All AUTOPACK names have the prefix ``AP_'', and all characters are capitals. Programs must not declare any symbols that begin with this prefix. Fortran PARAMETER definitions are provided in the file ``autopack.fh''.
The Fortran binding for a library function, if available, is documented in the function's description following the C synopsis. Functions that are present only in the Fortran interface appear in the function index in all caps.
In general, the Fortran versions of routines have the same name as the C routine, but with all letters capitalized. E.g. AP_INIT is the Fortran version of AP_init(). A Fortran routine generally has the same arguments as its C equivalent, but with value parameters being passed by reference as required by Fortran. If the C routine has a return value, the Fortran version will have an additional argument at the end of its parameter list, ``return_value'', through which the return value is passed back.
Difficulties arise because Fortran does not have the ability to deal with pointers. As a result, both sending and receiving introduce an additional memory-to-memory copy. Details are discussed in Sections 4.2 and 4.4.