Visual Fortran provides support for creating multithread applications. You should consider using more than one thread if your application needs to manage multiple activities, such as simultaneous keyboard input and calculations. One thread can process keyboard input while a second thread performs data transformation calculations. A third thread can update the display screen based on data from the keyboard thread. At the same time, other threads can access disk files, or get data from a communications port.
When using Windows NT 4 or Windows 2000 on a multiprocessor machine (sometimes called an "SMP machine") you can achieve a substantial speedup on numerically intensive problems by dividing the work among different threads; the operating system will assign the different threads to different processors (symmetric multiprocessing or parallel execution). Even if you have a single-processor machine, multiple-window applications might benefit from multithreading because threads can be associated with different windows; one thread can be calculating while another is waiting for input.
While you might gain execution speed by having a program executed in multiple threads, there is overhead involved in managing the threads. You need to evaluate the requirements of your project to determine whether you should run it with more than one thread.
If your multithreaded code calls functions from the run-time library or does input/output, you must also link your code to the multithreaded version of the run-time libraries instead of the regular single-threaded ones. This is described in Compiling and Linking Multithread Programs and Building Programs and Libraries.
For additional resources about threads, processes, and multithreading, see Other Sources of Information.
For more information: