зеркало из https://github.com/github/ruby.git
908 строки
22 KiB
C
908 строки
22 KiB
C
/*
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* strftime.c
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*
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* Public-domain implementation of ANSI C library routine.
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*
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* It's written in old-style C for maximal portability.
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* However, since I'm used to prototypes, I've included them too.
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*
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* If you want stuff in the System V ascftime routine, add the SYSV_EXT define.
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* For extensions from SunOS, add SUNOS_EXT.
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* For stuff needed to implement the P1003.2 date command, add POSIX2_DATE.
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* For VMS dates, add VMS_EXT.
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* For a an RFC822 time format, add MAILHEADER_EXT.
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* For ISO week years, add ISO_DATE_EXT.
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* For complete POSIX semantics, add POSIX_SEMANTICS.
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*
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* The code for %c, %x, and %X now follows the 1003.2 specification for
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* the POSIX locale.
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* This version ignores LOCALE information.
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* It also doesn't worry about multi-byte characters.
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* So there.
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*
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* This file is also shipped with GAWK (GNU Awk), gawk specific bits of
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* code are included if GAWK is defined.
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*
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* Arnold Robbins
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* January, February, March, 1991
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* Updated March, April 1992
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* Updated April, 1993
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* Updated February, 1994
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* Updated May, 1994
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* Updated January, 1995
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* Updated September, 1995
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* Updated January, 1996
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*
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* Fixes from ado@elsie.nci.nih.gov
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* February 1991, May 1992
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* Fixes from Tor Lillqvist tml@tik.vtt.fi
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* May, 1993
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* Further fixes from ado@elsie.nci.nih.gov
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* February 1994
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* %z code from chip@chinacat.unicom.com
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* Applied September 1995
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* %V code fixed (again) and %G, %g added,
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* January 1996
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*/
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#include "config.h"
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#ifndef GAWK
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#include <stdio.h>
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#include <ctype.h>
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#include <string.h>
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#include <time.h>
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#endif
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#if defined(TM_IN_SYS_TIME) || !defined(GAWK) && !defined(_WIN32_WCE)
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#include <sys/types.h>
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#include <sys/time.h>
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#endif
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/* defaults: season to taste */
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#define SYSV_EXT 1 /* stuff in System V ascftime routine */
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#define SUNOS_EXT 1 /* stuff in SunOS strftime routine */
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#define POSIX2_DATE 1 /* stuff in Posix 1003.2 date command */
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#define VMS_EXT 1 /* include %v for VMS date format */
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#define MAILHEADER_EXT 1 /* add %z for HHMM format */
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#define ISO_DATE_EXT 1 /* %G and %g for year of ISO week */
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#ifndef GAWK
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#define POSIX_SEMANTICS 1 /* call tzset() if TZ changes */
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#endif
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#if defined(ISO_DATE_EXT)
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#if ! defined(POSIX2_DATE)
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#define POSIX2_DATE 1
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#endif
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#endif
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#if defined(POSIX2_DATE)
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#if ! defined(SYSV_EXT)
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#define SYSV_EXT 1
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#endif
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#if ! defined(SUNOS_EXT)
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#define SUNOS_EXT 1
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#endif
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#endif
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#if defined(POSIX2_DATE)
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#define adddecl(stuff) stuff
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#else
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#define adddecl(stuff)
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#endif
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#undef strchr /* avoid AIX weirdness */
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#ifndef __STDC__
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#define const /**/
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extern void tzset();
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static int weeknumber();
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adddecl(static int iso8601wknum();)
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#else
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extern void tzset(void);
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static int weeknumber(const struct tm *timeptr, int firstweekday);
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adddecl(static int iso8601wknum(const struct tm *timeptr);)
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#endif
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#ifdef STDC_HEADERS
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#include <stdlib.h>
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#include <string.h>
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#else
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extern void *malloc();
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extern void *realloc();
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extern char *getenv();
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extern char *strchr();
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#endif
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#define range(low, item, hi) max(low, min(item, hi))
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#if !defined(OS2) && !defined(MSDOS) && defined(HAVE_TZNAME)
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extern char *tzname[2];
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extern int daylight;
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#ifdef SOLARIS
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extern long timezone, altzone;
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#else
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#ifdef __hpux
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extern long timezone;
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#else
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extern int timezone, altzone;
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#endif
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#endif
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#endif
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#undef min /* just in case */
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/* min --- return minimum of two numbers */
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#ifndef __STDC__
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static inline int
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min(a, b)
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int a, b;
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#else
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static inline int
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min(int a, int b)
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#endif
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{
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return (a < b ? a : b);
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}
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#undef max /* also, just in case */
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/* max --- return maximum of two numbers */
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#ifndef __STDC__
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static inline int
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max(a, b)
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int a, b;
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#else
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static inline int
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max(int a, int b)
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#endif
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{
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return (a > b ? a : b);
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}
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/* strftime --- produce formatted time */
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#ifndef __STDC__
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size_t
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strftime(s, maxsize, format, timeptr)
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char *s;
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size_t maxsize;
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const char *format;
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const struct tm *timeptr;
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#else
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size_t
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strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
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#endif
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{
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char *endp = s + maxsize;
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char *start = s;
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auto char tbuf[100];
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long off;
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int i, w;
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long y;
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static short first = 1;
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#ifdef POSIX_SEMANTICS
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static char *savetz = NULL;
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static int savetzlen = 0;
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char *tz;
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#endif /* POSIX_SEMANTICS */
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#ifndef HAVE_TM_ZONE
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#ifndef HAVE_TM_NAME
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#ifndef HAVE_TZNAME
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extern char *timezone();
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struct timeval tv;
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struct timezone zone;
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#else
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#ifdef __hpux
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struct timeval tv;
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struct timezone zone;
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#endif
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#endif /* HAVE_TZNAME */
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#endif /* HAVE_TM_NAME */
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#endif /* HAVE_TM_ZONE */
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/* various tables, useful in North America */
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static const char *days_a[] = {
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"Sun", "Mon", "Tue", "Wed",
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"Thu", "Fri", "Sat",
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};
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static const char *days_l[] = {
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"Sunday", "Monday", "Tuesday", "Wednesday",
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"Thursday", "Friday", "Saturday",
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};
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static const char *months_a[] = {
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"Jan", "Feb", "Mar", "Apr", "May", "Jun",
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"Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
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};
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static const char *months_l[] = {
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"January", "February", "March", "April",
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"May", "June", "July", "August", "September",
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"October", "November", "December",
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};
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static const char *ampm[] = { "AM", "PM", };
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if (s == NULL || format == NULL || timeptr == NULL || maxsize == 0)
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return 0;
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/* quick check if we even need to bother */
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if (strchr(format, '%') == NULL && strlen(format) + 1 >= maxsize)
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return 0;
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#ifndef POSIX_SEMANTICS
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if (first) {
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tzset();
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first = 0;
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}
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#else /* POSIX_SEMANTICS */
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tz = getenv("TZ");
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if (first) {
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if (tz != NULL) {
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int tzlen = strlen(tz);
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savetz = (char *) malloc(tzlen + 1);
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if (savetz != NULL) {
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savetzlen = tzlen + 1;
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strcpy(savetz, tz);
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}
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}
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tzset();
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first = 0;
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}
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/* if we have a saved TZ, and it is different, recapture and reset */
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if (tz && savetz && (tz[0] != savetz[0] || strcmp(tz, savetz) != 0)) {
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i = strlen(tz) + 1;
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if (i > savetzlen) {
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savetz = (char *) realloc(savetz, i);
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if (savetz) {
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savetzlen = i;
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strcpy(savetz, tz);
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}
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} else
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strcpy(savetz, tz);
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tzset();
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}
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#endif /* POSIX_SEMANTICS */
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for (; *format && s < endp - 1; format++) {
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tbuf[0] = '\0';
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if (*format != '%') {
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*s++ = *format;
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continue;
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}
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again:
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switch (*++format) {
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case '\0':
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*s++ = '%';
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goto out;
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case '%':
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*s++ = '%';
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continue;
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case 'a': /* abbreviated weekday name */
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if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6)
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strcpy(tbuf, "?");
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else
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strcpy(tbuf, days_a[timeptr->tm_wday]);
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break;
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case 'A': /* full weekday name */
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if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6)
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strcpy(tbuf, "?");
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else
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strcpy(tbuf, days_l[timeptr->tm_wday]);
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break;
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#ifdef SYSV_EXT
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case 'h': /* abbreviated month name */
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#endif
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case 'b': /* abbreviated month name */
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if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11)
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strcpy(tbuf, "?");
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else
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strcpy(tbuf, months_a[timeptr->tm_mon]);
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break;
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case 'B': /* full month name */
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if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11)
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strcpy(tbuf, "?");
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else
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strcpy(tbuf, months_l[timeptr->tm_mon]);
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break;
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case 'c': /* appropriate date and time representation */
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strftime(tbuf, sizeof tbuf, "%a %b %e %H:%M:%S %Y", timeptr);
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break;
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case 'd': /* day of the month, 01 - 31 */
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i = range(1, timeptr->tm_mday, 31);
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sprintf(tbuf, "%02d", i);
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break;
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case 'H': /* hour, 24-hour clock, 00 - 23 */
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i = range(0, timeptr->tm_hour, 23);
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sprintf(tbuf, "%02d", i);
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break;
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case 'I': /* hour, 12-hour clock, 01 - 12 */
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i = range(0, timeptr->tm_hour, 23);
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if (i == 0)
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i = 12;
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else if (i > 12)
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i -= 12;
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sprintf(tbuf, "%02d", i);
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break;
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case 'j': /* day of the year, 001 - 366 */
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sprintf(tbuf, "%03d", timeptr->tm_yday + 1);
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break;
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case 'm': /* month, 01 - 12 */
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i = range(0, timeptr->tm_mon, 11);
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sprintf(tbuf, "%02d", i + 1);
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break;
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case 'M': /* minute, 00 - 59 */
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i = range(0, timeptr->tm_min, 59);
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sprintf(tbuf, "%02d", i);
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break;
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case 'p': /* am or pm based on 12-hour clock */
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i = range(0, timeptr->tm_hour, 23);
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if (i < 12)
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strcpy(tbuf, ampm[0]);
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else
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strcpy(tbuf, ampm[1]);
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break;
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case 'S': /* second, 00 - 60 */
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i = range(0, timeptr->tm_sec, 60);
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sprintf(tbuf, "%02d", i);
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break;
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case 'U': /* week of year, Sunday is first day of week */
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sprintf(tbuf, "%02d", weeknumber(timeptr, 0));
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break;
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case 'w': /* weekday, Sunday == 0, 0 - 6 */
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i = range(0, timeptr->tm_wday, 6);
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sprintf(tbuf, "%d", i);
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break;
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case 'W': /* week of year, Monday is first day of week */
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sprintf(tbuf, "%02d", weeknumber(timeptr, 1));
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break;
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case 'x': /* appropriate date representation */
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strftime(tbuf, sizeof tbuf, "%m/%d/%y", timeptr);
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break;
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case 'X': /* appropriate time representation */
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strftime(tbuf, sizeof tbuf, "%H:%M:%S", timeptr);
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break;
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case 'y': /* year without a century, 00 - 99 */
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i = timeptr->tm_year % 100;
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sprintf(tbuf, "%02d", i);
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break;
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case 'Y': /* year with century */
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sprintf(tbuf, "%ld", 1900L + timeptr->tm_year);
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break;
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#ifdef MAILHEADER_EXT
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/*
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* From: Chip Rosenthal <chip@chinacat.unicom.com>
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* Date: Sun, 19 Mar 1995 00:33:29 -0600 (CST)
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*
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* Warning: the %z [code] is implemented by inspecting the
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* timezone name conditional compile settings, and
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* inferring a method to get timezone offsets. I've tried
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* this code on a couple of machines, but I don't doubt
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* there is some system out there that won't like it.
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* Maybe the easiest thing to do would be to bracket this
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* with an #ifdef that can turn it off. The %z feature
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* would be an admittedly obscure one that most folks can
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* live without, but it would be a great help to those of
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* us that muck around with various message processors.
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*/
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case 'z': /* time zone offset east of GMT e.g. -0600 */
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#ifdef HAVE_TM_NAME
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/*
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* Systems with tm_name probably have tm_tzadj as
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* secs west of GMT. Convert to mins east of GMT.
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*/
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off = -timeptr->tm_tzadj / 60;
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#else /* !HAVE_TM_NAME */
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#ifdef HAVE_TM_ZONE
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/*
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* Systems with tm_zone probably have tm_gmtoff as
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* secs east of GMT. Convert to mins east of GMT.
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*/
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off = timeptr->tm_gmtoff / 60;
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#else /* !HAVE_TM_ZONE */
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#if HAVE_TZNAME
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/*
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* Systems with tzname[] probably have timezone as
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* secs west of GMT. Convert to mins east of GMT.
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*/
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#ifdef __hpux
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gettimeofday(&tv, &zone);
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off = -zone.tz_minuteswest;
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#else
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off = -(daylight ? timezone : altzone) / 60;
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#endif
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#else /* !HAVE_TZNAME */
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gettimeofday(&tv, &zone);
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off = -zone.tz_minuteswest;
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#endif /* !HAVE_TZNAME */
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#endif /* !HAVE_TM_ZONE */
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#endif /* !HAVE_TM_NAME */
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if (off < 0) {
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tbuf[0] = '-';
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off = -off;
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} else {
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tbuf[0] = '+';
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}
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sprintf(tbuf+1, "%02d%02d", off/60, off%60);
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break;
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#endif /* MAILHEADER_EXT */
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case 'Z': /* time zone name or abbrevation */
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#ifdef HAVE_TZNAME
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i = (daylight && timeptr->tm_isdst > 0); /* 0 or 1 */
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strcpy(tbuf, tzname[i]);
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#else
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#ifdef HAVE_TM_ZONE
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strcpy(tbuf, timeptr->tm_zone);
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#else
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#ifdef HAVE_TM_NAME
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strcpy(tbuf, timeptr->tm_name);
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#else
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gettimeofday(& tv, & zone);
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#ifdef __CYGWIN__
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strcpy(tbuf, timezone());
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#else
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strcpy(tbuf, timezone(zone.tz_minuteswest,
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timeptr->tm_isdst > 0));
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#endif
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#endif /* HAVE_TM_NAME */
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#endif /* HAVE_TM_ZONE */
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#endif /* HAVE_TZNAME */
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break;
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#ifdef SYSV_EXT
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case 'n': /* same as \n */
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tbuf[0] = '\n';
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tbuf[1] = '\0';
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break;
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case 't': /* same as \t */
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tbuf[0] = '\t';
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tbuf[1] = '\0';
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break;
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case 'D': /* date as %m/%d/%y */
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strftime(tbuf, sizeof tbuf, "%m/%d/%y", timeptr);
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break;
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case 'e': /* day of month, blank padded */
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sprintf(tbuf, "%2d", range(1, timeptr->tm_mday, 31));
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break;
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case 'r': /* time as %I:%M:%S %p */
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strftime(tbuf, sizeof tbuf, "%I:%M:%S %p", timeptr);
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break;
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case 'R': /* time as %H:%M */
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strftime(tbuf, sizeof tbuf, "%H:%M", timeptr);
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break;
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case 'T': /* time as %H:%M:%S */
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strftime(tbuf, sizeof tbuf, "%H:%M:%S", timeptr);
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break;
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#endif
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#ifdef SUNOS_EXT
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case 'k': /* hour, 24-hour clock, blank pad */
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sprintf(tbuf, "%2d", range(0, timeptr->tm_hour, 23));
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break;
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case 'l': /* hour, 12-hour clock, 1 - 12, blank pad */
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i = range(0, timeptr->tm_hour, 23);
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if (i == 0)
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i = 12;
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else if (i > 12)
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i -= 12;
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sprintf(tbuf, "%2d", i);
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break;
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#endif
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#ifdef VMS_EXT
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case 'v': /* date as dd-bbb-YYYY */
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sprintf(tbuf, "%2d-%3.3s-%4ld",
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range(1, timeptr->tm_mday, 31),
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months_a[range(0, timeptr->tm_mon, 11)],
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timeptr->tm_year + 1900L);
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for (i = 3; i < 6; i++)
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if (islower(tbuf[i]))
|
|
tbuf[i] = toupper(tbuf[i]);
|
|
break;
|
|
#endif
|
|
|
|
|
|
#ifdef POSIX2_DATE
|
|
case 'C':
|
|
sprintf(tbuf, "%02ld", (timeptr->tm_year + 1900L) / 100);
|
|
break;
|
|
|
|
|
|
case 'E':
|
|
case 'O':
|
|
/* POSIX locale extensions, ignored for now */
|
|
goto again;
|
|
|
|
case 'V': /* week of year according ISO 8601 */
|
|
sprintf(tbuf, "%02d", iso8601wknum(timeptr));
|
|
break;
|
|
|
|
case 'u':
|
|
/* ISO 8601: Weekday as a decimal number [1 (Monday) - 7] */
|
|
sprintf(tbuf, "%d", timeptr->tm_wday == 0 ? 7 :
|
|
timeptr->tm_wday);
|
|
break;
|
|
#endif /* POSIX2_DATE */
|
|
|
|
#ifdef ISO_DATE_EXT
|
|
case 'G':
|
|
case 'g':
|
|
/*
|
|
* Year of ISO week.
|
|
*
|
|
* If it's December but the ISO week number is one,
|
|
* that week is in next year.
|
|
* If it's January but the ISO week number is 52 or
|
|
* 53, that week is in last year.
|
|
* Otherwise, it's this year.
|
|
*/
|
|
w = iso8601wknum(timeptr);
|
|
if (timeptr->tm_mon == 11 && w == 1)
|
|
y = 1900L + timeptr->tm_year + 1;
|
|
else if (timeptr->tm_mon == 0 && w >= 52)
|
|
y = 1900L + timeptr->tm_year - 1;
|
|
else
|
|
y = 1900L + timeptr->tm_year;
|
|
|
|
if (*format == 'G')
|
|
sprintf(tbuf, "%ld", y);
|
|
else
|
|
sprintf(tbuf, "%02ld", y % 100);
|
|
break;
|
|
#endif /* ISO_DATE_EXT */
|
|
default:
|
|
tbuf[0] = '%';
|
|
tbuf[1] = *format;
|
|
tbuf[2] = '\0';
|
|
break;
|
|
}
|
|
i = strlen(tbuf);
|
|
if (i) {
|
|
if (s + i < endp - 1) {
|
|
strcpy(s, tbuf);
|
|
s += i;
|
|
} else
|
|
return 0;
|
|
}
|
|
}
|
|
out:
|
|
if (s < endp && *format == '\0') {
|
|
*s = '\0';
|
|
return (s - start);
|
|
} else
|
|
return 0;
|
|
}
|
|
|
|
/* isleap --- is a year a leap year? */
|
|
|
|
#ifndef __STDC__
|
|
static int
|
|
isleap(year)
|
|
long year;
|
|
#else
|
|
static int
|
|
isleap(long year)
|
|
#endif
|
|
{
|
|
return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
|
|
}
|
|
|
|
|
|
#ifdef POSIX2_DATE
|
|
/* iso8601wknum --- compute week number according to ISO 8601 */
|
|
|
|
#ifndef __STDC__
|
|
static int
|
|
iso8601wknum(timeptr)
|
|
const struct tm *timeptr;
|
|
#else
|
|
static int
|
|
iso8601wknum(const struct tm *timeptr)
|
|
#endif
|
|
{
|
|
/*
|
|
* From 1003.2:
|
|
* If the week (Monday to Sunday) containing January 1
|
|
* has four or more days in the new year, then it is week 1;
|
|
* otherwise it is the highest numbered week of the previous
|
|
* year (52 or 53), and the next week is week 1.
|
|
*
|
|
* ADR: This means if Jan 1 was Monday through Thursday,
|
|
* it was week 1, otherwise week 52 or 53.
|
|
*
|
|
* XPG4 erroneously included POSIX.2 rationale text in the
|
|
* main body of the standard. Thus it requires week 53.
|
|
*/
|
|
|
|
int weeknum, jan1day, diff;
|
|
|
|
/* get week number, Monday as first day of the week */
|
|
weeknum = weeknumber(timeptr, 1);
|
|
|
|
/*
|
|
* With thanks and tip of the hatlo to tml@tik.vtt.fi
|
|
*
|
|
* What day of the week does January 1 fall on?
|
|
* We know that
|
|
* (timeptr->tm_yday - jan1.tm_yday) MOD 7 ==
|
|
* (timeptr->tm_wday - jan1.tm_wday) MOD 7
|
|
* and that
|
|
* jan1.tm_yday == 0
|
|
* and that
|
|
* timeptr->tm_wday MOD 7 == timeptr->tm_wday
|
|
* from which it follows that. . .
|
|
*/
|
|
jan1day = timeptr->tm_wday - (timeptr->tm_yday % 7);
|
|
if (jan1day < 0)
|
|
jan1day += 7;
|
|
|
|
/*
|
|
* If Jan 1 was a Monday through Thursday, it was in
|
|
* week 1. Otherwise it was last year's highest week, which is
|
|
* this year's week 0.
|
|
*
|
|
* What does that mean?
|
|
* If Jan 1 was Monday, the week number is exactly right, it can
|
|
* never be 0.
|
|
* If it was Tuesday through Thursday, the weeknumber is one
|
|
* less than it should be, so we add one.
|
|
* Otherwise, Friday, Saturday or Sunday, the week number is
|
|
* OK, but if it is 0, it needs to be 52 or 53.
|
|
*/
|
|
switch (jan1day) {
|
|
case 1: /* Monday */
|
|
break;
|
|
case 2: /* Tuesday */
|
|
case 3: /* Wednesday */
|
|
case 4: /* Thursday */
|
|
weeknum++;
|
|
break;
|
|
case 5: /* Friday */
|
|
case 6: /* Saturday */
|
|
case 0: /* Sunday */
|
|
if (weeknum == 0) {
|
|
#ifdef USE_BROKEN_XPG4
|
|
/* XPG4 (as of March 1994) says 53 unconditionally */
|
|
weeknum = 53;
|
|
#else
|
|
/* get week number of last week of last year */
|
|
struct tm dec31ly; /* 12/31 last year */
|
|
dec31ly = *timeptr;
|
|
dec31ly.tm_year--;
|
|
dec31ly.tm_mon = 11;
|
|
dec31ly.tm_mday = 31;
|
|
dec31ly.tm_wday = (jan1day == 0) ? 6 : jan1day - 1;
|
|
dec31ly.tm_yday = 364 + isleap(dec31ly.tm_year + 1900L);
|
|
weeknum = iso8601wknum(& dec31ly);
|
|
#endif
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (timeptr->tm_mon == 11) {
|
|
/*
|
|
* The last week of the year
|
|
* can be in week 1 of next year.
|
|
* Sigh.
|
|
*
|
|
* This can only happen if
|
|
* M T W
|
|
* 29 30 31
|
|
* 30 31
|
|
* 31
|
|
*/
|
|
int wday, mday;
|
|
|
|
wday = timeptr->tm_wday;
|
|
mday = timeptr->tm_mday;
|
|
if ( (wday == 1 && (mday >= 29 && mday <= 31))
|
|
|| (wday == 2 && (mday == 30 || mday == 31))
|
|
|| (wday == 3 && mday == 31))
|
|
weeknum = 1;
|
|
}
|
|
|
|
return weeknum;
|
|
}
|
|
#endif
|
|
|
|
/* weeknumber --- figure how many weeks into the year */
|
|
|
|
/* With thanks and tip of the hatlo to ado@elsie.nci.nih.gov */
|
|
|
|
#ifndef __STDC__
|
|
static int
|
|
weeknumber(timeptr, firstweekday)
|
|
const struct tm *timeptr;
|
|
int firstweekday;
|
|
#else
|
|
static int
|
|
weeknumber(const struct tm *timeptr, int firstweekday)
|
|
#endif
|
|
{
|
|
int wday = timeptr->tm_wday;
|
|
int ret;
|
|
|
|
if (firstweekday == 1) {
|
|
if (wday == 0) /* sunday */
|
|
wday = 6;
|
|
else
|
|
wday--;
|
|
}
|
|
ret = ((timeptr->tm_yday + 7 - wday) / 7);
|
|
if (ret < 0)
|
|
ret = 0;
|
|
return ret;
|
|
}
|
|
|
|
#if 0
|
|
/* ADR --- I'm loathe to mess with ado's code ... */
|
|
|
|
Date: Wed, 24 Apr 91 20:54:08 MDT
|
|
From: Michal Jaegermann <audfax!emory!vm.ucs.UAlberta.CA!NTOMCZAK>
|
|
To: arnold@audiofax.com
|
|
|
|
Hi Arnold,
|
|
in a process of fixing of strftime() in libraries on Atari ST I grabbed
|
|
some pieces of code from your own strftime. When doing that it came
|
|
to mind that your weeknumber() function compiles a little bit nicer
|
|
in the following form:
|
|
/*
|
|
* firstweekday is 0 if starting in Sunday, non-zero if in Monday
|
|
*/
|
|
{
|
|
return (timeptr->tm_yday - timeptr->tm_wday +
|
|
(firstweekday ? (timeptr->tm_wday ? 8 : 1) : 7)) / 7;
|
|
}
|
|
How nicer it depends on a compiler, of course, but always a tiny bit.
|
|
|
|
Cheers,
|
|
Michal
|
|
ntomczak@vm.ucs.ualberta.ca
|
|
#endif
|
|
|
|
#ifdef TEST_STRFTIME
|
|
|
|
/*
|
|
* NAME:
|
|
* tst
|
|
*
|
|
* SYNOPSIS:
|
|
* tst
|
|
*
|
|
* DESCRIPTION:
|
|
* "tst" is a test driver for the function "strftime".
|
|
*
|
|
* OPTIONS:
|
|
* None.
|
|
*
|
|
* AUTHOR:
|
|
* Karl Vogel
|
|
* Control Data Systems, Inc.
|
|
* vogelke@c-17igp.wpafb.af.mil
|
|
*
|
|
* BUGS:
|
|
* None noticed yet.
|
|
*
|
|
* COMPILE:
|
|
* cc -o tst -DTEST_STRFTIME strftime.c
|
|
*/
|
|
|
|
/* ADR: I reformatted this to my liking, and deleted some unneeded code. */
|
|
|
|
#ifndef NULL
|
|
#include <stdio.h>
|
|
#endif
|
|
#include <sys/time.h>
|
|
#include <string.h>
|
|
|
|
#define MAXTIME 132
|
|
|
|
/*
|
|
* Array of time formats.
|
|
*/
|
|
|
|
static char *array[] =
|
|
{
|
|
"(%%A) full weekday name, var length (Sunday..Saturday) %A",
|
|
"(%%B) full month name, var length (January..December) %B",
|
|
"(%%C) Century %C",
|
|
"(%%D) date (%%m/%%d/%%y) %D",
|
|
"(%%E) Locale extensions (ignored) %E",
|
|
"(%%H) hour (24-hour clock, 00..23) %H",
|
|
"(%%I) hour (12-hour clock, 01..12) %I",
|
|
"(%%M) minute (00..59) %M",
|
|
"(%%O) Locale extensions (ignored) %O",
|
|
"(%%R) time, 24-hour (%%H:%%M) %R",
|
|
"(%%S) second (00..60) %S",
|
|
"(%%T) time, 24-hour (%%H:%%M:%%S) %T",
|
|
"(%%U) week of year, Sunday as first day of week (00..53) %U",
|
|
"(%%V) week of year according to ISO 8601 %V",
|
|
"(%%W) week of year, Monday as first day of week (00..53) %W",
|
|
"(%%X) appropriate locale time representation (%H:%M:%S) %X",
|
|
"(%%Y) year with century (1970...) %Y",
|
|
"(%%Z) timezone (EDT), or blank if timezone not determinable %Z",
|
|
"(%%a) locale's abbreviated weekday name (Sun..Sat) %a",
|
|
"(%%b) locale's abbreviated month name (Jan..Dec) %b",
|
|
"(%%c) full date (Sat Nov 4 12:02:33 1989)%n%t%t%t %c",
|
|
"(%%d) day of the month (01..31) %d",
|
|
"(%%e) day of the month, blank-padded ( 1..31) %e",
|
|
"(%%h) should be same as (%%b) %h",
|
|
"(%%j) day of the year (001..366) %j",
|
|
"(%%k) hour, 24-hour clock, blank pad ( 0..23) %k",
|
|
"(%%l) hour, 12-hour clock, blank pad ( 0..12) %l",
|
|
"(%%m) month (01..12) %m",
|
|
"(%%p) locale's AM or PM based on 12-hour clock %p",
|
|
"(%%r) time, 12-hour (same as %%I:%%M:%%S %%p) %r",
|
|
"(%%u) ISO 8601: Weekday as decimal number [1 (Monday) - 7] %u",
|
|
"(%%v) VMS date (dd-bbb-YYYY) %v",
|
|
"(%%w) day of week (0..6, Sunday == 0) %w",
|
|
"(%%x) appropriate locale date representation %x",
|
|
"(%%y) last two digits of year (00..99) %y",
|
|
"(%%z) timezone offset east of GMT as HHMM (e.g. -0500) %z",
|
|
(char *) NULL
|
|
};
|
|
|
|
/* main routine. */
|
|
|
|
int
|
|
main(argc, argv)
|
|
int argc;
|
|
char **argv;
|
|
{
|
|
long time();
|
|
|
|
char *next;
|
|
char string[MAXTIME];
|
|
|
|
int k;
|
|
int length;
|
|
|
|
struct tm *tm;
|
|
|
|
long clock;
|
|
|
|
/* Call the function. */
|
|
|
|
clock = time((long *) 0);
|
|
tm = localtime(&clock);
|
|
|
|
for (k = 0; next = array[k]; k++) {
|
|
length = strftime(string, MAXTIME, next, tm);
|
|
printf("%s\n", string);
|
|
}
|
|
|
|
exit(0);
|
|
}
|
|
#endif /* TEST_STRFTIME */
|