Microsoft has enraged the developer community after a Redmond executive last week threatened a software developer to prevent him from demonstrating a Microsoft application running on Linux.

Whil Hentzen, of Milwaukee, Wisconsin, was to have presented a seminar showing how to run Microsoft's Visual FoxPro on Linux at the Bay Area Association of Database Developers last Wednesday.

But prior to the demonstration Hentzen received a call from a Microsoft marketing manager telling him that he would be in violation of the EULA (End User Licensing Agreement) for VFP if he demonstrated (or ran) the development tool on Linux.

After the brief conversation with Ken Levy, Microsoft's Visual FoxPro marketing manager, Hentzen decided to abandon the practical demonstration from his talk. Levy had contacted Hentzen after reading a paper on the subject, which Hentzen had edited.

The situation is confusing because Hentzen had done the demonstration before, with no problems. Also other developers had been led to believe from Microsoft that "as long as licenses were in order" running VFP on Linux as developer environment was permissible.

Hentzen has written to Microsoft asking for clarification to this conflicting advice. He told us this afternoon he was yet to receive a reply.

Hentzen wants to know firstly if developers can run VFP on a Linux as a developer environment, providing the appropriate license has been paid. He also wants to know the terms on which applications developed using VFP can be distributed.

The suggestion every Linux machine running VFP-created aps would need a VFP license. For Windows, only the development machine needs to have a VFP license.

"It appears that Microsoft is tying the tie its applications (developer tools) to their operating system," Hentzen told us.

"Given the legal difficulties that Microsoft has encountered over the years, we don't believe that this is legal, and thus we don't believe that this is the intent of the EULA," he added.

Microsoft is trying to get people to use Visual Basic, instead of FoxPro, because the former is a bigger money spinner for the company, Hentzen believes.

FoxPro is a database and development language purchased by Microsoft in 1992, and now known as Microsoft Visual FoxPro (VFP).

The technology allows developer to create an executable which can then be distributed (along with a support library dll) to an unlimited number of end users.

Reg reader Nick Causton tells us: "Within the FoxPro community there has been a lot of discussion recently about running VFP applications on Linux instead of Windows, no one seriously believed that Microsoft could prevent them from doing this."

Hentzen's demonstration follows on from work by other developers who have been able to get VFP to run on Linux using WINE.

"This now works quite well with the last few problems currently being addressed and there are now a number of people demonstrating this at seminars/conferences," he adds.

Developer Chet Gardiner, who attended the meeting, writes: "MS won't market it [VFP] for Windows applications, even those for which it's the best tool. Now M$ won't let us run it on any other OS, especially the one that's going to kick their butts."

"They are so interested in owning everyone's desktop that don't they see that in this way they could sell a whole lot of VFP stuff to other programmers and make some money out of it," he adds. ®