Chapter 17. Printing

IN THIS CHAPTER

• How lpd, the Print Spooler, and the Print Queue Function in FreeBSD

• Kernel, Device, and Communications Mode Configuration

• Creating the Spool Directory and Setting Its Permissions

• Setting Up Text and Conversion Filters

• Configuring /etc/printcap to Control Print System Functions

• Enabling lpd for Command-Line Printing

• Basic Command-Line Printing

• Printing from X11 Applications

• Using the lpq Command to Check the Status of Print Jobs

• Removing Jobs from the Queue with the lprm Command

• Controlling Printers

• Basic Network Printing

• Next-Generation Printing with CUPS

• Troubleshooting

Setting up a printer in FreeBSD is one of the more complex topics you will have to deal with as an administrator. In the UNIX world, and particularly in FreeBSD, printing is not as simple as installing a driver, selecting the printer from a Control Panel, and then printing, as you might be accustomed. Printing from a FreeBSD system involves setting up one or more configuration files and possibly installing filters (small software programs, often merely shell scripts, that translate data files into printable code) if you need to print anything more advanced than plain text. After a basic outline of the major printing processes in FreeBSD, this chapter explains how to configure the kernel, device, and communications modes, create the spool directory, install printing filters, and enable printing for your users within X11 and at the command line. The chapter also covers the administration of network printing functions, and it provides troubleshooting guidance for identifying and resolving a number of common printing problems.

Although most printers sold today connect to the computer using USB, UNIX systems such as FreeBSD are still on shaky ground when it comes to supporting that now-ubiquitous standard. UNIX-style printing is geared primarily toward serial (RS-232) and parallel port printers, and this chapter will focus on the techniques used for connecting a printer using one of these methods (many printers are still sold with parallel interfaces as well as USB ones). If you have a USB printer that you want to get working with FreeBSD, the standard print spooler techniques might work for youbut if they don't, you might want to try CUPS, a next-generation UNIX printing system covered near the end of this chapter. (IrDA and Bluetooth printing is an even more dicey proposition; Bluetooth support in FreeBSD is brand-new and barely more than experimental in its level of advancement, and IrDA isn't supported at all.)

Note

GDI printers, sometimes also called WinPrinters, don't work with FreeBSD at all. These printers are usually cheaper than non-GDI printers because they move some of the printer control off of the hardware and into a software driver (in much the same way that so-called "soft modems" do). These printers have disadvantages: They use more system resources because the computer's CPU has to do much of the processing, rather than letting the printer do it, and they require special drivers that are usually available only for Windows. FreeBSD is only one of many operating systems unsupported by these printers.