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Red Hat® Linux 6 Unleashed

Chapter 16: Printing with Linux

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Chapter

Sections in this Chapter:

Printer
Devices

Linux
Printing Commands

Some Program
Tips

What Printer
Should I Use with Linux?

Simple
Formatting

Other
Helpful Programs

How Do I Print?

Other
Helpful Printer Programs and Filters

Troubleshooting
and More Information

The RHS
Linux Print System Manager

Infrared
Printer Support

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How Do I Print?

New Parallel-Port
Drivers

First, check to see that your printer is
plugged in, turned on, and attached to your computer's parallel port.
Pass-through parallel port cables shouldn't pose a problem, but don't
expect to be able to use your printer while you're using your CD-ROM,
QuickCam, SCSI adapter, or tape, ZIP, or SyQuest drive if attached to a
pass-through cable.For starters, try this simple
code:

# ls >/dev/lp0

Chances are your printer will activate and its print head will
move, but when you look at the printout, you might see a staircase effect, with
each word on a separate line, moving across the page. Don't worry--this is
normal and tells you that you can at least access your printer. Later in this
chapter, you'll find out how to fine-tune your
printing.

New Parallel-Port Drivers
Red Hat Linux 6.0
uses
version 2.2.5 of the Linux kernel. Unlike previous versions of the kernel, the
new 2.2.X and newer kernels use a new approach to parallel-port initialization,
recognition, and configuration. As distributed, Red Hat Linux 6.0 contains a
default kernel module configuration in
/etc/conf.modules. This line will enable the
low-level parallel-port parport kernel modules to attempt to autodetect any
attached printers:

alias parport_lowlevel parport_pc

You can view the output of these modules with the
dmesg
command following an attempt to
print. Look for output similar to this:

parport0: PC-style at 0x3bc [SPP,PS2]
parport0: no IEEE-1284 device present.
lp0: using parport0 (polling).

This shows that although an attached printer was not detected,
the computer's parallel port was detected. Any attached printer would use
/dev/lp0 as the printer device. You can also use the
lsmod
command to verify that the
printer drivers have been loaded following a print job like this:

# lsmod
Module Size Used by
parport_probe 2884 0 (autoclean)
parport_pc 5012 1 (autoclean)
lp 4412 0 (autoclean)
parport 7092 1 (autoclean) [parport_probe parport_pc lp]
...

The parport modules are
automatically loaded whenever the lp.o kernel module is used. If your parallel
port hardware is detected, you can examine the contents of the hardware file
under the printer port's device number (such as /dev/lp0) like
this:

# cat /proc/parport/0/hardware
base: 0x3bc
irq: none
dma: none
modes: SPP,PS2

You can also try the tunelp
command, which sets various
parameters to "tune" your printer port or lets you know if your
printer device is using interrupts or polling for printing. Try using this
code:

# tunelp /dev/lp0 -s

You might see this output:

/dev/lp0 status is 223, on-line

If tunelp reports "No
such device or address", or if you do not find an lp
character device, see Chapter 28, "Configuring and
Building Kernels." For details about the new parport drivers,
read the file parport.txt under the
/usr/doc/kernel-doc-2.2.5 directory.