Printers and Printing

UMBC offers a variety of printing devices for generating hard copies of Unix files. Some printers are restricted to certain users or uses, whereas others are available to anyone with a Unix account and a file to print. Cost of page is $.10 a page for standard laser copy (single page or duplex).

In addition to the OIT printers, there are many other output devices on campus to which work may be sent. These are situated in various academic departments and have been installed there for the convenience of the faculty members there. As such, they are likely to be restricted to use by that department.

Using lpr

The general form of the Unix print command is lpr followed by a file name. As you will note, however, there are many options to this command which control both routing of print requests and formatting of various types of files.

Should you want to direct your printout to a particular printer, you will need to use an alternative form of the lpr command which encompasses the print queue name desired. The option -P must be used in all such cases; this option is followed by the queue name, and possibly is proceeded or followed by other controlling signals as well. (Examples below.) It is important to remember that there are no intervening spaces between -P and the print queue name.

Since there are now a great number of printers, and consequently a great number of queue names, on campus, it may be helpful to recognize that print queue names are derived from both the type and the location of the printer.

Some preliminary notes of caution: Never try to print files named core, a.out, or any executable file (generated by the cc -o or pc -o commands, among others). Also, please do not send files labeled ".gif" or other graphics files except for those in PostScript format. All of these are binary files and therefore are not printable. Attempting to do so will cause the printer to "hang," thus tying up the queue. Directory files are unprintable as well. Finally, no printer may be used as a photocopier---one copy only of each file, please. OIT is strict about enforcing this rule.

OIT Line Printers

OIT no longer uses line printer technology for academic work, and thus no such printers are available for Unix jobs. All printouts are generated via laser on 8 1/2 by 11-inch single sheets.

OIT Laser Printers

Office of Information Technology has now installed several new state-of- the-art laser postscript   printers for students in OIT's microcomputer labs, and by other campus networked machines. The new printers represent a major improvement over the older technology in terms of clarity, reliability and speed. Six hundred dots-per-inch resolution is now available, as is duplex, or double-sided, printing. The software interface to all of OIT's printers now also provides for load-balancing, so that the users need specify only a generic queue name and their jobs will be directed to the printer with the lightest current workload.

Departmental Printing Resources

Many of UMBC's academic departments have purchased laser printers for use by their faculty and graduate researchers. These machines function as general queues, reachable by anyone logged into one of the OIT Unix systems. Please note, however, that this does not mean that they are available for general use! If you a not a member of the owner department, you should seek permission before sending a job to its output device. If you are interested in a specific departmental printer, send mail to systems.

Managing Your Print Jobs

If your work entails printing a large number of files, you may find Unix's multi-option print commands somewhat cumbersome. Fortunately, Unix also provides various features to simplify your work sessions. This concept is known as "customizing your environment," and is described at some length in the section on that topic. One way of customizing your environment is to change your default printer by changing the PRINTER environment variable. For example:

When you reset this environment variable at the Unix system prompt, all lpr commands during your current session will have the effect described. If you work from different locations at different times, you might want to use this method as it easily allows you to define your printer based on your present location.

If, however, you always work from a single location, you can set your default printer automatically each time you log in. To do so, include the setenv PRINTER command in your .cshrc file. (If this is unfamiliar territory, see Customizing Your Environment.)

It is also possible to use Unix's alias command to redefine a Unix command, as in

Like environment variables, aliases can be set either at the system level, in which case they will apply during your current work session only, or at each login, upon execution of your .cshrc file.

Two other commands are handy for managing your print jobs, lpq and lprm: