Using A Fortran Interface to POSIX Threads

Pthreads is the library of POSIX standard functions for concurrent, multithreaded programming. The POSIX standard only defines an application programming interface (API) to the C programming language, not to Fortran. Many scientific and engineering applications are written in Fortran. Also, many of these applications exhibit functional, or tasklevel, concurrency. They would benefit from multithreading, especially on symmetric multiprocessors (SMP). We summarize here an interface to that part of the Pthreads library that is compatible with standard Fortran. The contribution consists of two primary source files: a Fortran module and a collection of C wrappers to Pthreads functions. The Fortran module defines the data structures, interface and initialization routines used to manage threads. The stability and portability of the Fortran API to Pthreads is demonstrated using common mathematical computations on three different systems.