.\" 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.\" manual page may be incorrect or out-of-date.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
.\"     GNU texinfo documentation on glibc date/time functions.
.\" Modified Sat Jul 24 18:03:44 1993 by Rik Faith (faith@cs.unc.edu)
.\" Applied fix by Wolfgang Franke, aeb, 961011
.\" Corrected return value, aeb, 970307
.\" Added Single Unix Spec conversions and %z, aeb/esr, 990329.
.\" 2005-11-22 mtk, added Glibc Notes covering optional 'flag' and
.\"           'width' components of conversion specifications.
.\"
.\" Japanese Version Copyright (c) 2000 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated 2000-10-10, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated 2002-01-09, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2002-01-14, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2005-02-26, Akihiro MOTOKI
.\" Updated 2005-04-17, Akihiro MOTOKI
.\" Updated 2005-12-05, Akihiro MOTOKI, Catch up to LDP man-pages 2.16
.\"
.\"WORD:	conversion specifier	Ѵʸ
.\"WORD:	conversion specification	Ѵ
.\"WORD:	modifier		
.\"WORD:	broken-down time	̤()
.\"WORD:	Single Unix Specification	 Unix 
.\"
.TH STRFTIME 3  2005-11-23 "GNU" "Linux Programmer's Manual"
.SH ̾
strftime \- դӻʸؤѴ
.SH 
.nf
.B #include <time.h>
.sp
.BI "size_t strftime(char *" s ", size_t " max ", const char *" format ,
.BI "                const struct tm *" tm );
.fi
.SH 
.BR strftime ()
ؿ ϡ̤λ \fItm\fP Ƥ
\fIformat\fP ǻꤵ줿񼰻ˤäѴ
Ĺ \fImax\fP ʸ \fIs\fP ˽񤭹ࡣ
.PP
ʸ˴ޤޤ̾ʸѴ줺Τޤʸ \fIs\fP
˥ԡ롣Ѵפ '%' ʸǻϤޤꡢ
Ѵʸפǽü롣
ʲΤ褦Ѵ \fIs\fP ˳Ǽ:
.TP
.B %a
ߤΥˤξά̾
.TP
.B %A
ߤΥˤδ̾
.TP
.B %b
ߤΥˤξά̾
.TP
.B %B
ߤΥˤδ̾
.TP
.B %c
ߤΥˤưŪաɽ
.TP
.B %C
 (ǯξ 2 ) (SU)
.TP
.B %d
̻ (10 ʿɽ) (01-31)
.TP
.B %D
.B %m/%d/%y
(áꥫѤꥫʳιǤ
.B %d/%m/%y
Ūʶ路ΤǡѤ٤ǤϤʤ) (SU)
.TP
.B %e
.B %d
Ʊͤ˷̻ 10 ʿɽ뤬
1 ξ 10 ΰ̤˥֤ڡ֤(SU)
.TP
.B %E
̷Ѥݤνҡȡ (SU)
.TP
.B %F
.B %Y-%m-%d
 (ISO 8601 եեޥå) (C99)
.TP
.B %G
ISO 8601 ǯ ( 10 ʿɽ)
ISO 
.RB ( %V
򻲾) б 4 ǯ
ϴŪˤ
.B %y
ƱISO ǯǯˤʤ
ˤϤǯѤ롣(TZ)
.TP
.B %g
.B %G
Ʊ͡âޤޤ 2 Τߤɽ (00-99) (TZ)
.TP
.B %h
.B %b
 (SU)
.TP
.B %H
24 ɽǤλ (hour) (00-23)
.TP
.B %I
12 ɽǤλ (hour) (01-12)
.TP
.B %j
ǯνᤫ̻ (001-366)
.TP
.B %k
24 ɽǤλ (0-23)
1 ξˤ˥Ǥʤڡ֤롣
.RB ( %H
⻲) (TZ)
.TP
.B %l
12 ɽǤλ (0-12)
1 ξˤ˥Ǥʤڡ֤롣
.RB ( %I
⻲) (TZ)
.TP
.B %m
 (10 ʿɽ) (01-12)
.TP
.B %M
ʬ (10 ʿɽ) (00-59)
.TP
.B %n
ԡ (SU)
.TP
.B %O
̷Ѥݤνҡʲ򻲾ȡ(SU)
.TP
.B %p
ߤΥˤָסָפʸ
Ѹξˤ 'AM' ޤ 'PM' Ȥʤ롣
ϸ塢ϸȤư롣
.TP
.B %P
.B %p
ƱͤǤ뤬ʸѤ롣
Ѹξˤ 'am'  'pm' Ȥʤ롣(GNU)
.TP
.B %r
Ǥλ
POSIX Ǥ
.B "%I:%M:%S %p"
Ǥ롣(SU)
.TP
.B %R
24 ɽǤλäɽʤ
.RB ( %H:%M )
äޤΤϰʲ
.B %T
򻲾Ȥ뤳ȡ(SU)
.TP
.B %s
 (1970ǯ 1  1  00:00:00 UTC) ÿ (TZ)
.TP
.B %S
 (10 ʿɽ) (00-60)
(뱼äб뤿ᡢͤϰϤ 60 ޤǤȤʤäƤ)
.TP
.B %t
ʸ (SU)
.TP
.B %T
24 ɽλ (\fB%H:%M:%S\fP) (SU)
.TP
.B %u
βܤ (10 ʿɽ)  1 Ȥ (1-7)
.B %w
⻲ȡ(SU)
.TP
.B %U
ǯνᤫ̻ν (10 ʿɽ) (00-53)
ǯκǽ 1 λϤޤȤƷ׻롣
.B %V

.B %W
⻲Ȥ뤳ȡ
.TP
.B %V
ISO 8601:1988 ǤǯλϤᤫν (10 ʿɽ) (00-53)
ǯ˾ʤȤ 4 ʾޤޤǽν 1 ȤƷ׻롣
λϤޤϷȤ롣
.B %U

.B %W
⻲Ȥ뤳ȡ
.TP
.B %w
βܤ (10 ʿɽ)  0 Ȥ롣(0-6)
.B %u
⻲ȡ(SU)
.TP
.B %W
ǯνᤫ̻ν (10 ʿɽ) (00-53)
ǯκǽη 1 λϤޤȤƷ׻롣
.TP
.B %x
ߤΥǰŪɽϴޤޤʤ
.TP
.B %X
ߤΥǰŪʻɽդϴޤޤʤ
.TP
.B %y
β2 (ʬޤޤʤǯ) (00-99)
.TP
.B %Y
ʬޤ᤿ ( 4 ) ǯ
.TP
.B %z
ॾ GMT ؤΥեåȻ֡
RFC\ 822 ɬפǤ롣
("%a,\ %d\ %b\ %Y\ %H:%M:%S\ %z" ȤƻѤ)(GNU)
.TP
.B %Z
ॾޤϥ̾ޤϾά̾
.TP
.B %+
.\" Nov 05 -- Not in Linux/glibc, but is in some BSDs (according to
.\" their man pages)
.BR date (1)
Ǥ(TZ)
(glibc2 ǤϥݡȤƤʤ)
.TP
.B %%
'%' ʸ
.PP
ĤѴǤϡѴʸ
.B E

.B O
ֽҡפ֤Ȥˤä̽񼰤Ѥ褦˻ꤹ뤳ȤǤ롣
ߤΥˤ̽񼰤¸ߤʤˤϡ
̾Ѵ꤬Ѥ줿Τ褦ư (SU)
 UNIX  (Single Unix Specification) Ǥ
.BR %Ec ,
.BR %EC ,
.BR %Ex ,
.BR %EX ,
.BR %Ey ,
.BR %EY ,
.BR %Od ,
.BR %Oe ,
.BR %OH ,
.BR %OI ,
.BR %Om ,
.BR %OM ,
.BR %OS ,
.BR %Ou ,
.BR %OU ,
.BR %OV ,
.BR %Ow ,
.BR %OW ,
.BR %Oy ,
ˤĤƵҤ롣
.B O
Ҥ̷ο (޿Ȥ) ꤹ뤿˻Ѥ롣
.B E
Ҥϥ¸ɽꤹΤ˻Ѥ롣
(:
.B E
ҤܤǻѤƤ־¡סʿ
ʤɤθˤǯɽꤹ롣glibc 2.2 ʹߤǤΤͭ)
.PP
̤λﹽ¤ \fItm\fP ξܺ٤ \fI<time.h>\fP Ƥ롣
.BR ctime (3)
⻲Ȥ뤳ȡ
.SH ֤
.BR strftime ()
ؿʸ \fIs\fP ˳Ǽ줿ʸ֤
ʸ˽ü NULL ХȤϴޤޤʤ
ü NULL ХȤǼǤ礭äʸϤȡ
ʳξ 0 ֤ʸƤϽʤ
(libc 4.4.4 ʹߤǤεưŬѤƤ롣
libc 4.4.1 ʤɤ˸ŤС libc Ǥ
ʸû᤮ˤ \fImax\fP ֤롣)
.LP
֤ 0 ɬ⥨顼̣ƤǤϤʤΤդ뤳ȡ
㤨С¿ΥǤ
.B %p
϶ʸ֤
.SH Ķѿ
Ķѿ
.B TZ

.B LC_TIME
Ѥ롣
(:
.B LC_ALL
ꤵƤˤ
.B LC_TIME
⤽餬ͥ褵롣
.B LC_TIME

.B LC_ALL
ꤵƤʤˤ
.B LANG
Ѥ롣)
.SH 
SVr4, C89, C99.
ġѴ̩ˤɤεʤ˴ޤޤ뤫ϡ
ANSI C (ʤ) UNIX  (SU)Olson  timezone ѥå (TZ)
glibc ȼ (GNU) ǼƤ롣glibc2 Ǥ
.B %+
ϥݡȤƤʤ
ĤγĥԤƤ롣POSIX.1 Ǥ ANSI C Τߤ򻲾ȤƤ롣
POSIX.2 
.BR date (1)
ΤȤ˵ҤƤĤγĥ
.BR strftime ()
ˤŬѤǤ
.B %F
Ѵ C99  POSIX.1-2001 ˤ롣

SUSv2 Ǥϡ
.B %S
 00  61 ϰϤȤȵꤵƤ롣
ϡ1ʬ֤Τä 2ǽŪˤϤ뤳Ȥ
θƤΤΤǤ (ºݤˤϡΤ褦ʾϤޤǰ٤
äƤʤ)
.SH 
.SS glibc Ǥ
glibc ǤѴˤĤĥԤäƤ
(γĥ POSIX.1-2001 ˤϵꤵƤʤ
¾ΤĤΥƥƱͤεǽ󶡤Ƥ)
.\" HP-UX  Tru64 ˤƱͤεǽ롣
\&'%' ʸѴʸδ֤ˡץȤ
.I flag
ȥեɤ
.I 
Ǥ (ꤹˤ
.B E

.B O
Ҥ֤)

ʲΥե饰ʸѤǤ:
.TP
.B _
()
ͤηʸΥѥǥ () 򥹥ڡ (ʸ) ǹԤ
.TP
.B \-
(å)
ͤηʸФѥǥ󥰤Ԥʤ
.TP
.B 0
ѴʸǥեȤǤϥڡǥѥǥ󥰤ԤǤ⡢
ͤηʸؤΥѥǥ󥰤 0 ǹԤ
.TP
.B ^
ʸΥե٥åʸʸѴ롣
.TP
.B #
ʸʸʸؤ
(Υե饰ѴʸǤǽʤǤ
ͭѤʤΤ
.B %Z
ξǤ)
.PP
ץ10ʿҤϥե饰θ֤ȤǤ
(ե饰ϤʤƤ褤)եɤ礭ꤵ줿
硢ʸκ¦ϻꤵ줿ޤǥѥǥ󥰤롣
.SH Х
.BR gcc (1)
ΤĤΥСˤϤʤȤꡢ
.B %c
λˡˤĤưʲΤ褦ʷٹФ:
.I "warning: `%c' yields only last 2 digits of year in some locales"
.RI ( ٹ: ĤΥǤ `%c' ǯβ2夷Ϥʤ )
ץޤ
.B %c
ȤΤϤǤ뤳ȤǤ롣
.B %c
ȤŬڤդȻɽ뤳ȤǤ뤫Ǥ롣
.BR gcc (1)
Τ򤷤褦Ȥȡäꤷʤʬˤʤ
Ū줤ʲˡϰʲΤ褦ִؿɲä뤳ȤǤ롣
.in +4n
.nf

size_t
my_strftime(char *s, size_t max, const char *fmt,
            const struct tm *tm)
{
    return strftime(s, max, fmt, tm);
}
.fi
.in
.RE

ߤǤϡ
.BR gcc (1)
Ϥηٹޤ뤿 \fI\-Wno\-format\-y2k\fP ץ
󶡤Ƥꡢ嵭βϤϤɬפʤ
.SH 
ʲΥץȤ
.BR strftime ()
μ¸Ǥ롣
.nf

#include <time.h>
#include <stdio.h>
#include <stdlib.h>

int
main(int argc, char *argv[])
{
    char outstr[200];
    time_t t;
    struct tm *tmp;

    t = time(NULL);
    tmp = localtime(&t);
    if (tmp == NULL) {
        perror("localtime");
        exit(EXIT_FAILURE);
    }

    if (strftime(outstr, sizeof(outstr), argv[1], tmp) == 0) {
        fprintf(stderr, "strftime returned 0");
        exit(EXIT_FAILURE);
    }

    printf("Result string is \\"%s\\"\\n", outstr);
    exit(EXIT_SUCCESS);
} /* main */
.fi
.PP
ʲˡ
.BR strftime ()
 glibc ̤򤤤Ĥ:
.nf

$ ./a.out "%m"
Result string is "11"
$ ./a.out "%5m"
Result string is "00011"
$ ./a.out "%_5m"
Result string is "   11"
.fi
.SH Ϣ
.BR date (1),
.BR time (2),
.BR ctime (3),
.BR setlocale (3),
.BR sprintf (3),
.BR strptime (3)