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DateFormat(3)	      User Contributed Perl Documentation	 DateFormat(3)

       Log::Log4perl::DateFormat - Log4perl advanced date formatter helper

	     # Either in a log4j.conf file ...
	   log4perl.appender.Logfile.layout = \
	   log4perl.appender.Logfile.layout.ConversionPattern =	%d{MM/dd HH:mm}	%m

	     # ... or via the PatternLayout class ...
	   use Log::Log4perl::Layout::PatternLayout;
	   my $layout =	Log::Log4perl::Layout::PatternLayout->new(
	       "%d{HH:mm:ss,SSS} %m");

	     # ... or even directly with this helper class:
	   use Log::Log4perl::DateFormat;
	   my $format =	Log::Log4perl::DateFormat->new("HH:mm:ss,SSS");
	   my $time = time();
	   print $format->format($time), "\n";
	       # => "17:02:39,000"

       "Log::Log4perl::DateFormat" is a	helper class for the advanced date
       formatting functions in "Log::Log4perl::Layout::PatternLayout", and
       adheres (mostly)	to the log4j SimpleDateFormat spec available on

       It supports the following placeholders:

	   Symbol Meaning	       Presentation    Example
	   ------ -------	       ------------    -------
	   G	  era designator       (Text)	       AD
	   e	  epoch	seconds	       (Number)	       1315011604
	   y	  year		       (Number)	       1996
	   M	  month	in year	       (Text & Number) July & 07
	   d	  day in month	       (Number)	       10
	   h	  hour in am/pm	(1~12) (Number)	       12
	   H	  hour in day (0~23)   (Number)	       0
	   m	  minute in hour       (Number)	       30
	   s	  second in minute     (Number)	       55
	   S	  millisecond	       (Number)	       978
	   E	  day in week	       (Text)	       Tuesday
	   D	  day in year	       (Number)	       189
	   F	  day of week in month (Number)	       2 (2nd Wed in July)
	   w	  week in year	       (Number)	       27
	   W	  week in month	       (Number)	       2
	   a	  am/pm	marker	       (Text)	       PM
	   k	  hour in day (1~24)   (Number)	       24
	   K	  hour in am/pm	(0~11) (Number)	       0
	   z	  time zone	       (Text)	       Pacific Standard	Time
	   Z	  RFC 822 time zone    (Text)	       -0800
	   '	  escape for text      (Delimiter)
	   ''	  single quote	       (Literal)       '

	   Presentation	explanation:

	   (Text): 4 or	more pattern letters--use full form, < 4--use short or
		   abbreviated form if one exists.

	   (Number): the minimum number	of digits. Shorter numbers are
		     zero-padded to this amount. Year is handled
		     specially;	that is, if the	count of 'y' is	2, the
		     Year will be truncated to 2 digits.

	   (Text & Number): 3 or over, use text, otherwise use number.

       For example, if you want	to format the current Unix time	in "MM/dd
       HH:mm" format, all you have to do is specify it in the %d{...} section
       of the PatternLayout in a Log4perl configuration	file:

	   # log4j.conf
	   # ...
	   log4perl.appender.Logfile.layout = \
	   log4perl.appender.Logfile.layout.ConversionPattern =	%d{MM/dd HH:mm}	%m

       Same goes for Perl code defining	a PatternLayout	for Log4perl:

	   use Log::Log4perl::Layout::PatternLayout;
	   my $layout =	Log::Log4perl::Layout::PatternLayout->new(
	       "%d{MM/dd HH:mm}	%m");

       Or, on a	lower level, you can use the class directly:

	   use Log::Log4perl::DateFormat;
	   my $format =	Log::Log4perl::DateFormat->new("MM/dd HH:mm");
	   my $time = time();
	   print $format->format($time), "\n";

       While the "new()" method	is expensive, because it parses	the format
       strings and sets	up all kinds of	structures behind the scenes, followup
       calls to	"format()" are fast, because "DateFormat" will just call
       "localtime()" and "sprintf()" once to return the	formatted date/time

       So, typically, you would	initialize the formatter once and then reuse
       it over and over	again to display all kinds of time values.

       Also, for your convenience, the following predefined formats are
       available, just as outlined in the log4j	spec:

	   Format   Equivalent			   Example
	   ABSOLUTE "HH:mm:ss,SSS"		   "15:49:37,459"
	   DATE	    "dd	MMM yyyy HH:mm:ss,SSS"	   "06 Nov 1994	15:49:37,459"
	   ISO8601  "yyyy-MM-dd	HH:mm:ss,SSS"	   "1999-11-27 15:49:37,459"
	   APACHE   "[EEE MMM dd HH:mm:ss yyyy]"   "[Wed Mar 16	15:49:37 2005]"

       So, instead of passing


       you could just as well say


       and get the same	result later on.

   Known Shortcomings
       The following placeholders are currently	not recognized,	unless someone
       (and that could be you :) implements them:

	   F day of week in month
	   w week in year
	   W week in month
	   k hour in day
	   K hour in am/pm
	   z timezone (but we got 'Z' for the numeric time zone	value)

       Also, "Log::Log4perl::DateFormat" just knows about English week and
       month names, internationalization support has to	be added.

Millisecond Times
       More granular timestamps	down to	the millisecond	are also supported,
       just provide the	millsecond count as a second argument:

	   # Advanced time, resultion in milliseconds
	   use Time::HiRes;
	   my ($secs, $msecs) =	Time::HiRes::gettimeofday();
	   print $format->format($secs,	$msecs), "\n";
	       # => "17:02:39,959"

       Copyright 2002-2016 by Mike Schilli <> and Kevin Goess

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       Please contribute patches to the	project	on Github:

       Send bug	reports	or requests for	enhancements to	the authors via	our

       MAILING LIST (questions,	bug reports, suggestions/patches):

       Authors (please contact them via	the list above,	not directly): Mike
       Schilli <>, Kevin Goess	<>

       Contributors (in	alphabetical order): Ateeq Altaf, Cory Bennett,	Jens
       Berthold, Jeremy	Bopp, Hutton Davidson, Chris R.	Donnelly, Matisse
       Enzer, Hugh Esco, Anthony Foiani, James FitzGibbon, Carl	Franks,	Dennis
       Gregorovic, Andy	Grundman, Paul Harrington, Alexander Hartmaier	David
       Hull, Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter,
       Brett Rann, Peter Rabbitson, Erik Selberg, Aaron	Straup Cope, Lars
       Thegler,	David Viner, Mac Yang.

perl v5.32.1			  2020-07-22			 DateFormat(3)


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