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<HTML><HEAD><TITLE>Recipe 3.1. Finding Today's Date (Perl Cookbook)</TITLE><METANAME="DC.title"CONTENT="Perl Cookbook"><METANAME="DC.creator"CONTENT="Tom Christiansen & Nathan Torkington"><METANAME="DC.publisher"CONTENT="O'Reilly & Associates, Inc."><METANAME="DC.date"CONTENT="1999-07-02T01:30:33Z"><METANAME="DC.type"CONTENT="Text.Monograph"><METANAME="DC.format"CONTENT="text/html"SCHEME="MIME"><METANAME="DC.source"CONTENT="1-56592-243-3"SCHEME="ISBN"><METANAME="DC.language"CONTENT="en-US"><METANAME="generator"CONTENT="Jade 1.1/O'Reilly DocBook 3.0 to HTML 4.0"><LINKREV="made"HREF="mailto:online-books@oreilly.com"TITLE="Online Books Comments"><LINKREL="up"HREF="ch03_01.htm"TITLE="3. Dates and Times"><LINKREL="prev"HREF="ch03_01.htm"TITLE="3.0. Introduction"><LINKREL="next"HREF="ch03_03.htm"TITLE="3.2. Converting DMYHMS to Epoch Seconds"></HEAD><BODYBGCOLOR="#FFFFFF"><img alt="Book Home" border="0" src="gifs/smbanner.gif" usemap="#banner-map" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Perl Cookbook"><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><p><TABLEWIDTH="684"BORDER="0"CELLSPACING="0"CELLPADDING="0"><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="228"><ACLASS="sect1"HREF="ch03_01.htm"TITLE="3.0. Introduction"><IMGSRC="../gifs/txtpreva.gif"ALT="Previous: 3.0. Introduction"BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="228"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1"><ACLASS="chapter"REL="up"HREF="ch03_01.htm"TITLE="3. Dates and Times"></A></FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="228"><ACLASS="sect1"HREF="ch03_03.htm"TITLE="3.2. Converting DMYHMS to Epoch Seconds"><IMGSRC="../gifs/txtnexta.gif"ALT="Next: 3.2. Converting DMYHMS to Epoch Seconds"BORDER="0"></A></TD></TR></TABLE></DIV><DIVCLASS="sect1"><H2CLASS="sect1"><ACLASS="title"NAME="ch03-15819">3.1. Finding Today's Date</A></H2><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-92">Problem <ACLASS="indexterm"NAME="ch03-idx-1000006236-0"></A><ACLASS="indexterm"NAME="ch03-idx-1000006236-1"></A></A></H3><PCLASS="para">You need to find the year, month, and day values for today's date.</P></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-98">Solution</A></H3><PCLASS="para">Use <CODECLASS="literal">localtime</CODE>, which returns values for the current date and time if given no arguments. You can either use <CODECLASS="literal">localtime</CODE> and extract the information you want from the list it returns:</P><PRECLASS="programlisting">($DAY, $MONTH, $YEAR) = (localtime)[3,4,5];</PRE><PCLASS="para">Or, use Time::localtime, which overrides <CODECLASS="literal">localtime</CODE> to return a Time::tm object:</P><PRECLASS="programlisting">use Time::localtime;$tm = localtime;($DAY, $MONTH, $YEAR) = ($tm->mday, $tm->mon, $tm->year);</PRE></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-114">Discussion</A></H3><PCLASS="para">Here's how you'd print the current date as "YYYY-MM-DD," using the non-overridden <CODECLASS="literal">localtime</CODE>:</P><PRECLASS="programlisting">($day, $month, $year) = (localtime)[3,4,5];printf("The current date is %04d %02d %02d\n", $year+1900, $month+1, $day);<CODECLASS="userinput"><B><CODECLASS="replaceable"><I>The current date is 1998 04 28</I></CODE></B></CODE></PRE><PCLASS="para">To extract the fields we want from the list returned by <CODECLASS="literal">localtime</CODE>, we take a list slice. We could also have written it as:</P><PRECLASS="programlisting">($day, $month, $year) = (localtime)[3..5];</PRE><PCLASS="para">This is how we'd print the current date as "YYYY-MM-DD" (in approved ISO 8601 fashion), using Time::localtime:</P><PRECLASS="programlisting">use Time::localtime;$tm = localtime;printf("The current date is %04d-%02d-%02d\n", $tm->year+1900, ($tm->mon)+1, $tm->mday);<CODECLASS="userinput"><B><CODECLASS="replaceable"><I>The current date is 1998-04-28</I></CODE></B></CODE></PRE><PCLASS="para">The object interface might look out of place in a short program. However, when you do a lot of work with the distinct values, accessing them by name makes code much easier to understand.</P><PCLASS="para">A more obfuscated way that does not involve introducing temporary variables is:</P><PRECLASS="programlisting">printf("The current date is %04d-%02d-%02d\n", sub {($_[5]+1900, $_[4]+1, $_[3])}->(localtime));</PRE><PCLASS="para">There is also <CODECLASS="literal">strftime</CODE> from the POSIX module discussed in <ACLASS="xref"HREF="ch03_09.htm"TITLE="Printing a Date">Recipe 3.8</A>:</P><PRECLASS="programlisting">use POSIX qw(strftime);print strftime "%Y-%m-%d\n", localtime;<ACLASS="indexterm"NAME="ch03-idx-1000006239-0"></A><ACLASS="indexterm"NAME="ch03-idx-1000006239-1"></A></PRE><PCLASS="para">The <CODECLASS="literal">gmtime</CODE> function works just as <CODECLASS="literal">localtime</CODE> does, but gives the answer in GMT instead of your local time zone.</P></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-1000006630">See Also</A></H3><PCLASS="para">The <CODECLASS="literal">localtime</CODE> and <CODECLASS="literal">gmtime</CODE> functions in <EMCLASS="emphasis">perlfunc </EM>(1) and <ACLASS="olink"HREF="../prog/ch03_01.htm">Chapter 3</A> of <ACLASS="citetitle"HREF="../prog/index.htm"TITLE="Programming Perl"><CITECLASS="citetitle">Programming Perl</CITE></A>; the documentation for the standard Time::localtime module</P></DIV></DIV><DIVCLASS="htmlnav"><P></P><HRALIGN="LEFT"WIDTH="684"TITLE="footer"><TABLEWIDTH="684"BORDER="0"CELLSPACING="0"CELLPADDING="0"><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="228"><ACLASS="sect1"HREF="ch03_01.htm"TITLE="3.0. 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