.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one.
.\" 
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\" 
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\"
.\" References consulted:
.\"     Linux libc source code
.\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
.\"     386BSD man pages
.\" Modified Sat Jul 24 19:49:27 1993 by Rik Faith (faith@cs.unc.edu)
.\" Modified Fri Apr 26 12:38:55 MET DST 1996 by Martin Schulze (joey@linux.de)
.\" Modified 2001-11-13, aeb
.\" Modified 2004-11-16, mtk
.\"
.\" Japanese Version Copyright (c) 1997 Hiroaki Nagoya
.\"         all rights reserved.
.\" Translated 1997-02-10, Hiroaki Nagoya <nagoya@is.titech.ac.jp>
.\" Updated 1999-09-01, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2001-10-15, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2001-12-13, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2002-01-03, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2005-02-24, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.\"WORD: Coordinated Univarsal Time  
.\"WORD: broken-down time  ̤λ
.\"
.TH CTIME 3  2004-11-16 "" "Linux Programmer's Manual"
.SH ̾
asctime, ctime, gmtime, localtime, mktime, asctime_r, ctime_r, gmtime_r,
localtime_r \- դȻ̤λ ASCII Ѵ
.SH 
.nf
.B #include <time.h>
.sp
.BI "char *asctime(const struct tm *" tm );
.br
.BI "char *asctime_r(const struct tm *" tm ", char *" buf );
.sp
.BI "char *ctime(const time_t *" timep );
.br
.BI "char *ctime_r(const time_t *" timep ", char *" buf );
.sp
.BI "struct tm *gmtime(const time_t *" timep );
.br
.BI "struct tm *gmtime_r(const time_t *" timep ", struct tm *" result );
.sp
.BI "struct tm *localtime(const time_t *" timep );
.br
.BI "struct tm *localtime_r(const time_t *" timep ", struct tm *" result );
.sp
.BI "time_t mktime(struct tm *" tm );
.fi
.SH 
ؿ \fBctime()\fP, \fBgmtime()\fP, \fBlocaltime()\fP 
\fItime_t\fP ΥˤȤ롣
ϡ (UTC) 1970 ǯ 1  1  00:00:00
ηвÿȲᤵ롣
.PP
ؿ \fBasctime()\fP  \fBmktime()\fP 
ǯʤɤʬΥ줿̤λȤ롣
.PP
̤λ \fI<time.h>\fP ǰʲΤ褦Ƥ
\fItm\fP ¤Τݻ롣
.sp
.RS
.nf
.ne 11
.ta 8n 16n 32n
struct tm {
        int     tm_sec;                 /*  */
        int     tm_min;                 /* ʬ */
        int     tm_hour;                /*  */
        int     tm_mday;                /*  */
        int     tm_mon;                 /*  */
        int     tm_year;                /* ǯ */
        int     tm_wday;                /*  */
        int     tm_yday;                /* ǯ̻ */
        int     tm_isdst;               /* ƻ */
};
.ta
.fi
.RE
.PP
\fItm\fP ¤ΤΥСϰʲ̤:
.TP
.I tm_sec
.\" motoki ():  (leap second)  2 뤳ȤϤʤΤǡ
.\"                60 θȻפ롣
ÿդĤ 0  59 ޤǤ͡
äΤ 60 ޤǤͤϵ롣
.TP
.I tm_min
ʬ0  59 ޤǤ͡
.TP
.I tm_hour
椫̻֡0  23 ޤǤ͡
.TP
.I tm_mday
Ϥᤫ1  31 ޤǤ͡
.TP
.I tm_mon
1̻0  11 ޤǤ͡
.TP
.I tm_year
1900 ǯ̻ǯ
.TP
.I tm_wday
̻()0  6 ޤǤ͡
.TP
.I tm_yday
1  1 ̻0  365 ޤǤ͡
.TP
.I tm_isdst
ƻ֤ͭɤΥե饰
ͤʤвƻ֤ͭˤʤꡢ0 ʤ̵ͤʤФξˤ
̣ʤ
.PP
.BI ctime( t )
ؿϡ
.BI asctime(localtime( t ))
Ǥ롣
 \fIt\fP 
.sp
.RS
"Wed Jun 30 21:49:08 1993\\n"
.RE
.sp
ȤʸѴ롣
άΤ
`Sun', `Mon', `Tue', `Wed', `Thu', `Fri', `Sat' Ǥ롣
άΤ `Jan', `Feb', `Mar', `Apr', `May', `Jun', `Jul', `Aug',
`Sep', `Oct', `Nov', `Dec' Ǥ롣
֤ͤϡŪ (static) ˳Ƥ줿ʸؤΥݥ󥿤Ǥ롣
ʸϡաؿΤ줫ƤӽФȾ񤭤뤳Ȥ롣
ޤδؿѿ \fItzname\fP ˸ߤΥॾξꤹ
.RB ( tzset (3)
)
ꥨȥǤǤ \fBctime_r()\fP Ʊͤ
ʸϥ桼ѰդХåե˳Ǽ롣ХåեΥ
ʤȤ 26 ʸʾǤʤФʤʤ
δؿ \fItzname\fP ꤹɬפϤʤ
.PP
ؿ \fBgmtime()\fP ϡ \fItimep\fP 
 (UTC) Ǥ̤λѴ롣
ǯ˼ޤʤ硢NULL ֤
֤ͤŪ˳ݤ줿¤ΤؤƤꡢθ
դ˴ؤؿΤ줫ƤӽФ
񤭤ǽ롣
\fBgmtime_r()\fP Ʊͤ
ǡϥ桼Ѱդ¤Τ˳Ǽ롣
.PP
ؿ \fBlocaltime()\fP ϡ桼ꤷॾǤλǤѴ롣
δؿ
.BR tzset (3)
ƤӽФΤ褦˿񤤡
ѿ \fItzname\fP ˸ߤΥॾξꤹ롣
ޤ\fItimezone\fP ˶ (UTC) ȥɸȤ
ÿꤷ
ǯΰDzƻ֤ŬѤ \fIdaylight\fP  0 ꤵ롣
֤ͤŪ˳ݤ줿¤ΤؤƤꡢθ
դ˴ؤؿΤ줫ƤӽФ
񤭤ǽ롣
\fBlocaltime_r()\fP Ʊͤ
ǡϥ桼Ѱդ¤Τ˳Ǽ롣
\fItzname\fP ꤹɬפϤʤ
.PP
ؿ \fBasctime()\fP ϡ̤λ \fItm\fP 
\fBctime()\fP ƱʸѴ롣
֤ͤŪ˳Ƥ줿ʸؤΥݥ󥿤Ǥ롣ʸϡ
աؿΤ줫ƤӽФȾ񤭤뤳Ȥ롣
ꥨȥǤǤ \fBasctime_r()\fP Ʊͤ
ʸϥ桼ѰդХåե˳Ǽ롣ХåեΥ
ʤȤ 26 ʸʾǤʤФʤʤ
.PP
ؿ \fBmktime()\fP ϡ(륿ǵҤƤ) ̤λ
Ѵ롣
δؿϻǤΤ \fItm_wday\fP  \fItm_yday\fP ̵ͤ뤷
¾λǤ餽ͤƷ׻롣
¤ΤǤϰϤˤʤ硢
(Ĥޤꡢ10  40  11  9 ѹ)
ؿ \fBmktime()\fP ƤӽФȡ
ѿ \fItzname\fP ߤΥॾꤵ롣
̤λ򥫥 (ÿ) ɽǤʤ硢
\fBmktime()\fP  (time_t)(-1) ֤
 \fItm_wday\fP  \fItm_yday\fP ѹʤ
.SH ֤
ƴؿϤ줾Ҥ֤ͤ顼ξ NULL
(\fBmktime()\fP Ǥ \-1) ֤
.SH 
.BR asctime() ,
.BR ctime() ,
.BR gmtime() ,
.B localtime()
 4 ĤδؿŪǡؤΥݥ󥿤֤ΤǡåɥդǤϤʤ
δؿΥåɥǤǤ
.BR asctime_r() ,
.BR ctime_r() ,
.BR gmtime_r() ,
.B localtime_r()
 SUSv2 ǵꤵƤꡢ
libc 5.2.5 ʹߤѤǤ롣
.LP
.I glibc
ޤ¿μǤϡ
.I tm_mday
 0 ꤹκǽ̣ƤȲᤵ롣
.LP
glibc Ǥϡ
.I <time.h>
󥯥롼ɤ _BSD_SOURCE ȡ
struct tm ˰ʲΥեɤɲä롣
.sp
.RS
.nf
long tm_gmtoff;           /* Seconds east of UTC */
const char *tm_zone;      /* Timezone abbreviation */
.fi
.RE
.sp
 BSD ĥǤꡢ4.3BSD-Reno 鸽줿
.SH 
SVID 3, POSIX, BSD 4.3, ISO 9899
.SH Ϣ
.BR date (1),
.BR gettimeofday (2),
.BR time (2),
.BR utime (2),
.BR clock (3),
.BR difftime (3),
.BR newctime (3),
.BR strftime (3),
.BR strptime (3),
.BR tzset (3)