J3/04-104

Date:    6 Dec 03
To:      J3
From:    Dan Nagle
Subject: C_Sizeof()


Many calls to C functions require a size argument.
Adding a c_sizeof() intrinsic to iso_c_binding
solves the problem.

Number:

Title: C_SIZEOF()

Submitted By: J3

Status: For Consideration

References: Section 15

Basic Functionality: Add c_sizeof() to iso_c_binding

Rationale:  Many calls to C functions require a size argument.
            Size in C is defined in terms of bytes, which are
            in turn defined in terms of characters.  Thus,
            the value returned depends on the C compiler, and
            may depend on the mode of the C compiler (which
            character set is default).

Estimated Impact: I estimate this feature to have low impact,
                  because compilers know the sizes of data items.

Detailed Specification: Many calls in C take the form
         of a starting address and a size,
         c_func( pointer-to-thingo, sizeof( thingo) );
         Being able to call these functions from within Fortran
         without having to write a C wrapper to supply
         the sizeof argument is helpful.

History: