System Administration Guide
Chapter 4, Managing printers and print jobs

About the print service

About the print service

The UNIX system print service is a collection of utilities that help you, as system administrator (or lp administrator), to configure, monitor, and control the printers on your system. See Figure 4-1, ``Overview of print request processing''.

The print service:

When a user sends a file to a printer, the print service assigns the request (or ``print job'') a unique name, the ``request ID''. The request ID consists of the name of the printer on which the file is to be printed and a unique number identifying the file. Use this request ID to find out the status of the print job or to cancel the print job. See ``Deleting print jobs'' and ``Viewing jobs in the print queue''. The print service keeps track of all the print requests in the request log. 

The print job is ``spooled'', or lined up, with other print jobs to be sent to a printer. Each print job is processed and waits its turn in line to be printed. This line of pending print jobs is called a ``print queue''. Each printer has its own queue; you can hold jobs in the queue, move jobs up in a queue, or transfer jobs to another queue.