Execution Segments for Images

On each image, a segment is the sequence of statements executed before the first execution of an image control statement, between the execution of two image control statements, or after the last execution of an image control statement.

The segment executed immediately before the execution of an image control statement includes the evaluation of all expressions within that image control statement.

Main Program

A main program is a program unit whose first statement is not a SUBROUTINE, FUNCTION, MODULE, or BLOCK DATA statement. Program execution always begins with the first executable statement in the main program, so there must be exactly one main program unit in every executable program. For more information, see PROGRAM.

Intrinsic Modules

Intrinsic modules, like other module program units, contain specifications and definitions that can be made accessible to other program units. The intrinsic modules are part of the Fortran library.

An intrinsic module is specified in a USE statement, as follows:


The ISO_C_BINDING intrinsic module provides access to data entities that are useful in mixed-language programming. It takes the following form:


This intrinsic module provides access to the following data entities:

S’abonner à Fortran