Returning Printer-Specific Information
Important
The modern print platform is Windows' preferred means of communicating with printers. We recommend that you use Microsoft's IPP inbox class driver, along with Print Support Apps (PSA), to customize the print experience in Windows 10 and 11 for printer device development.
For more information, see Modern print platform and the Print support app design guide.
GDI sometimes requests a printer graphics DLL to return printer-specific information in between print jobs, by calling such DrvQuery-prefixed graphics DDI functions as DrvQueryAdvanceWidths (if defined by the graphics DLL).
An example of when this might occur is the case of a word processing application that is maintaining a WYSIWYG screen display of a printable page. To correctly display the line breaks in text, the word processor must base line-fitting calculations on character widths and other font metrics from the selected printer's implementation of a font.