Common Blocks

You can pass individual members of a Fortran common block in an argument list, just as you can any data item. However, you can also give a different language module access to the entire common block.

C or C++ modules can reference the items of a common block by first declaring a structure with fields that correspond to the common-block variables. Having defined a structure with the appropriate fields, the C or C++ module must then connect with the common block. The next two sections present methods for gaining access to common blocks.