Michael,

FLL is a kind of DLL and you shouldn't have any problems with simultaneous use by several applications. Only program code and read-only data are shared by applications. Each process has its own copy of variables within FLL.

>Is my understanding correct that FLL is loaded only once ( when we issued
>Set library to certain.fll ) and the same copy in memory is used by several different applications.
>If FLL is not reentrant what should I do to avoid sharing ? Would having different names per application for FLL be enough to load it again for each application.