Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference

ID 767251
Date 6/24/2024
Public
Document Table of Contents

External Procedures

External procedures are user-written functions or subroutines. They are located outside of the main program and can't be part of any other program unit.

External procedures can be invoked by the main program or any procedure of an executable program.

External procedures can include internal subprograms (defining internal procedures). Internal subprograms are defined in the internal-subprogram-part that appears after a CONTAINS statement.

An external procedure can reference itself (directly or indirectly) if it has the RECURSIVE function attribute.

The interface of an external procedure is implicit unless an interface block is supplied for the procedure.