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<HTML><HEAD><TITLE>Recipe 3.3. Converting Epoch Seconds to DMYHMS (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="1999-07-02T01:30:36Z"><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_03.htm"TITLE="3.2. Converting DMYHMS to Epoch Seconds"><LINKREL="next"HREF="ch03_05.htm"TITLE="3.4. 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Adding to or Subtracting from a Date"><IMGSRC="../gifs/txtnexta.gif"ALT="Next: 3.4. Adding to or Subtracting from a Date"BORDER="0"></A></TD></TR></TABLE></DIV><DIVCLASS="sect1"><H2CLASS="sect1"><ACLASS="title"NAME="ch03-41138">3.3. Converting Epoch Seconds to DMYHMS</A></H2><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-228">Problem</A></H3><PCLASS="para">You have a date and time in Epoch seconds, and you want to calculate individual DMYHMS values from it.</P></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-234">Solution</A></H3><PCLASS="para">Use the <CODECLASS="literal">localtime</CODE><ACLASS="indexterm"NAME="ch03-idx-1000006268-0"></A> or <CODECLASS="literal">gmtime</CODE> functions, depending on whether you want the date and time in GMT or your local time zone.</P><PRECLASS="programlisting">($seconds, $minutes, $hours, $day_of_month, $month, $year, $wday, $yday, $isdst) = localtime($time);</PRE><PCLASS="para">The standard <ACLASS="indexterm"NAME="ch03-idx-1000006269-0"></A><ACLASS="indexterm"NAME="ch03-idx-1000006269-1"></A><ACLASS="indexterm"NAME="ch03-idx-1000006269-2"></A><ACLASS="indexterm"NAME="ch03-idx-1000006269-3"></A>Time::timelocal and Time::gmtime modules override the <CODECLASS="literal">localtime</CODE> and <CODECLASS="literal">gmtime</CODE> functions to provide named access to the individual values.</P><PRECLASS="programlisting">use Time::localtime; # or Time::gmtime$tm = localtime($TIME); # or gmtime($TIME)$seconds = $tm->sec;# ...</PRE></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-254">Discussion</A></H3><PCLASS="para">The <CODECLASS="literal">localtime</CODE> and <CODECLASS="literal">gmtime</CODE> functions return strange year and month values; the year has 1900 subtracted from it, and 0 is the month value for January. Be sure to correct the base values for year and month, as this example does:</P><PRECLASS="programlisting">($seconds, $minutes, $hours, $day_of_month, $month, $year, $wday, $yday, $isdst) = localtime($time);printf("Dateline: %02d:%02d:%02d-%04d/%02d/%02d\n", $hours, $minutes, $seconds, $year+1900, $month+1, $day_of_month);</PRE><PCLASS="para">We could have used the Time::localtime module to avoid the temporary variables:</P><PRECLASS="programlisting">use Time::localtime;$tm = localtime($time);printf("Dateline: %02d:%02d:%02d-%04d/%02d/%02d\n", $tm->hour, $tm->min, $tm->sec, $tm->year+1900, $tm->mon+1, $tm->mday);</PRE></DIV><DIVCLASS="sect2"><H3CLASS="sect2"><ACLASS="title"NAME="ch03-pgfId-282">See Also</A></H3><PCLASS="para">The <ACLASS="indexterm"NAME="ch03-idx-1000006271-0"></A><ACLASS="indexterm"NAME="ch03-idx-1000006271-1"></A><ACLASS="indexterm"NAME="ch03-idx-1000006271-2"></A><ACLASS="indexterm"NAME="ch03-idx-1000006271-3"></A><CODECLASS="literal">localtime</CODE> function 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 and Time::gmtime modules; convert in the other direction using <ACLASS="xref"HREF="ch03_03.htm"TITLE="Converting DMYHMS to Epoch Seconds">Recipe 3.2</A> <ACLASS="indexterm"NAME="ch03-idx-1000006264-0"></A><ACLASS="indexterm"NAME="ch03-idx-1000006264-1"></A><ACLASS="indexterm"NAME="ch03-idx-1000006264-2"></A><ACLASS="indexterm"NAME="ch03-idx-1000006264-3"></A></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_03.htm"TITLE="3.2. Converting DMYHMS to Epoch Seconds"><IMGSRC="../gifs/txtpreva.gif"ALT="Previous: 3.2. Converting DMYHMS to Epoch Seconds"BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="228"><ACLASS="book"HREF="index.htm"TITLE="Perl Cookbook"><IMGSRC="../gifs/txthome.gif"ALT="Perl Cookbook"BORDER="0"></A></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="228"><ACLASS="sect1"HREF="ch03_05.htm"TITLE="3.4. Adding to or Subtracting from a Date"><IMGSRC="../gifs/txtnexta.gif"ALT="Next: 3.4. Adding to or Subtracting from a Date"BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="228">3.2. Converting DMYHMS to Epoch Seconds</TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="228"><ACLASS="index"HREF="index/index.htm"TITLE="Book Index"><IMGSRC="../gifs/index.gif"ALT="Book Index"BORDER="0"></A></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="228">3.4. 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