laserjet is idle. enabled since Thu 26 Jan 2017 02:32:24 PM EST printer McGill_Color is idle. enabled since Thu 16 Feb 2017 02:43:59 PM EST printer mcgill_mono is idle. enabled since Thu 16 Feb 2017 02:44:14 PM EST printer mcgill_mono_beta is idle. enabled since Thu 16 Feb 2017 02:44:00 PM EST
You can see here a local printer and the McGill uPrint printers.
To print a file named myfile.txt to mcgill_mono using the amni16 “Evans Lab Students” account:
me@ace-ws-00:~$ lp -U amni16 -d mcgill_mono myfile.txt request id is mcgill_mono-117 (1 file(s))
Then, find the amni16 uPrint card and release the job at the printer.
* You need to be using your MCIN user name and password to sign on to your system. * Alternativly, your user must be a member of the local or LDAP enabled lpadmin group.
Start the printers interface from the command line with sudo as follows:
Then choose Forward
Occasionally a job will be held and when a held job reaches the top of the print queue it is held and all of the jobs after it are also held until the held job is cancelled, moved or deleted.
1. Go to the CUPS web interface ( Make sure to include the :631 after the name of the workstation hosting the printer or you will not get the CUPS web interface )
2. Choose the Jobs tab and you will see all of the print requests (Jobs)
3. In this example the first job is held which stops the printer queue. This prevents all of the print jobs after it from printing. Choose the most approriate option from the following:
* Choose Cancel Job to cancel the print job and remove it from the job (or print) queue. * Choose Release Job in order to print the held job or * Choose Move if you want to move this to a different printer queue.
In the example below the document has been held in the queue since June 9th so I would probably choose the Cancel Job button.
Do not print a test page at this time. Double-click on the printer, select Policies and change Operation Policy from Default Behavior to Authenticated and click Apply.