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diff --git a/help/en/bash/date.html b/help/en/bash/date.html new file mode 100644 index 0000000..8a56d9a --- /dev/null +++ b/help/en/bash/date.html @@ -0,0 +1,318 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> +<head> +<link rel="STYLESHEET" href="../term_tools/main.css" type="text/css"> +<title>date MAN Page</title> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +</head><body><!-- #BeginLibraryItem "/Library/head_bash.lbi" --><div id="nav-menu"> +<ul> +<li><a class="rl" href="../term_tools/index.html"><img src="../term_tools/images/ss64.gif" title="Home" alt="Home"></a></li> +<li><a class="rl" href="../term_tools/bash"><img src="../term_tools/images/bash-l.gif" title="bash" alt="bash"></a></li> +<li><!-- Search Google --> +<form action="http://www.google.com/search" method="get" style="margin:0px;padding:0px;"> +<div align="right"> +<input name="q" type="text" class="body" size="25"> +<input class="submit" type="submit" value="Search"> +<input type="hidden" name="q" value="site:ss64.com/bash/"> +</div> +</form></li> +<li><a class="rr" href="syntax.html"><img src="../term_tools/images/syntax-r.gif" title="Bash Syntax"></a></li> +</ul> +</div> <!-- #EndLibraryItem --><h1> date</h1> +<p>Display or change the date.</p> +<pre>Syntax + date [<i>option</i>]... [+<i>Format</i>] + + date [<i>option</i>] [MMDDhhmm[[CC]YY][.ss]] +</pre> +<p>`date' with no arguments prints the current time and date, in the +format of the <span class="code">%c</span> directive (described below).<br> +<br> +If given an argument that starts with a <span class="code">+</span>, <span class="code">date</span> prints the +current time and date (or the time and date specified by the<span class="code"> --date</span> option, see below) in the format defined by that argument, which is the +same as in the <span class="code">strftime</span> function. </p> +<p>Except for directives, which start +with <span class="code">%</span>, characters in the format string are printed unchanged. The +directives are described below.</p> +<pre> +Options: + -d, --date=<i>String</i> Display time described by <i>String</i>, instead of `now' + this can be in almost any common format. + It can contain month names, timezones, `am' and `pm', + `yesterday', `ago', `next', etc. + + -f, --file=<i>DateFile</i> like --date once for each line of <i>DateFile</i> + If <i>DateFile</i> is `-', use standard input. This is + useful when you have many dates to process, + because the system overhead of starting up the + `date' executable many times can be considerable. + + -I, --iso-8601[=<i>Timespec</i>] Output an ISO-8601 compliant date/time string., `%Y-%m-%d'. + <i>Timespec</i>=`date' (or missing) for date only, + `hours', `minutes', or `seconds' for date and + time to the indicated precision. + If showing any time terms, then include the time zone + using the format `%z'. If `--utc' is also specified, + use `%Z' in place of `%z'. + + -r, --reference=<i>File</i> Display the last modification time of <i>File</i> + + -R, --rfc-822 Output RFC-822 compliant date string + + -s, --set=<i>String</i> Set time described by <i>String</i> (see -d above) + + -u, --utc, --universal Print or set Coordinated Universal Time + + --help Display this help and exit + --version output version information and exit + </pre><p><i><a name="format"></a>Format</i> controls the output as follows. The only valid option for the second form <span class="code">(MMDDhhmm[[CC]YY][.ss])</span>will specify Coordinated Universal Time. </p> +<p> Interpreted sequences are:</p> +<pre> + Date: + D Date in mm/dd/yy format (06/14/06) + x Date in standard format for locale (09/12/07 for English-US) + + Year: + C Century (20 for 2006) + Y Year in 4-digit format (2006) + y Year in 2-digit format (06) + G Same as 'Y' + g Same as 'y' + + Month: + b Month name - abbreviated (Jan) + B Month name - full (January) + h Same as 'b' + m Month number (06) + + Week: + W Week of the year (00-52) + V Week of the year (01-53) + U Same as 'W' + + Day: + a Day of the week - abbreviated name (Mon) + A Day of the week - full name (Monday) + u Day of the week - number (Monday = 1) + d Day of the month - 2 digits (05) + e Day of the month - digit preceded by a space ( 5) + j Day of the year - (1-366) + w Same as 'u' + + Time: + p AM or PM + r Time in 12-hour format (09:15:36 AM) + R Time in 24-hour format - no seconds (17:45) + T Time in 24 hour format (17:45:52) + X Same as 'T' + Z Time zone offset from UTC (-07) + + Hour: + H Hour in 24-hour format (17) + I Hour in 12 hour format (05) + k Same as 'H' + l Same as 'I' (Upper-case I = Lower-case L) + + Minutes & Seconds: + M Minutes (35) + S Seconds (05) + s Seconds elapsed since January 1, 1970 00:00:00 (1150451174.95705) +</pre> +<p>Here are the same format codes in alphabetical order:</p> +<pre> + %% a literal % + %a locale's abbreviated weekday name (Sun..Sat) + %A locale's full weekday name, variable length (Sunday..Saturday) + %b locale's abbreviated month name (Jan..Dec) + %B locale's full month name, variable length (January..December) + %c locale's date and time (Sat Nov 04 12:02:33 EST 1989) + %d day of month (01..31) + %D date (mm/dd/yy) + %e day of month, blank padded ( 1..31) + %h same as %b, locale's abbreviated month name (Jan..Dec) + %H hour :24 hour(00..23) + %I hour :12 hour(01..12) + %j day of year (001..366) + %k hour :24 hour(00..23) + %l hour :12 hour(01..12) + %m month (01..12) + %M minute (00..59) + %n a newline + %p locale's AM or PM + %r time, 12-hour (hh:mm:ss [AP]M) + %s seconds since 00:00:00, Jan 1, 1970 (a GNU extension) + Note that this value is defined by the localtime system + call. It isn't changed by the `--date' option. + %S second (00..60) + %t a horizontal tab + %T time, 24-hour (hh:mm:ss) + %U week number of year with Sunday as first day of week (00..53) + %V week number of year with Monday as first day of week (01..53) + If the week containing January 1 has four or + more days in the new year, then it is considered week 1; + otherwise, it is week 53 of the previous year, and the next week + is week 1. (See the ISO 8601: 1988 standard.) + + %w day of week (0..6); 0 represents Sunday + %W week number of year with Monday as first day of week (00..53) + %x locale's date representation (mm/dd/yy) + %X locale's time representation (%H:%M:%S) + %y last two digits of year (00..99) + %Y year (1970...) + %z RFC-822 style numeric timezone (-0500) (a nonstandard extension) + This value reflects the _current_ time zone. + It isn't changed by the `--date' option. + %Z time zone (e.g., EDT), or nothing if no time zone is determinable + This value reflects the _current_ time zone. + It isn't changed by the `--date' option. +</pre> +<p>By default, date pads numeric fields with zeroes. GNU date recognizes +the following modifiers between <span class="code">%</span> and a numeric directive.<br> +<br> +<span class="code">-</span> (hyphen) do not pad the field; useful if the output is intended for +human consumption.<br> + +<span class="code">_</span> (underscore) pad the field with spaces; useful if you need a fixed +number of characters in the output, but zeroes are too distracting.</p> +<p>The - and _ are GNU extensions. +Here is an example illustrating the differences:</p> +<pre> + date +%d/%m -d "Feb 1" + => 01/02 + date +%-d/%-m -d "Feb 1" + => 1/2 + date +%_d/%_m -d "Feb 1" + => 1/ 2 +</pre> +<p>Setting the time</p> +<p>If given an argument that does not start with <span class="code">+</span>, <span class="code">date</span> sets the +system clock to the time and date specified by that argument (as +described below). You must have appropriate privileges to set the +system clock. The <span class="code">--date</span> and <span class="code">--set</span> options may not be used with +such an argument. The <span class="code">--universal</span> option may be used with such an +argument to indicate that the specified time and date are relative to +Coordinated Universal Time rather than to the local time zone.<br> +<br> +The argument must consist entirely of digits, which have the +following meaning:</p> +<pre> MM month + DD day within month + HH hour + MM minute + CC first two digits of year (optional) + YY last two digits of year (optional) + SS second (optional) + + The `--set' option also sets the system clock; see the examples below.</pre> +<p><b>Examples</b><br> +<br> +Print the date of the day before yesterday:<br> + <span class="code">$ date --date='2 days ago'</span><br> +<br> +Rename a file with the current date and time <br> +<span class="code">$ STAMPME=$HOME/demo_file_$(date +%Y%m%d-%H%M).txt<br> +$ mv $HOME/demo_file</span> <span class="code">$STAMPME</span><br> +<br> +Print the date of the day three months and one day hence:<br> +<span class="code">$ date --date='3 months 1 day'</span><br> +<br> +Print the day of year of Christmas in the current year:<br> +<span class="code">$ date --date='25 Dec' +%j</span><br> +<br> +Print the current full month name and the day of the month:<br> +<span class="code">$ date '+%B %d'</span><br> +<br> +But this may not be what you want because for the first nine days +of the month, the `%d' expands to a zero-padded two-digit field, +for example <span class="code">date -d 1may '+%B %d'</span> will print `May 01'.<br> +<br> +* Print a date without the leading zero for one-digit days of the +month, you can use the (GNU extension) `-' modifier to suppress +the padding altogether.<br> +<span class="code">$ date -d=1may '+%B %-d'</span><br> +<br> +Print the current date and time in the format required by many +non-GNU versions of `date' when setting the system clock:<br> +<span class="code">$ date +%m%d%H%M%Y.%S</span><br> +<br> +Set the system date and time<br> +<span class="code">$ date --set="2002-6-29 11:59 AM" </span><br> +<br> +Set the system clock forward by two minutes:<br> +<span class="code">$ date --set='+2 minutes'</span><br> +<br> +Print the date in the format specified by RFC-822, use <span class="code">date +--rfc</span><br> +I just did and saw this:<br> + +Mon, 25 Mar 1996 23:34:17 -0600<br> +<br> +To convert a date string to the number of seconds since the epoch +(which is 1970-01-01 00:00:00 UTC), use the `--date' option with +the `%s' format. That can be useful in sorting and/or graphing +and/or comparing data by date. The following command outputs the +number of the seconds since the epoch for the time one second later +than the epoch, but in time zone five hours later (Cambridge, +Massachusetts), thus a total of five hours and one second after +the epoch:<br> +<br> +<span class="code">$ date --date='1970-01-01 00:00:01 UTC +5 hours' +%s<br> +18001</span><br> +<br> +Suppose you had _not_ specified time zone information in the +example above. Then, date would have used your computer's idea of<br> +the time zone when interpreting the string. Here's what you would +get if you were in Greenwich, England:<br> +<br> +# local time zone used<br> +<span class="code">$ date --date='1970-01-01 00:00:01' +%s<br> +1</span><br> +<br> + If you're sorting or graphing dated data, your raw date values may +be represented as seconds since the epoch. But few people can<br> +look at the date `946684800' and casually note "Oh, that's the +first second of the year 2000."<br> +<br> +<span class="code">$ date --date='2000-01-01 UTC' +%s<br> +946684800</span><br> +<br> +To convert such an unwieldy number of seconds back to a more +readable form, use a command like this:<br> +<br> +<span class="code">$ date -d '1970-01-01 946684800 sec' +"%Y-%m-%d %T %z"<br> +2000-01-01 00:00:00 +0000</span><br> +</p> +<p><b> </b><i>"Carpe Diem - Seize the day" - Horace + </i><br> + <b><br> + Related</b>:<br> + <br> + <a href="cal.html">cal</a> - Display a calendar<br> + <a href="crontab.html">crontab</a> - Schedule a command to run at a later time<br> + <a href="time.html">time</a> - Measure Program Resource Use<br> + <a href="times.html">times</a> - User and system times <br> + <a href="touch.html">touch</a> - Change file timestamps <br> +Equivalent Windows command: <a href="../term_tools/nt/date.html">DATE</a> - Display or set the date</p> +<!-- #BeginLibraryItem "/Library/foot_bash.lbi" --><p align="left"><script type="text/javascript"><!-- +google_ad_client = "pub-6140977852749469"; +google_ad_width = 300; +google_ad_height = 250; +google_ad_format = "300x250_as"; +google_ad_type = "text_image"; +google_ad_channel ="1984328893"; +google_color_border = "CCCCCC"; +google_color_bg = "CCCCCC"; +google_color_link = "000000"; +google_color_text = "333333"; +google_color_url = "0000FF"; +//--></script> +<script type="text/javascript" + src="http://pagead2.googlesyndication.com/pagead/show_ads.js"> +</script><br> +</p> +<div align="center"><hr size="1"> + <p id="top"><a href="#"><img src="../term_tools/images/top-4.gif" width="47" height="53" border="0" alt="Back to the Top" title="Back to the Top"></a></p> + <p class="tagline">© Copyright <a href="http://ss64.com/">SS64.com</a> 1999-2010<br> +Some rights reserved<br> +</p> +</div><!-- #EndLibraryItem --></body> +</html> |