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<!-- Common Lisp HyperSpec (TM), version 7.0 generated by Kent M. Pitman on Mon, 11-Apr-2005 2:31am EDT -->
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<TITLE>CLHS: Function DECODE-UNIVERSAL-TIME</TITLE>
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<A NAME="decode-universal-time"><I>Function</I> <B>DECODE-UNIVERSAL-TIME</B></A> <P>
<P><B>Syntax:</B><P>
<P>
<B>decode-universal-time</B> <I>universal-time <TT>&amp;optional</TT> time-zone</I><P> =&gt; <I>second, minute, hour, date, month, year, day, daylight-p, zone</I><P>
<P>
<P><B>Arguments and Values:</B><P>
<P>
<I>universal-time</I>---a <A REL=DEFINITION HREF="26_glo_u.htm#universal_time"><I>universal time</I></A>. <P>
<I>time-zone</I>---a <A REL=DEFINITION HREF="26_glo_t.htm#time_zone"><I>time zone</I></A>. <P>
<I>second</I>, <I>minute</I>, <I>hour</I>, <I>date</I>, <I>month</I>, <I>year</I>, <I>day</I>, <I>daylight-p</I>, <I>zone</I>---a <A REL=DEFINITION HREF="26_glo_d.htm#decoded_time"><I>decoded time</I></A>. <P>
<P><B>Description:</B><P>
<P>
Returns the <A REL=DEFINITION HREF="26_glo_d.htm#decoded_time"><I>decoded time</I></A> represented by the given <A REL=DEFINITION HREF="26_glo_u.htm#universal_time"><I>universal time</I></A>. <P>
If <I>time-zone</I> is not supplied, it defaults to the current time zone adjusted for daylight saving time. If <I>time-zone</I> is supplied, daylight saving time information is ignored. The daylight saving time flag is <A REL=DEFINITION HREF="a_nil.htm#nil"><B>nil</B></A> if <I>time-zone</I> is supplied. <P>
<P><B>Examples:</B><P>
<P>
<PRE>
(decode-universal-time 0 0) =&gt; 0, 0, 0, 1, 1, 1900, 0, <A REL=DEFINITION HREF="26_glo_f.htm#false">false</A>, 0
;; The next two examples assume Eastern Daylight Time.
(decode-universal-time 2414296800 5) =&gt; 0, 0, 1, 4, 7, 1976, 6, <A REL=DEFINITION HREF="26_glo_f.htm#false">false</A>, 5
(decode-universal-time 2414293200) =&gt; 0, 0, 1, 4, 7, 1976, 6, <A REL=DEFINITION HREF="26_glo_t.htm#true">true</A>, 5
;; This example assumes that the time zone is Eastern Daylight Time
;; (and that the time zone is constant throughout the example).
(let* ((here (nth 8 (multiple-value-list (get-decoded-time)))) ;Time zone
(recently (get-universal-time))
(a (nthcdr 7 (multiple-value-list (decode-universal-time recently))))
(b (nthcdr 7 (multiple-value-list (decode-universal-time recently here)))))
(list a b (equal a b))) =&gt; ((T 5) (NIL 5) NIL)
</PRE>
</TT> <P>
<P><B>Affected By:</B><P>
<P>
<A REL=DEFINITION HREF="26_glo_i.htm#implementation-dependent"><I>Implementation-dependent</I></A> mechanisms for calculating when or if daylight savings time is in effect for any given session. <P>
<P><B>Exceptional Situations:</B> None.
<P>
<P><B>See Also:</B><P>
<P>
<A REL=DEFINITION HREF="f_encode.htm#encode-universal-time"><B>encode-universal-time</B></A>, <A REL=DEFINITION HREF="f_get_un.htm#get-universal-time"><B>get-universal-time</B></A>, <A REL=CHILD HREF="25_ad.htm">Section 25.1.4 (Time)</A> <P>
<P><B>Notes:</B> None.
<P>
<P><HR>The following <A REL=META HREF="../Front/X3J13Iss.htm">X3J13 cleanup issues</A>, <I>not part of the specification</I>, apply to this section:<P><UL><LI> <A REL=CHILD HREF="../Issues/iss098.htm">DECODE-UNIVERSAL-TIME-DAYLIGHT:LIKE-ENCODE</A><LI> <A REL=CHILD HREF="../Issues/iss348.htm">TIME-ZONE-NON-INTEGER:ALLOW</A><P></UL><HR>
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