A module called DFMT.MOD is supplied with Visual Fortran. It contains interface statements to the underlying Win32 API routines as well as parameter and structure definitions used by the routines. You need to include a USE DFMT statement in the declarations section of every Fortran program unit (program, subroutine, function, or module) that uses multithread API routines.
The source code for the DFMT module (file name DFMT.F90) contains type definitions and external function declarations. You can use it as an added reference for the calling syntax, number, and type of arguments for a multithread procedure.
Other Windows APIs that support multithreading tasks (such as window management functions) are included in the DFWIN.F90 module, available to your programs with the USE DFWIN statement. For information about creating a Fortran Windows application, see Creating Windows Applications.