Windows 3.1 includes a set of standard print dialogs for use by Windows applications. These dialogs provide a standard interface for users to select and change printer settings, such as page range, number of copies, and print quality.
To support the standard print dialogs, a printer driver must export the ExtDeviceMode and DeviceCapabilities functions. The dialogs call these functions to get the necessary settings for the standard dialog boxes. If a printer driver does not export these functions, no printer settings can be set from within an application using the standard dialog. In such cases, the dialog boxes are displayed, but the printer settings fields are disabled (greyed out) and the driver is forced to use the system defaults that were previously set in Control Panel.
A printer driver can extend the capabilities of the standard print dialogs by exporting the AdvancedSetUpDialog function. If this function is available, the standard print dialogs display a More button. If the user chooses the button, the dialog box calls the AdvancedSetUpDialog function allowing the driver to display its own dialog box containing fields for advanced printer settings, such as color, duplex printing, and screen parameters.