offsetof

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Version: 2006-05-23 (openSuse - 09/10/07)

Section: 3 (Bibliothèques de fonctions)

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offsetof - ¹½Â¤ÂΤΥá¥ó¥Ð¡¼¤Î¥ª¥Õ¥»¥Ã¥È¤òÊÖ¤¹

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#include <stddef.h>

size_t offsetof(type, member);

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C89, C99, POSIX.1-2001.

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    $ ./a.out
    offsets: i=0; c=4; d=8 a=16
    sizeof(struct s)=16


#include <stddef.h>

#include <stdio.h>

#include <stdlib.h>



int

main(void)

{

    struct s {

        int i;

        char c;

        double d;

        char a[];

    };



    /* ½ÐÎϤϥ³¥ó¥Ñ¥¤¥é°Í¸¤Ç¤¢¤ë */



    printf("offsets: i=%ld; c=%ld; d=%ld a=%ld\n",

            (long) offsetof(struct s, i),

            (long) offsetof(struct s, c),

            (long) offsetof(struct s, d),

            (long) offsetof(struct s, a));

    printf("sizeof(struct s)=%ld\n", (long) sizeof(struct s));



    exit(EXIT_SUCCESS);

}