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strtol

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strtol, strtoll, strtoq - ʸ»úÎó¤ò long int ¤ËÊÑ´¹¤¹¤ë

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#include <stdlib.h>



long int

strtol(const char *nptr, char **endptr, int base);



long long int

strtoll(const char *nptr, char **endptr, int base);

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endptr ¤¬¥Ì¥ëÃÍ (NULL) ¤Ç¤Ê¤¤¾ì¹ç¤Ï¡¢ºÇ½é¤Ë¸½¤ì¤¿ÉÔÀµ¤Êʸ»ú¤¬ strtol() ¤Ë¤è¤Ã¤Æ *endptr ¤ËÊݸ¤µ¤ì¤Æ¤¤¤ë¡£ ʸ»úÎó¤ËÍ­¸ú¤Ê¿ô»ú¤¬¤Ò¤È¤Ä¤â¤Ê¤±¤ì¤Ð¡¢ strtol() ¤Ï nptr ¤Î¸µ¤ÎÃͤò *endptr ¤ËÂåÆþ¤¹¤ë (¤½¤·¤Æ 0 ¤òÊÖ¤¹)¡£ Æäˡ¢*nptr ¤¬ `\0' °Ê³°¤Ç¡¢ÊÖ¤µ¤ì¤¿ **endptr ¤¬ `\0' ¤Ê¤é¤Ð¡¢Ê¸»úÎóÁ´ÂΤ¬Í­¸ú¤À¤Ã¤¿¤³¤È¤Ë¤Ê¤ë¡£

strtoll() ´Ø¿ô¤Ï strtol() ¤ÈƱÍͤÀ¤¬¡¢long long int ·¿¤ÎÃͤòÊÖ¤¹¡£

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EINVAL

(C99 ¤Ë¤Ï¤Ê¤¤) base ¤¬Âбþ¤·¤Æ¤¤¤Ê¤¤ÃͤǤ¢¤ë¡£

ERANGE

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strtol() ¤Ï SVr4, 4.3BSD, C89, C99 ¤È POSIX.1-2001 ¤Ë½àµò¤·¤Æ¤¤¤ë¡£ strtoll() ¤Ï C99 ¤È POSIX.1-2001 ¤Ë½àµò¤·¤Æ¤¤¤ë¡£

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"C" °Ê³°¤Î¥í¥±¡¼¥ë¤Î¾ì¹ç¡¢¤½¤Î¾¤Îʸ»úÎó¤â¼õ¤±ÉÕ¤±¤é¤ì¤ë¤«¤â¤·¤ì¤Ê¤¤¡£ (Î㤨¤Ð¡¢¸½ºß¤Î¥í¥±¡¼¥ë¤Î 1000 Ëè¤Î¶èÀÚ¤êʸ»ú¤¬¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤ë¤«¤â¤·¤ì¤Ê¤¤¡£)

BSD ¤Ë¤Ï¡¢

quad_t

strtoq(const char *nptr, char **endptr, int base);

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°Ê²¼¤Î¥×¥í¥°¥é¥à¤Ï strtol() ¤Î»ÈÍÑÎã¤Ç¤¢¤ë¡£ ºÇ½é¤Î¥³¥Þ¥ó¥É¥é¥¤¥ó°ú¤­¿ô¤Ë¤Ï strtol() ¤¬¿ô»ú¤È¤·¤Æ²ò¼á¤¹¤ëʸ»úÎó¤ò»ØÄꤹ¤ë¡£ (¾Êά²Äǽ¤Ê) ÆóÈÖÌܤΰú¤­¿ô¤Ë¤Ï ÊÑ´¹¤Ë»ÈÍѤµ¤ì¤ë´ð¿ô¤ò»ØÄꤹ¤ë (¤³¤Î°ú¤­¿ô¤Ï atoi(3) ¤ò»È¤Ã¤Æ¿ôÃͤËÊÑ´¹¤µ¤ì¤ë¡£ atoi(3) ¤Ï strtol() ¤è¤ê¤â´Êñ¤Ê¥¤¥ó¥¿¥Õ¥§¡¼¥¹¤ò»ý¤Ä´Ø¿ô¤Ç¡¢ ¤½¤ÎÃæ¤Ç¤Ï¥¨¥é¡¼¥Á¥§¥Ã¥¯¤Ï¹Ô¤ï¤ì¤Ê¤¤)¡£ ¤³¤Î¥×¥í¥°¥é¥à¤Î¼Â¹ÔÎã¤ò¤¤¤¯¤Ä¤«°Ê²¼¤Ë¼¨¤¹:

$ ./a.out 123

strtol() returned 123

$ ./a.out '    123'

strtol() returned 123

$ ./a.out 123abc

strtol() returned 123

Further characters after number: abc

$ ./a.out 123abc 55

strtol: Invalid argument

$ ./a.out ''

No digits were found

$ ./a.out 4000000000

strtol: Numerical result out of range

¥×¥í¥°¥é¥à¤Î¥½¡¼¥¹¥³¡¼¥É¤Ï°Ê²¼¤ÎÄ̤ê:

#include <stdlib.h>

#include <limits.h>

#include <stdio.h>

#include <errno.h>



int

main(int argc, char *argv[])

{

    int base;

    char *endptr, *str;

    long val;



    if (argc < 2) {

        fprintf(stderr, "Usage: %s str [base]\n", argv[0]);

        exit(EXIT_FAILURE);

    }



    str = argv[1];

    base = (argc > 2) ? atoi(argv[2]) : 10;



    errno = 0;    /* To distinguish success/failure after call */

    val = strtol(str, &endptr, base);



    /* Check for various possible errors */



    if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))

            || (errno != 0 && val == 0)) {

        perror("strtol");

        exit(EXIT_FAILURE);

    }



    if (endptr == str) {

        fprintf(stderr, "No digits were found\n");

        exit(EXIT_FAILURE);

    }



    /* If we got here, strtol() successfully parsed a number */



    printf("strtol() returned %ld\n", val);



    if (*endptr != '\0')        /* Not necessarily an error... */

        printf("Further characters after number: %s\n", endptr);



    exit(EXIT_SUCCESS);

}

´ØÏ¢¹àÌÜ

atof(3), atoi(3), atol(3), strtod(3), strtoul(3)