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STRPTIME(3)		   Linux Programmer's Manual		   STRPTIME(3)

NAME
       strptime	 - convert a string representation of time to a	time tm	struc-
       ture

SYNOPSIS
       #define _XOPEN_SOURCE /*	glibc2 needs this */
       #include	<time.h>

       char *strptime(const char *s, const char	*format, struct	tm *tm);

DESCRIPTION
       The strptime() function is the converse function	to strftime() and con-
       verts  the  character string pointed to by s to values which are	stored
       in the tm structure pointed to by tm, using  the	 format	 specified  by
       format.	 Here  format  is  a  character	 string	that consists of field
       descriptors and text characters,	reminiscent of scanf(3).   Each	 field
       descriptor consists of a	% character followed by	another	character that
       specifies the replacement for the field descriptor.  All	other  charac-
       ters  in	 the format string must	have a matching	character in the input
       string, except for whitespace, which matches zero  or  more  whitespace
       characters  in  the  input string.  There should	be whitespace or other
       alphanumeric characters between any two field descriptors.

       The strptime() function processes the input string from left to	right.
       Each of the three possible input	elements (whitespace, literal, or for-
       mat) are	handled	one after the other.  If the input cannot  be  matched
       to  the	format string the function stops.  The remainder of the	format
       and input strings are not processed.

       The supported input field descriptors are listed	below.	In case	a text
       string (such as a weekday or month name)	is to be matched, the compari-
       son is case insensitive.	 In case a number is to	 be  matched,  leading
       zeros are permitted but not required.

       %%     The % character.

       %a or %A
	      The weekday name according to the	current	locale,	in abbreviated
	      form or the full name.

       %b or %B	or %h
	      The month	name according to the current locale,  in  abbreviated
	      form or the full name.

       %c     The date and time	representation for the current locale.

       %C     The century number (0-99).

       %d or %e
	      The day of month (1-31).

       %D     Equivalent  to  %m/%d/%y.	(This is the American style date, very
	      confusing	to non-Americans, especially since %d/%m/%y is	widely
	      used in Europe.  The ISO 8601 standard format is %Y-%m-%d.)

       %H     The hour (0-23).

       %I     The hour on a 12-hour clock (1-12).

       %j     The day number in	the year (1-366).

       %m     The month	number (1-12).

       %M     The minute (0-59).

       %n     Arbitrary	whitespace.

       %p     The  locale's equivalent of AM or	PM. (Note: there may be	none.)

       %r     The 12-hour clock	time (using the	locale's AM or	PM).   In  the
	      POSIX  locale equivalent to %I:%M:%S %p.	If t_fmt_ampm is empty
	      in the LC_TIME part of the current locale	then the behaviour  is
	      undefined.

       %R     Equivalent to %H:%M.

       %S     The second (0-60;	60 may occur for leap seconds; earlier also 61
	      was allowed).

       %t     Arbitrary	whitespace.

       %T     Equivalent to %H:%M:%S.

       %U     The week number with Sunday the first day	of  the	 week  (0-53).
	      The first	Sunday of January is the first day of week 1.

       %w     The weekday number (0-6) with Sunday = 0.

       %W     The  week	 number	 with Monday the first day of the week (0-53).
	      The first	Monday of January is the first day of week 1.

       %x     The date,	using the locale's date	format.

       %X     The time,	using the locale's time	format.

       %y     The year within century (0-99).  When a century is not otherwise
	      specified, values	in the range 69-99 refer to years in the twen-
	      tieth century (1969-1999); values	in the range  00-68  refer  to
	      years in the twenty-first	century	(2000-2068).

       %Y     The year,	including century (for example,	1991).

       Some  field  descriptors	can be modified	by the E or O modifier charac-
       ters to indicate	that an	alternative format or specification should  be
       used.  If the alternative format	or specification does not exist	in the
       current locale, the unmodified field descriptor is used.

       The E modifier specifies	that the input string may contain  alternative
       locale-dependent	versions of the	date and time representation:

       %Ec    The locale's alternative date and	time representation.

       %EC    The  name	 of the	base year (period) in the locale's alternative
	      representation.

       %Ex    The locale's alternative date representation.

       %EX    The locale's alternative time representation.

       %Ey    The offset from %EC (year	only) in the locale's alternative rep-
	      resentation.

       %EY    The full alternative year	representation.

       The O modifier specifies	that the numerical input may be	in an alterna-
       tive locale-dependent format:

       %Od or %Oe
	      The day of the month using the locale's alternative numeric sym-
	      bols; leading zeros are permitted	but not	required.

       %OH    The  hour	(24-hour clock)	using the locale's alternative numeric
	      symbols.

       %OI    The hour (12-hour	clock) using the locale's alternative  numeric
	      symbols.

       %Om    The month	using the locale's alternative numeric symbols.

       %OM    The minutes using	the locale's alternative numeric symbols.

       %OS    The seconds using	the locale's alternative numeric symbols.

       %OU    The  week	 number	 of  the  year (Sunday as the first day	of the
	      week) using the locale's alternative numeric symbols.

       %Ow    The number of the	weekday	(Sunday=0) using the locale's alterna-
	      tive numeric symbols.

       %OW    The  week	 number	 of  the  year (Monday as the first day	of the
	      week) using the locale's alternative numeric symbols.

       %Oy    The year (offset from %C)	using the locale's alternative numeric
	      symbols.

       The broken-down time structure tm is defined in _time.h_	as follows:

	      struct tm	{
		      int     tm_sec;	      /* seconds */
		      int     tm_min;	      /* minutes */
		      int     tm_hour;	      /* hours */
		      int     tm_mday;	      /* day of	the month */
		      int     tm_mon;	      /* month */
		      int     tm_year;	      /* year */
		      int     tm_wday;	      /* day of	the week */
		      int     tm_yday;	      /* day in	the year */
		      int     tm_isdst;	      /* daylight saving time */
	      };

RETURN VALUE
       The  return  value  of the function is a	pointer	to the first character
       not processed in	this function call.  In	case the input string contains
       more  characters	 than  required	 by the	format string the return value
       points right after the last consumed  input  character.	 In  case  the
       whole  input string is consumed the return value	points to the NUL byte
       at the end of the string.  If strptime()	fails to match all of the for-
       mat string and therefore	an error occurred the function returns NULL.

CONFORMING TO
       XPG4, SUSv2, POSIX 1003.1-2001.

EXAMPLE
       The  following  example	demonstrates  the  use of strptime() and strf-
       time().

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

       int main() {
	       struct tm tm;
	       char buf[255];

	       strptime("2001-11-12 18:31:01", "%Y-%m-%d %H:%M:%S", &tm);
	       strftime(buf, sizeof(buf), "%d %b %Y %H:%M", &tm);
	       puts(buf);
	       return 0;
       }

GNU EXTENSIONS
       For reasons of symmetry,	glibc tries to support for strptime  the  same
       format  characters  as  for strftime.  (In most cases the corresponding
       fields are parsed, but no field in tm is	changed.)  This	leads to

       %F     Equivalent to %Y-%m-%d, the ISO 8601 date	format.

       %g     The year corresponding to	the ISO	week number, but  without  the
	      century (0-99).

       %G     The  year	 corresponding	to  the	ISO week number. (For example,
	      1991.)

       %u     The day of the week as a decimal number (1-7, where Monday = 1).

       %V     The  ISO	8601:1988  week	number as a decimal number (1-53).  If
	      the week (starting on Monday) containing 1 January has  four  or
	      more  days in the	new year, then it is considered	week 1.	Other-
	      wise, it is the last week	of the previous	 year,	and  the  next
	      week is week 1.

       %z     An RFC-822/ISO 8601 standard time	zone specification.

       %Z     The timezone name.

       Similarly,  because  of GNU extensions to strftime, %k is accepted as a
       synonym for %H, and %l should be	accepted as a synonym for %I,  and  %P
       is accepted as a	synonym	for %p.	 Finally

       %s     The  number  of  seconds since the epoch,	i.e., since 1970-01-01
	      00:00:00 UTC.  Leap seconds are not counted unless  leap	second
	      support is available.

       The  GNU	 libc  implementation  does not	require	whitespace between two
       field descriptors.

NOTES
       In principle, this function does	not initialize tm but only stores  the
       values  specified.  This	means that tm should be	initialized before the
       call.  Details differ a bit between different Unix  systems.   The  GNU
       libc  implementation  does not touch those fields which are not explic-
       itly specified, except that it recomputes the tm_wday and tm_yday field
       if any of the year, month, or day elements changed.

       This  function  is  available  since libc 4.6.8.	 Linux libc4 and libc5
       includes	define the prototype unconditionally; glibc2 includes  provide
       a prototype only	when _XOPEN_SOURCE or _GNU_SOURCE are defined.

       Before  libc 5.4.13 whitespace (and the 'n' and 't' specifications) was
       not handled, no 'E' and 'O' locale modifier characters  were  accepted,
       and the 'C' specification was a synonym for the 'c' specification.

       The  'y'	 (year in century) specification is taken to specify a year in
       the 20th	century	by libc4 and libc5. It is taken	to be a	 year  in  the
       range  1950-2049	 by  glibc  2.0. It is taken to	be a year in 1969-2068
       since glibc 2.1.

SEE ALSO
       time(2),	getdate(3), scanf(3), setlocale(3), strftime(3)

GNU				  2001-11-12			   STRPTIME(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | EXAMPLE | GNU EXTENSIONS | NOTES | SEE ALSO

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