Novell LINUX ENTERPRISE DESKTOP 10 SP2 - DEPLOYMENT GUIDE 08-05-2008 Deployment Manual page 477

To delete the print job on the server, use a command such as lpstat -h
cups.example.com -o to determine the job number on the server, provided the
server has not already completed the print job (that is, sent it completely to the printer).
Using this job number, the print job on the server can be deleted:
cancel -h cups.example.com queue-jobnnumber
20.9.8 Defective Print Jobs and Data
Transfer Errors
Print jobs remain in the queues and printing resumes if you switch the printer off and
on or shut down and reboot the computer during the printing process. Defective print
jobs must be removed from the queue with cancel.
If a print job is defective or an error occurs in the communication between the host and
the printer, the printer prints numerous sheets of paper with unintelligible characters,
because it is unable to process the data correctly. To deal with this, follow these steps:
1 To stop printing, remove all paper from ink jet printers or open the paper trays
of laser printers. High-quality printers have a button for canceling the current
printout.
2 The print job may still be in the queue, because jobs are only removed after they
are sent completely to the printer. Use lpstat -o or lpstat -h
cups.example.com -o to check which queue is currently printing. Delete
the print job with cancel queue-jobnumber or cancel -h
cups.example.com queue-jobnumber.
3 Some data may still be transferred to the printer even though the print job has
been deleted from the queue. Check if a CUPS back-end process is still running
for the respective queue and terminate it. For example, for a printer connected
to the parallel port, the command fuser -k /dev/lp0 can be used to termi-
nate all processes that are still accessing the printer (more precisely: the parallel
port).
4 Reset the printer completely by switching it off for some time. Then insert the
paper and turn on the printer.
Printer Operation 461