Setting Up Text and Conversion Filters
Filters are where most of the actual work is done in printing. When lpd sends data to a filter, it sets the filter’s STDIN (standard input) to the file that is to be printed and its STDOUT to the printer device. Conversion filters are similar to text filters except they are designed to convert non-text file formats into a format the printer can understand.
Text Filters
As its name implies, the text filter is the filter lpd uses when it receives plain text to print. Because most printers will accept plain-text data without any need for special control information, the text filter can be as simple as a shell script that uses cat to simply pass the raw data to the printer, or it can be as complex as a program ...
Get FreeBSD6 Unleashed now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
