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ctime

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asctime, ctime, gmtime, localtime, mktime, asctime_r, ctime_r, gmtime_r, localtime_r - ÆüÉդȻþ¹ï¤òÍ×ÁÇÊ̤λþ¹ï¤ä ASCII ¤ËÊÑ´¹¤¹¤ë

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#include <time.h>



char *asctime(const struct tm *tm);




char *asctime_r(const struct tm *tm, char *buf);



char *ctime(const time_t *timep);




char *ctime_r(const time_t *timep, char *buf);



struct tm *gmtime(const time_t *timep);




struct tm *gmtime_r(const time_t *timep, struct tm *result);



struct tm *localtime(const time_t *timep);




struct tm *localtime_r(const time_t *timep, struct tm *result);



time_t mktime(struct tm *tm);

ÀâÌÀ

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´Ø¿ô asctime() ¤È mktime() ¤Ï ǯ¡¦·î¡¦Æü¤Ê¤É¤ËʬΥ¤µ¤ì¤¿Í×ÁÇÊ̤λþ¹ï¤ò°ú¤­¿ô¤È¤¹¤ë¡£

Í×ÁÇÊ̤λþ¹ï¤Ï <time.h> ¤Ç°Ê²¼¤Î¤è¤¦¤ËÄêµÁ¤µ¤ì¤Æ¤¤¤ë tm ¹½Â¤ÂΤËÊÝ»ý¤µ¤ì¤ë¡£

struct tm {

    int tm_sec;         /* ÉÃ */

    int tm_min;         /* ʬ */

    int tm_hour;        /* »þ´Ö */

    int tm_mday;        /* Æü */

    int tm_mon;         /* ·î */

    int tm_year;        /* ǯ */

    int tm_wday;        /* ÍËÆü */

    int tm_yday;        /* ǯÆâÄÌ»»Æü */

    int tm_isdst;       /* ²Æ»þ´Ö */

};

tm ¹½Â¤ÂΤΥá¥ó¥Ð¡¼¤Ï°Ê²¼¤ÎÄ̤ê:

tm_sec

Éÿô¡¢¤Õ¤Ä¤¦¤Ï 0 ¤«¤é 59 ¤Þ¤Ç¤ÎÃÍ¡¢ ¤·¤«¤·±¼ÉäΤ¿¤á 60 ¤Þ¤Ç¤ÎÃͤϵö¤µ¤ì¤ë¡£

tm_min

ʬ¿ô¡¢0 ¤«¤é 59 ¤Þ¤Ç¤ÎÃÍ¡£

tm_hour

¿¿ÌëÃ椫¤é¤ÎÄÌ»»»þ´Ö¡¢0 ¤«¤é 23 ¤Þ¤Ç¤ÎÃÍ¡£

tm_mday

·î¤Ï¤¸¤á¤«¤é¤ÎÆü¿ô¡¢1 ¤«¤é 31 ¤Þ¤Ç¤ÎÃÍ¡£

tm_mon

1·î¤«¤é¤ÎÄÌ»»·î¿ô¡¢0 ¤«¤é 11 ¤Þ¤Ç¤ÎÃÍ¡£

tm_year

1900 ǯ¤«¤é¤ÎÄÌ»»Ç¯¿ô¡£

tm_wday

ÆüÍËÆü¤«¤é¤ÎÄÌ»»Æü¿ô(ÍËÆü)¡£0 ¤«¤é 6 ¤Þ¤Ç¤ÎÃÍ¡£

tm_yday

1 ·î 1 Æü¤«¤é¤ÎÄÌ»»Æü¿ô¡¢0 ¤«¤é 365 ¤Þ¤Ç¤ÎÃÍ¡£

tm_isdst

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ctime(t) ´Ø¿ô¤Ï¡¢ asctime(localtime(t)) ¤ÈÅù²Á¤Ç¤¢¤ë¡£ ¥«¥ì¥ó¥À¡¼»þ¹ï t ¤ò

"Wed Jun 30 21:49:08 1993\n"

¤È¤¤¤¦·Á¼°¤Îʸ»úÎó¤ØÊÑ´¹¤¹¤ë¡£ ÍËÆü¤Îά¾Î¤Ï `Sun', `Mon', `Tue', `Wed', `Thu', `Fri', `Sat' ¤Ç¤¢¤ë¡£ ·î¤Îά¾Î¤Ï `Jan', `Feb', `Mar', `Apr', `May', `Jun', `Jul', `Aug', `Sep', `Oct', `Nov', `Dec' ¤Ç¤¢¤ë¡£ ÊÖ¤êÃͤϡ¢ÀÅŪ (static) ¤Ë³ä¤êÅö¤Æ¤é¤ì¤¿Ê¸»úÎó¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£ ¤³¤Îʸ»úÎó¤Ï¡¢ÆüÉÕ¡¦»þ¹ï´Ø¿ô¤Î¤¤¤º¤ì¤«¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¤È¾å½ñ¤­¤µ¤ì¤ë¤³¤È¤¬¤¢¤ë¡£ ¤Þ¤¿¤³¤Î´Ø¿ô¤ÏÂç°èÊÑ¿ô tzname ¤Ë¸½ºß¤Î¥¿¥¤¥à¥¾¡¼¥ó¤Î¾ðÊó¤òÀßÄꤹ¤ë (tzset(3) »²¾È)¡£ ¥ê¥¨¥ó¥È¥é¥ó¥ÈÈǤǤ¢¤ë ctime_r() ¤âƱÍͤÀ¤¬¡¢ ʸ»úÎó¤Ï¥æ¡¼¥¶¡¼¤¬ÍÑ°Õ¤·¤¿¥Ð¥Ã¥Õ¥¡¤Ë³ÊǼ¤µ¤ì¤ë¡£¥Ð¥Ã¥Õ¥¡¤Î¥µ¥¤¥º¤Ï ¾¯¤Ê¤¯¤È¤â 26 ʸ»ú°Ê¾å¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£ ¤³¤Î´Ø¿ô¤Ï tzname ¤òÀßÄꤹ¤ëɬÍפϤʤ¤¡£

´Ø¿ô gmtime() ¤Ï¡¢¥«¥ì¥ó¥À¡¼»þ¹ï timep ¤ò ¶¨ÄêÀ¤³¦»þ (UTC) ¤Ç¤ÎÍ×ÁÇÊ̤λþ¹ï¤ØÊÑ´¹¤¹¤ë¡£ ǯ¤¬À°¿ô·¿¤Ë¼ý¤Þ¤é¤Ê¤¤¾ì¹ç¡¢NULL ¤òÊÖ¤¹¡£ ÊÖ¤êÃͤÏÀÅŪ¤Ë³ÎÊݤµ¤ì¤¿¹½Â¤ÂΤò»Ø¤·¤Æ¤ª¤ê¡¢¤³¤Î¸å¤Ç ÆüÉÕ¤ä»þ¹ï¤Ë´Ø¤¹¤ë´Ø¿ô¤Î¤¤¤º¤ì¤«¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¤È ¾å½ñ¤­¤µ¤ì¤ë²ÄǽÀ­¤¬¤¢¤ë¡£ gmtime_r() ¤âƱÍͤÀ¤¬¡¢ ¥Ç¡¼¥¿¤Ï¥æ¡¼¥¶¡¼¤¬ÍÑ°Õ¤·¤¿¹½Â¤ÂΤ˳ÊǼ¤µ¤ì¤ë¡£

´Ø¿ô localtime() ¤Ï¡¢¥æ¡¼¥¶¤¬»ØÄꤷ¤¿¥¿¥¤¥à¥¾¡¼¥ó¤Ç¤Î»þ¹ïÍ×ÁǤØÊÑ´¹¤¹¤ë¡£ ¤³¤Î´Ø¿ô¤Ï tzset(3) ¤ò¸Æ¤Ó½Ð¤·¤¿¤«¤Î¤è¤¦¤Ë¿¶Éñ¤¤¡¢ Âç°èÊÑ¿ô tzname ¤Ë¸½ºß¤Î¥¿¥¤¥à¥¾¡¼¥ó¤Î¾ðÊó¤òÀßÄꤹ¤ë¡£ ¤Þ¤¿¡¢timezone ¤Ë¶¨ÄêÀ¤³¦»þ (UTC) ¤È¥í¡¼¥«¥ëɸ½à»þ¤È¤Î »þº¹¤ÎÉÿô¤òÀßÄꤷ¡¢ °ìǯ¤Î°ìÉô¤Ç²Æ»þ´Ö¤¬Å¬ÍѤµ¤ì¤ë¾ì¹ç¤Ï daylight ¤Ë 0 ¤¬ÀßÄꤵ¤ì¤ë¡£ ÊÖ¤êÃͤÏÀÅŪ¤Ë³ÎÊݤµ¤ì¤¿¹½Â¤ÂΤò»Ø¤·¤Æ¤ª¤ê¡¢¤³¤Î¸å¤Ç ÆüÉÕ¤ä»þ¹ï¤Ë´Ø¤¹¤ë´Ø¿ô¤Î¤¤¤º¤ì¤«¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¤È ¾å½ñ¤­¤µ¤ì¤ë²ÄǽÀ­¤¬¤¢¤ë¡£ localtime_r() ¤âƱÍͤÀ¤¬¡¢ ¥Ç¡¼¥¿¤Ï¥æ¡¼¥¶¡¼¤¬ÍÑ°Õ¤·¤¿¹½Â¤ÂΤ˳ÊǼ¤µ¤ì¤ë¡£ tzname ¤òÀßÄꤹ¤ëɬÍפϤʤ¤¡£

´Ø¿ô asctime() ¤Ï¡¢Í×ÁÇÊ̤λþ¹ï tm ¤ò ctime() ¤ÈƱ¤¸·Á¼°¤Îʸ»úÎó¤ØÊÑ´¹¤¹¤ë¡£ ÊÖ¤êÃͤÏÀÅŪ¤Ë³ä¤êÅö¤Æ¤é¤ì¤¿Ê¸»úÎó¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£¤³¤Îʸ»úÎó¤Ï¡¢ ÆüÉÕ¡¦»þ¹ï´Ø¿ô¤Î¤¤¤º¤ì¤«¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¤È¾å½ñ¤­¤µ¤ì¤ë¤³¤È¤¬¤¢¤ë¡£ ¥ê¥¨¥ó¥È¥é¥ó¥ÈÈǤǤ¢¤ë asctime_r() ¤âƱÍͤÀ¤¬¡¢ ʸ»úÎó¤Ï¥æ¡¼¥¶¡¼¤¬ÍÑ°Õ¤·¤¿¥Ð¥Ã¥Õ¥¡¤Ë³ÊǼ¤µ¤ì¤ë¡£¥Ð¥Ã¥Õ¥¡¤Î¥µ¥¤¥º¤Ï ¾¯¤Ê¤¯¤È¤â 26 ʸ»ú°Ê¾å¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£

´Ø¿ô mktime() ¤Ï¡¢(¥í¡¼¥«¥ë¥¿¥¤¥à¤Çµ­½Ò¤µ¤ì¤Æ¤¤¤ë) Í×ÁÇÊ̤λþ¹ï¤ò ¥«¥ì¥ó¥À¡¼»þ¹ï¤ØÊÑ´¹¤¹¤ë¡£ ¤³¤Î´Ø¿ô¤Ï»þ¹ïÍ×ÁǤΤ¦¤Á tm_wday ¤È tm_yday ¤ÎÃͤÏ̵»ë¤·¡¢ ¾¤Î»þ¹ïÍ×ÁǤ«¤é¤½¤ì¤é¤ÎÃͤòºÆ·×»»¤¹¤ë¡£ ¹½Â¤ÂΤÎÍ×ÁǤ¬¤½¤ÎÀµ¤·¤¤ÈϰϤˤʤ¤¾ì¹ç¡¢Àµµ¬²½¤µ¤ì¤ë (¤Ä¤Þ¤ê¡¢10 ·î 40 Æü¤Ï 11 ·î 9 Æü¤ËÊѹ¹¤µ¤ì¤ë)¡£ ´Ø¿ô mktime() ¤ò¸Æ¤Ó½Ð¤¹¤È¡¢ Âç°èÊÑ¿ô tzname ¤¬¸½ºß¤Î¥¿¥¤¥à¥¾¡¼¥ó¤ËÀßÄꤵ¤ì¤ë¡£ Í×ÁÇÊ̤λþ¹ï¤ò¥«¥ì¥ó¥À¡¼»þ¹ï (µª¸µ¤«¤é¤ÎÉÿô) ¤Çɽ¸½¤Ç¤­¤Ê¤¤¾ì¹ç¡¢ mktime() ¤Ï (time_t)(-1) ¤òÊÖ¤·¡¢ »þ¹ïÍ×ÁÇ tm_wday ¤È tm_yday ¤ÏÊѹ¹¤·¤Ê¤¤¡£

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½àµò

POSIX.1-2001. C89 ¤È C99 ¤Ç¤Ï asctime(), ctime(), gmtime(), localtime(), mktime() ¤¬µ¬Äꤵ¤ì¤Æ¤¤¤ë¡£

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asctime(), ctime(), gmtime(), localtime() ¤Î 4 ¤Ä¤Î´Ø¿ô¤ÏÀÅŪ¥Ç¡¼¥¿¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¤Î¤Ç¡¢¥¹¥ì¥Ã¥É¥»¡¼¥Õ¤Ç¤Ï¤Ê¤¤¡£ ¤³¤ì¤é¤Î´Ø¿ô¤Î¥¹¥ì¥Ã¥É¥»¡¼¥ÕÈǤǤ¢¤ë asctime_r(), ctime_r(), gmtime_r(), localtime_r() ¤Ï SUSv2 ¤Çµ¬Äꤵ¤ì¤Æ¤ª¤ê¡¢ libc 5.2.5 °Ê¹ß¤ÇÍøÍѤǤ­¤ë¡£

glibc ¤ò´Þ¤à¿¤¯¤Î¼ÂÁõ¤Ç¤Ï¡¢ tm_mday ¤Ë 0 ¤ò»ØÄꤹ¤ë¤ÈÁ°·î¤ÎºÇ½ªÆü¤ò°ÕÌ£¤·¤Æ¤¤¤ë¤È²ò¼á¤µ¤ì¤ë¡£

glibc ¤Ç¤Ï¡¢ <time.h> ¤¬¥¤¥ó¥¯¥ë¡¼¥É¤µ¤ì¤ëÁ°¤Ë _BSD_SOURCE ¤¬ÄêµÁ¤µ¤ì¤ë¤È¡¢ struct tm ¤Ë°Ê²¼¤Î¥Õ¥£¡¼¥ë¥É¤¬Äɲ䵤ì¤ë¡£

long tm_gmtoff;           /* Seconds east of UTC */

const char *tm_zone;      /* Timezone abbreviation */

¤³¤ì¤Ï BSD ³ÈÄ¥¤Ç¤¢¤ê¡¢4.3BSD-Reno ¤«¤é¸½¤ì¤¿¡£

´ØÏ¢¹àÌÜ

date(1), gettimeofday(2), time(2), utime(2), clock(3), difftime(3), strftime(3), strptime(3), tzset(3), time(7)