Goals for this Hour

In this hour, you learn how to

• Find local printers with printers

• Send a print job to a printer with lpr or lp

• Format print jobs with pr

• Work with the print queue by using lpq, lprm

Various techniques can minimize the complexity of printing in UNIX, the best of which is to create an alias called print that has all the default configuration information you want. If you define PRINTER as an environment variable, most of the UNIX print utilities will default to the printer you specify as the value of the PRINTER environment variable, for example, when searching print queues for jobs. The queue, or list, is where all print jobs are placed for processing by the specific printer.

The differing "philosophies" of BSD and System V have caused problems in the area of printing. In a nutshell, because UNIX systems are almost always networked (that is, hooked together with high-speed data-communications lines), the most valuable feature of a printing tool would be allowing the user to choose to print on any of the many printers attached. For this to work, each machine with an attached printer must be listening for requests from other machines. The root of the BSD versus System V problem is that the two listen for different requests. A System V machine can't send a print job to a printer attached to a BSD machine, and vice versa.