EN JA
OFFSETOF(3)
OFFSETOF(3) FreeBSD Library Functions Manual OFFSETOF(3)

NAME

offsetofoffset of a structure member

SYNOPSIS

#include < stddef.h>

size_t
offsetof( type, member);

DESCRIPTION

The offsetof() macro expands to an integer constant expression of type size_t and yields the offset, in bytes, of the field member from the start of the structure type.

A compiler error will result if member is not aligned to a byte boundary (i.e. it is a bit-field).

STANDARDS

The offsetof() macro conforms to ANSI X3.159-1989 (“ANSI C89”).
February 18, 2010 FreeBSD