To add, remove and configure printers on platforms other than Motif use the system configuration utility. On Microsoft Windows this is the Printer Control Panel. On Cocoa printers are configured via the System Preferences.
A simple printing API is available via simple-print-port, which prints the contents of an output-pane to a printer.
The Hardcopy API also allows you to print plain text to a printer. To do this, use the functions print-text, print-file and print-editor-buffer, and the macro with-output-to-printer.
CAPI User Guide and Reference Manual (Unix version) - 25 Feb 2015