If you want to print PDF files, you would normally open them individually with a PDF viewer such as Okular or Atril and start printing from there. For starters, this takes up some of your valuable time, and there is a risk of overlooking and omitting some files. Compared to this, printing at the command line often only involves a single line of input if you are working with specific file formats, more specifically Postscript and PDF.

Printing with lpr

You can use the lp and lpr commands to print one or multiple files. The calls are the same for sending a print command to the default printer: lp FILE and lpr FILE. If you want to output the job to a specific device, you need to pass in the job name using the -d parameter (for lp) or -P (for lpr). A call via a pipe also works: echo "Hi!" | lpr or echo "Hi!" | lp put your output directly onto paper. You can request multiple printouts by stipulating -n NUMBER (for lp) or -# NUMBER (for lpr).

A print job for multiple files in a single command combines the pages into a single print job for both lp and lpr. This can cause problems in the case of printer malfunctions, for example, if the printer breaks down and pages are swallowed up due to a paper jam. Besides this, you only see the name of the last file to be printed in alphabetic order in the print job query. Although the lpq command displays the complete queue, this can also lead to problems in practical terms if you have large-scale combined print jobs. It takes some effort to identify a file that has not been printed due to a printer error and to start a reprint. Starting the jobs individually offers you a better overview. A small for construct (Listing 1) helps here. Figure 1 illustrates the difference between the two methods of starting print jobs.

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