Microsoft offers Longhorn OS preview

Microsoft will reveal more details of Longhorn, its next version of Windows, at its Professional Developers Conference next...

Microsoft will reveal more details of Longhorn, its next version of Windows, at its Professional Developers Conference next month, although anyone wanting to see more of the user interface, codenamed Aero, will have to wait.

Aero may make a cameo appearance in Microsoft chairman Bill Gates' opening keynote, but is not finished yet and is unlikely to be included in the pre-beta release of Longhorn whichwill be handed out to PDC attendees.

Perhaps more important to developers is that Microsoft will give PDC attendees the scoop on Avalon, the little talked-about engine underlying the Longhorn user interface.

Microsoft has described the technology as "a brand new client platform for building smart, connected, media-rich applications in Longhorn". Developers at the show will be told how to take advantage of Avalon in their applications.

Thanks to Avalon, Longhorn will support new styles of user interfaces and user interface elements. Developers will be able to create Windows client applications using the type of navigation features found on the web to browse through information.

Another key topic at PDC will be Windows Future Storage (WinFS), a service that sits on top of the existing Windows file system and is meant to make it simpler and more intuitive for users to find files on computers running Longhorn.

WinFS uses technology from the Yukon release of Microsoft's SQL Server database, which is expected to ship late next year.

Microsoft's PDC documentation describes WinFS as an "entirely new user experience and model around the storage of user's data". For example, Outlook address book data today is restricted to that e-mail client. With WinFS, that data could be made available to all applications on a PC.

However, applications will have to be rewritten to take advantage of such capabilities. Microsoft will release a slew of application upgrades at around the time Longhorn is released.

Jupiter Research senior analyst Joe Wilcox sees WinFS as the PDC headliner because of the impact a new storage system is likely to have on developers and businesses.

"Microsoft at PDC needs to show some significant development progress on the new file system coming for Yukon and Longhorn. Developers and businesses will need some time to prepare new applications and, possibly, retrofit old ones to support the new file system."

A lot of work remains to be done on WinFS. It works, and developers can start developing applications for it, but it is slow, fragile and many features are missing, a source familiar with the development said.

Microsoft is working hard to finish the PDC version of Longhorn. The goal is to meet "zero bug bounce", a stage where development catches up to testing and there are no active bugs, at least for the moment.

The operating system will be "about half done" when the PDC rolls around, the source said. A Longhorn beta is planned for next year.

Gates has said that Longhorn is "a big bet" for Microsoft and that this next major release of Windows is "a bit scary" because Microsoft is making some fundamental changes to its PC software. Several thousand developers at Microsoft are working on the product.

Other code-named products and technologies on the PDC agenda are Indigo and Whidbey.

Indigo is Microsoft's new framework and programming model for building connected applications and web services. Whidbey is the next version of Microsoft's developer tool Visual Studio .net.

PDC takes place in Los Angeles and runs from 26 to 30 October.

Joris Evers writes for IDG News Service

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