Before I answer, I need to make it understood that working with FM projects, whether in a multi- or single modeler environment, really ought to be part of a strategy in which the projects are protected in a source control system. This ensures that access to the projects and the modifications to them are controlled and recorded.
It would be difficult to have read-only access to a FM project I think.
A brute force technique of making the directory where the model exists read-only would probably run into difficulties because files like log.xml (which has action log information), customdata.xml (diagram), session-log.xml, and upgradereport etc. write information there as things, such as moving things around in the diagram and adding, deleting, and modifying objects, are done.
You could make the model.xml file read-only but that could be changed by someone who knows about the concept of file attributes.
Assuming that you have your models in source control (and if you don't, consider the possibilities of sparing many tears by implementing it), you could give the person read access of some sort (it would depend on your source control system) so he could get a local copy of the project files. They would be writable but, because he would not have check-in rights, he could not introduce unwanted changes.
Another approach would be to make a copy of your actual project to a directory and periodically update it as changes are made to the real project, provided that the people given access to it know that it is just a playground and any changes they make will not make its way to the project. A email thread paper trail would be advisable.
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IAN HENDERSON
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