Use an “event” — a synchronization object that allows one thread to notify another that an event has occurred. Events are useful when a thread needs to know when to perform its task. For example, a thread that copies data to a data archive would need to be notified when new data is available. Look for CreateEvent(), SetEvent(), WaitForSingleObject(), etc.

Thanks Joaquin, What is the include file for the 2nd suggestion. I get undeclared for identifiers upin compile with it. The fortran function is going to be reading alot of data continously and then reducing the data with some large fortran routines already existing. From there it will pass through the C file to a Java GUI for display. There will be option to change the read rate and other calculations that I thought would make this possible with multi threading. The alternative was to have a thread in the Java GUI continuosly looping and calling the fortran through c wrapper but I thought there were possible time delay issues there. Let me know if you have any thoughts on this? Thanks for the help. Ken

Thanks Joaquin.

Thanks all. The include windows.h cleaned up many errors.

Yes Joaquin. I am using MS VC 5.0. The library was built using Compaq Visual Fortran 6.0 Not sure what is the SP? Are there any work arounds? Thanks