Printer backend programming
The printer backend is a standard feature of the base operating system.
The base operating system printer backend receives and processes print requests from a spooler, usually the qdaemon command. The printer backend is implemented by the piobe command
The printer backend supports all of the printers installed in the Object Data Manager (ODM) Predefined database. You can customize the printer backend to assist in the administration of the printing subsystem. For more information, see Printing administration. You can also modify the printer backend to add unsupported printers and National Language Support (NLS) code page translation tables.
Adding a printer to the printer backend involves adding a printer colon file for that printer. In many cases, the printer colon file of a similar printer can be duplicated with little modification. If modification of an existing printer colon file is not sufficient, you can write a print formatter. If the modifications exceed the scope of the print formatter, you may need to write a new printer backend.
See the following sections for more information:
- Adding a printer using the printer colon file provides a procedure for duplicating a printer colon file.
- Printer colon file escape sequences provides information useful in modifying a printer colon file.
- Back-end routines in libqb and Backend and qdaemon interaction can assist you in writing a new printer backend.
The procedure for translating NLS code points in the print file to code points for the printers varies depending upon whether the code sets are single-byte or multibyte. For more information, see:
Third-party vendors may want to customize the printer backend for special purposes.