Blame exp_strf.c

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/* exp_strp.c - functions for exp_timestamp */
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/*
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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 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 <arnold@skeeve.atl.ga.us>
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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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 *
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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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 *
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 *
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 * Modified by Don Libes for Expect, 10/93 and 12/95.
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 * Forced POSIX semantics.
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 * Replaced inline/min/max stuff with a single range function.
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 * Removed tzset stuff.
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 * Commented out tzname stuff.
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 *
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 * According to Arnold, the current version of this code can ftp'd from
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 * ftp.mathcs.emory.edu:/pub/arnold/strftime.shar.gz
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 *
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 */
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#include "expect_cf.h"
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#include "tcl.h"
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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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/* according to Karl Vogel, time.h is insufficient on Pyramid */
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/* following is recommended by autoconf */
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#ifdef TIME_WITH_SYS_TIME
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# include <sys/time.h>
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# include <time.h>
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#else
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# ifdef HAVE_SYS_TIME_H
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#  include <sys/time.h>
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# else
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#  include <time.h>
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# endif
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#endif
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#include <sys/types.h>
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#define SYSV_EXT	1	/* stuff in System V ascftime routine */
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#define POSIX2_DATE	1	/* stuff in Posix 1003.2 date command */
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#if defined(POSIX2_DATE) && ! defined(SYSV_EXT)
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#define SYSV_EXT	1
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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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#ifndef __STDC__
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#define const
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extern char *getenv();
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static int weeknumber();
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adddecl(static int iso8601wknum();)
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#else
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#ifndef strchr
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extern char *strchr(const char *str, int ch);
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#endif
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extern char *getenv(const char *v);
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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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/* attempt to use strftime to compute timezone, else fallback to */
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/* less portable ways */
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#if !defined(HAVE_STRFTIME)
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# if defined(HAVE_SV_TIMEZONE)
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extern char *tzname[2];
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extern int daylight;
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# else
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#  if defined(HAVE_TIMEZONE)
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char           *
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zone_name (tp)
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struct tm      *tp;
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{
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	char           *timezone ();
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	struct timeval  tv;
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	struct timezone tz;
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	gettimeofday (&tv, &tz;;
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	return timezone (tz.tz_minuteswest, tp->tm_isdst);
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}
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#  endif /* HAVE_TIMEZONE */
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# endif /* HAVE_SV_TIMEZONE */
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#endif /* HAVE_STRFTIME */
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static int
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range(low,item,hi)
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int low, item, hi;
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{
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	if (item < low) return low;
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	if (item > hi) return hi;
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	return item;
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}
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/* strftime --- produce formatted time */
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void
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/*size_t*/
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#ifndef __STDC__
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exp_strftime(/*s,*/ format, timeptr, dstring)
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/*char *s;*/
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char *format;
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const struct tm *timeptr;
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Tcl_DString *dstring;
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#else
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/*exp_strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)*/
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exp_strftime(char *format, const struct tm *timeptr,Tcl_DString *dstring)
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#endif
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{
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	int copied;	/* used to suppress copying when called recursively */
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#if 0
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	char *endp = s + maxsize;
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	char *start = s;
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#endif
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	char *percentptr;
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	char tbuf[100];
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	int i;
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	/* various tables, useful in North America */
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	static 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 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 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 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 char *ampm[] = { "AM", "PM", };
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/*	for (; *format && s < endp - 1; format++) {*/
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	for (; *format ; format++) {
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		tbuf[0] = '\0';
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		copied = 0;		/* has not been copied yet */
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		percentptr = strchr(format,'%');
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		if (percentptr == 0) {
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			Tcl_DStringAppend(dstring,format,-1);
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			goto out;
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		} else if (percentptr != format) {
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			Tcl_DStringAppend(dstring,format,percentptr - format);
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			format = percentptr;
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	        }
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#if 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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#endif
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	again:
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		switch (*++format) {
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		case '\0':
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			Tcl_DStringAppend(dstring,"%",1);
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#if 0
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			*s++ = '%';
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#endif
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			goto out;
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		case '%':
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			Tcl_DStringAppend(dstring,"%",1);
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			copied = 1;
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			break;
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#if 0
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			*s++ = '%';
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			continue;
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#endif
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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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			sprintf(tbuf, "%s %s %2d %02d:%02d:%02d %d",
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				days_a[range(0, timeptr->tm_wday, 6)],
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				months_a[range(0, timeptr->tm_mon, 11)],
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				range(1, timeptr->tm_mday, 31),
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				range(0, timeptr->tm_hour, 23),
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				range(0, timeptr->tm_min, 59),
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				range(0, timeptr->tm_sec, 61),
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				timeptr->tm_year + 1900);
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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 - 61 */
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			i = range(0, timeptr->tm_sec, 61);
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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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			sprintf(tbuf, "%s %s %2d %d",
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				days_a[range(0, timeptr->tm_wday, 6)],
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				months_a[range(0, timeptr->tm_mon, 11)],
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				range(1, timeptr->tm_mday, 31),
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				timeptr->tm_year + 1900);
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			break;
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		case 'X':	/* appropriate time representation */
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			sprintf(tbuf, "%02d:%02d:%02d",
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				range(0, timeptr->tm_hour, 23),
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				range(0, timeptr->tm_min, 59),
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				range(0, timeptr->tm_sec, 61));
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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, "%d", 1900 + timeptr->tm_year);
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			break;
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		case 'Z':	/* time zone name or abbrevation */
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#if defined(HAVE_STRFTIME)
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			strftime(tbuf,sizeof tbuf,"%Z",timeptr);
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#else
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# if defined(HAVE_SV_TIMEZONE)
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			i = 0;
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			if (daylight && timeptr->tm_isdst)
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				i = 1;
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			strcpy(tbuf, tzname[i]);
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# else
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			strcpy(tbuf, zone_name (timeptr));
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#  if defined(HAVE_TIMEZONE)
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#  endif /* HAVE_TIMEZONE */
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			/* no timezone available */
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			/* feel free to add others here */
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# endif /* HAVE_SV_TIMEZONE */
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#endif /* HAVE STRFTIME */
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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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			exp_strftime("%m/%d/%y", timeptr, dstring);
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			copied = 1;
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/*			exp_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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			exp_strftime("%I:%M:%S %p", timeptr, dstring);
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			copied = 1;
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/*			exp_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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			exp_strftime("%H:%M", timeptr, dstring);
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			copied = 1;
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/*			exp_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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			exp_strftime("%H:%M:%S", timeptr, dstring);
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			copied = 1;
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/*			exp_strftime(tbuf, sizeof tbuf, "%H:%M:%S", timeptr);*/
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			break;
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#endif
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#ifdef POSIX2_DATE
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		case 'C':
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			sprintf(tbuf, "%02d", (timeptr->tm_year + 1900) / 100);
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			break;
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		case 'E':
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		case 'O':
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			/* POSIX locale extensions, ignored for now */
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			goto again;
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		case 'V':	/* week of year according ISO 8601 */
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			sprintf(tbuf, "%02d", iso8601wknum(timeptr));
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			break;
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		case 'u':
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		/* ISO 8601: Weekday as a decimal number [1 (Monday) - 7] */
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			sprintf(tbuf, "%d", timeptr->tm_wday == 0 ? 7 :
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					timeptr->tm_wday);
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			break;
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#endif	/* POSIX2_DATE */
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		default:
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			tbuf[0] = '%';
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			tbuf[1] = *format;
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			tbuf[2] = '\0';
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			break;
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		}
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		if (!copied)
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			Tcl_DStringAppend(dstring,tbuf,-1);
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#if 0
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		i = strlen(tbuf);
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		if (i) {
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			if (s + i < endp - 1) {
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				strcpy(s, tbuf);
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				s += i;
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			} else
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				return 0;
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#endif
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	}
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out:;
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#if 0
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	if (s < endp && *format == '\0') {
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		*s = '\0';
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		return (s - start);
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	} else
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		return 0;
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#endif
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}
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/* isleap --- is a year a leap year? */
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#ifndef __STDC__
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static int
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isleap(year)
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int year;
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#else
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static int
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isleap(int year)
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#endif
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{
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	return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
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}
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#ifdef POSIX2_DATE
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/* iso8601wknum --- compute week number according to ISO 8601 */
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#ifndef __STDC__
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static int
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iso8601wknum(timeptr)
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const struct tm *timeptr;
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#else
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static int
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iso8601wknum(const struct tm *timeptr)
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#endif
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{
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	/*
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	 * From 1003.2:
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	 *	If the week (Monday to Sunday) containing January 1
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	 *	has four or more days in the new year, then it is week 1;
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	 *	otherwise it is the highest numbered week of the previous
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	 *	(52 or 53) year, and the next week is week 1.
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	 *
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	 * ADR: This means if Jan 1 was Monday through Thursday,
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	 *	it was week 1, otherwise week 53.
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	 * 
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	 * XPG4 erroneously included POSIX.2 rationale text in the
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	 * main body of the standard. Thus it requires week 53.
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	 */
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	int weeknum, jan1day;
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	/* get week number, Monday as first day of the week */
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	weeknum = weeknumber(timeptr, 1);
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	/*
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	 * With thanks and tip of the hatlo to tml@tik.vtt.fi
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	 *
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	 * What day of the week does January 1 fall on?
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	 * We know that
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	 *	(timeptr->tm_yday - jan1.tm_yday) MOD 7 ==
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	 *		(timeptr->tm_wday - jan1.tm_wday) MOD 7
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	 * and that
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	 * 	jan1.tm_yday == 0
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	 * and that
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	 * 	timeptr->tm_wday MOD 7 == timeptr->tm_wday
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	 * from which it follows that. . .
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 	 */
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	jan1day = timeptr->tm_wday - (timeptr->tm_yday % 7);
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	if (jan1day < 0)
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		jan1day += 7;
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	/*
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	 * If Jan 1 was a Monday through Thursday, it was in
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	 * week 1.  Otherwise it was last year's highest week, which is
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	 * this year's week 0.
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	 *
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	 * What does that mean?
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	 * If Jan 1 was Monday, the week number is exactly right, it can
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	 *	never be 0.
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	 * If it was Tuesday through Thursday, the weeknumber is one
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	 *	less than it should be, so we add one.
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	 * Otherwise, Friday, Saturday or Sunday, the week number is
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	 * OK, but if it is 0, it needs to be 52 or 53.
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	 */
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	switch (jan1day) {
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	case 1:		/* Monday */
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		break;
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	case 2:		/* Tuesday */
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	case 3:		/* Wednesday */
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	case 4:		/* Thursday */
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		weeknum++;
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		break;
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	case 5:		/* Friday */
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	case 6:		/* Saturday */
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	case 0:		/* Sunday */
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		if (weeknum == 0) {
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#ifdef USE_BROKEN_XPG4
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			/* XPG4 (as of March 1994) says 53 unconditionally */
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			weeknum = 53;
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#else
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			/* get week number of last week of last year */
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			struct tm dec31ly;	/* 12/31 last year */
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			dec31ly = *timeptr;
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			dec31ly.tm_year--;
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			dec31ly.tm_mon = 11;
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			dec31ly.tm_mday = 31;
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			dec31ly.tm_wday = (jan1day == 0) ? 6 : jan1day - 1;
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			dec31ly.tm_yday = 364 + isleap(dec31ly.tm_year + 1900);
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			weeknum = iso8601wknum(& dec31ly);
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#endif
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		}
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		break;
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	}
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	if (timeptr->tm_mon == 11) {
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		/*
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		 * The last week of the year
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		 * can be in week 1 of next year.
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		 * Sigh.
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		 *
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		 * This can only happen if
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		 *	M   T  W
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		 *	29  30 31
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		 *	30  31
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		 *	31
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		 */
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		int wday, mday;
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		wday = timeptr->tm_wday;
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		mday = timeptr->tm_mday;
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		if (   (wday == 1 && (mday >= 29 && mday <= 31))
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		    || (wday == 2 && (mday == 30 || mday == 31))
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		    || (wday == 3 &&  mday == 31))
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			weeknum = 1;
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	}
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	return weeknum;
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}
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#endif
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/* weeknumber --- figure how many weeks into the year */
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/* With thanks and tip of the hatlo to ado@elsie.nci.nih.gov */
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#ifndef __STDC__
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static int
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weeknumber(timeptr, firstweekday)
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const struct tm *timeptr;
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int firstweekday;
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#else
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static int
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weeknumber(const struct tm *timeptr, int firstweekday)
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#endif
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{
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	int wday = timeptr->tm_wday;
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	int ret;
Packit a69f91
Packit a69f91
	if (firstweekday == 1) {
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		if (wday == 0)	/* sunday */
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			wday = 6;
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		else
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			wday--;
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	}
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	ret = ((timeptr->tm_yday + 7 - wday) / 7);
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	if (ret < 0)
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		ret = 0;
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	return ret;
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}