The interface displays the function calling convention, namely arguments and their type along with intended usage in the routine (either IN, OUT, or INOUT) in Fortran-90 form. An argument marked as IN indicates it was referenced in the routine. If marked as OUT, the argument was set somewhere in the routine. An intent of INOUT indicates the argument was both referenced and set. In addition to the function call frame, a comment (denoted by '*' in column 1) is generated to display the function's location (specifically filename plus starting and ending line number). If the function sets any common members, or if FORTRAN I/O is performed in the routine, additional comments will be displayed denoting appropriate function side effects occurring there. If the FUNCTION or SUBROUTINE statement is immediately followed by comments, the first two comments containing any alphanumeric characters will also be displayed in the function interface (denoted by a 'C' in column 1) to serve as programmer documentation for the function.
Comments generated in the interface regarding common and external I/O use in the routine are normally somewhat cryptic. A more verbose form of both comments can be enabled with the "V=i" option, although extensive usage in the routine will lead to very long comments.
Commons used in the routine are reported with their label followed by 'S' if any member is set, and by 'R' if any member is referenced. The verbose form displays "Set" and "Refd". I/O performed in the routine is reported by the unit number (or variable) followed by square braces, [ ], enclosing letters representing the I/O statements involving the unit. The meaning of the compact (and verbose) I/O notation is given below.
I/O Interface Comment Notation Compact Verbose Statement Referenced B Bksp BACKSPACE C Clos CLOSE E Endf ENDFILE I Inqu INQUIRE O Open OPEN R Read READ r rew REWIND W Write WRITE or PRINT