Linux Certif

Toute la documentation sur la certification Linux LPI

fmemopen

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fmemopen, open_memstream - ¥á¥â¥ê¤ò¥¹¥È¥ê¡¼¥à¤È¤·¤Æ¥ª¡¼¥×¥ó¤¹¤ë

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#define _GNU_SOURCE
#include <stdio.h>

FILE *fmemopen(void *buf, size_t size, const char *mode);

FILE *open_memstream(char **ptr, size_t *sizeloc)

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buf ¤Ë NULL ¤¬»ØÄꤵ¤ì¤¿¾ì¹ç¡¢ fmemopen() ¤ÏưŪ¤Ë size ¥Ð¥¤¥È¤ÎŤµ¤Î¥Ð¥Ã¥Õ¥¡¤ò³ÎÊݤ¹¤ë¡£ ¤³¤ÎÊýË¡¤Ï¡¢°ì»þ¥Ð¥Ã¥Õ¥¡¤Ë¥Ç¡¼¥¿¤Î½ñ¤­¹þ¤ß¤ò¹Ô¤Ã¤Æ¤«¤é¡¢ ¤½¤ÎÆâÍƤòºÆÅÙÆɤ߽Ф¹¤è¤¦¤Ê¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¤ÇÍ­ÍѤǤ¢¤ë¡£ ¤³¤Î¥Ð¥Ã¥Õ¥¡¤Ï¥¹¥È¥ê¡¼¥à¤¬¥¯¥í¡¼¥º¤µ¤ì¤ë¤È¤­¤Ë¼«Æ°Åª¤Ë²òÊü¤µ¤ì¤ë¡£ ¸Æ¤Ó½Ð¤·¸µ¤«¤é¤Ï¤³¤Î´Ø¿ô¤¬³ä¤êÅö¤Æ¤¿°ì»þ¥Ð¥Ã¥Õ¥¡¤Ø¤Î¥Ý¥¤¥ó¥¿Ãͤò ÃΤëÊýË¡¤Ï¸ºß¤·¤Ê¤¤ÅÀ¤ËÃí°Õ (²¼µ­¤Î open_memstream() ¤â»²¾È)¡£

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$ ./a.out "1 23 43"

size=11; ptr=1 529 1849



#define _GNU_SOURCE

#include <assert.h>

#include <string.h>

#include <stdio.h>

#include <stdlib.h>



int

main(int argc, char *argv[])

{

    FILE *out, *in;

    int v, s;

    size_t size;

    char *ptr;



    assert(argc == 2);



    in = fmemopen(argv[1], strlen(argv[1]), "r");

    if (in == NULL) { perror("fmemopen"); exit(EXIT_FAILURE);}



    out = open_memstream(&ptr, &size);

    if (out == NULL) { perror("fmemopen"); exit(EXIT_FAILURE);}



    for (;;) {

        s = fscanf(in, "%d", &v);

        if (s <= 0)

            break;



        s = fprintf(out, "%d ", v * v);

        if (s == -1) { perror("fprintf"); exit(EXIT_FAILURE); }

    }

    fclose(in);

    fclose(out);

    printf("size=%ld; ptr=%s\n", (long) size, ptr);

    free(ptr);

    exit(EXIT_SUCCESS);

}

´ØÏ¢¹àÌÜ

open(3), feature_test_macros(7)