Returns the height of the printable page in the internal units used by the printer driver or printing subsystem.
The printer-metrics-device-height function takes a printer-metrics object as its argument and returns the height of the printable page in the internal units used by the printer driver or printing subsystem of the printer. This function and printer-metrics-device-width should not be used to determine the aspect ratio of the printable page as some printers have size units that differ in the x and y directions.