User`s guide

2-1
Printers, Print Jobs, and Queues for Systems Administrators
Chapter 2. Printers, Print Jobs, and Queues for System
Administrators
The printer subsystem includes a spooler, real printers, virtual printers, backends, and
queues. A print job can be sent to a printer attached directly to a local system, or it can be
sent over a network to a remote system and printed on a printer attached to the remote
system.
The system management tasks associated with printers include:
• Printing Processes , on page 2-1
• Print Spooler , on page 2-2
• Real and Virtual Printers , on page 2-3
• Local and Remote Printers, on page 2-3
• Printer Backends , on page 2-3
• Formatter Filters, on page 2-4
• Initial Printer Configuration, on page 2-7
• Spooler Overview, on page 3-1
• Spooler Troubleshooting, on page 5-1
Printing Processes
The system sends codes to the printer when you print a file. Some codes print specific
characters, such as a to z or 0 to 9. Other codes print characters or files, such as
underscoring certain characteristics or by adjusting the page length. Edit the file if you want
to send different character codes to the printer, such as to change the word that to this.
You do not have to understand the underlying codes.
To alter the way a printer works, you must understand what happens when you print a file,
which options you have for sending control information to the printer, and which printer
characteristics you can control.
You can use Web-based System Manager (wsm printers fast path), the System Manager
Interface Tool (SMIT), or the qprt command to send a file to a printer. You can also use
wsm printers or SMIT to cancel or prioritize a print job.
A file does not go directly to the printer. Web-based System Manager, SMIT, or the qprt
command calls the enq command and places the print request in a queue. The print request
stays in the queue until a printer becomes available, at which point, the qdaemon command
runs the (printer input/output backend) piobe command. The piobe command processes
the file and sends it, along with control information, to the printer. The printer receives a data
stream containing the contents of the file and the control information specified with the qprt
command.
Controlling the Printing Process
Add printer control information to the printer data stream in the following ways:
• Include printer control codes in the file.
Note: Set the print queue data stream to passthru (that is, d=p). Refer to ”Printer Colon
File Conventions” , on page 4-20 for more information.