AppleInsider reports that users experimenting with various settings in Mac OS X 10.6.5 have discovered a way to bring the iOS AirPrint function back to your Mac. AirPrint uses CUPS technology, an open source Unix-friendly printing architecture, owned and maintained by Apple.
The CUPS filter used to convert the AirPrint URF format into PDF format for printing was the component removed from the public release of 10.6.5, despite being available for testing in beta versions of the update.
So how do you get AirPrint capabilities back?
First, you need to restore the URF-to-PDF filter currently missing from 10.6.5. You need to get that from a beta version of Mac OS X 10.6.5 that included it. Next, you must overwrite two CUPS MIME files:
- apple.types: "includes a definition of the image/urf MIME type for CUPS, which is used when advertising a shared printer's features over Bonjour."
- apple.convs: "specifies that print jobs of the image/urf MIME type should use the urftopdf filter."
Delete all your network printers (System Preferences > Print & Fax) and reboot your Mac. Turn on Printer Sharing on your Mac and your iOS 4.2 device should read the available printers, thanks to Bonjour advertising.