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>8.1. Date/Time/Calendars</H1
><P
>There is one command to change both the date and time on a <SPAN
CLASS="PRODUCTNAME"
>UNIX</SPAN
> like system, <EM
>date</EM
>, there is also a simple calendar utility, <EM
>cal</EM
>. If you are looking to change the timestamps on files please see <A
HREF="finding-information.html"
>Chapter 8</A
></P
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><DL
><DT
>date</DT
><DD
><P
>Tells you the date (and the time) and is also used to set the date/time.</P
><P
>To set the date, type<EM
> date MM:DD:YYYY </EM
>(American style date) where MM is month, DD is the number of days within the month and YYYY is the year.</P
><P
>For example to set the date to the 1st January 2000 you would type:</P
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>date 01:01:2000</PRE
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><P
>To set the time (where the <EM
>-s</EM
> option is to set a new time), type:</P
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>date<EM
> </EM
>-s hh:mm:ss</PRE
></FONT
></TD
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><P
>Another useful option you can use is <EM
>--date=&#8220;string&#8221;</EM
> (or <EM
>-d</EM
> <EM
>&#8220;string&#8221;</EM
>) option to display a date from x days ago or in x days (or x weeks, months, years et cetera). See the examples below. </P
><P
>Examples:</P
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>date --date="3 months 1 day ago"</PRE
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><P
>Will print the date 3 months and 1 day ago from the current date. Note that <EM
>--date=&#8221;x month x day ago&#8221;</EM
> and<EM
> -d &#8220;x month x day ago&#8221;</EM
> are equivalent.</P
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>date -d "3 days"</PRE
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><P
>The above command will print the date 3 days in the future from now.</P
></DD
><DT
>cal</DT
><DD
><P
>Typing <EM
>cal</EM
> will give you the calendar of the present month on your screen, in the nice standard calendar format. There are various options to customise the calendar, refer to the info/man page.</P
><P
>Example:</P
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>cal -y year</PRE
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><P
>Will display a calendar for a specific year, simply use cal -y to print the calendar for the current year.</P
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>cal 2 2004</PRE
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><P
>This will display the calendar for February 2004</P
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