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<section>
<h1 id="usage">
USAGE
</h1>
<pre><code>reldate [OPTIONS] [TIME_DESCRPTION]</code></pre>
<h2 id="description">
DESCRIPTION
</h2>
<p>
reldate is a small command line utility which returns the relative date
in YYYY-MM-DD format. This is helpful when scripting various time
relationships. The difference in time returned are determined by the
time increments provided.
</p>
<p>
Time increments are a positive or negative integer. Time unit can be
either day(s), week(s), month(s), or year(s). Weekday names are case
insentive (e.g. Monday and monday). They can be abbreviated to the first
three letters of the name, e.g. Sunday can be Sun, Monday can be Mon,
Tuesday can be Tue, Wednesday can be Wed, Thursday can be Thu, Friday
can be Fri or Saturday can be Sat.
</p>
<h2 id="options">
OPTIONS
</h2>
<p>
Below are a set of options available.
</p>
<pre><code>    -e, -end-of-month    Display the end of month day. E.g. 2012-02-29
    -examples            display example(s)
    -f, -from            Date the relative time is calculated from.
    -generate-manpage    generate man page
    -generate-markdown   generate markdown documentation
    -h, -help            display help
    -l, -license         display license
    -nl, -newline        if true add a trailing newline
    -quiet               suppress error messages
    -v, -version         display version</code></pre>
<h2 id="examples">
EXAMPLES
</h2>
<p>
If today was 2014-08-03 and you wanted the date three days in the past
try–
</p>
<pre><code>reldate 3 days</code></pre>
<p>
The output would be
</p>
<pre><code>2014-08-06</code></pre>
<p>
TIME UNITS
</p>
<p>
Supported time units are
</p>
<ul>
<li>
day(s)
</li>
<li>
week(s)
</li>
<li>
year(s)
</li>
</ul>
<p>
Specifying a date to calucate from
</p>
<p>
reldate handles dates in the YYYY-MM-DD format (e.g. March 1, 2014 would
be 2014-03-01). By default reldate uses today as the date to calculate
relative time from. If you use the –from option you can it will
calculate the relative date from that specific date.
</p>
<p>
reldate –from=2014-08-03 3 days
</p>
<p>
Will yield
</p>
<pre><code>2014-08-06</code></pre>
<p>
NEGATIVE INCREMENTS
</p>
<p>
Command line arguments traditionally start with a dash which we also use
to denote a nagative number. To tell the command line process that to
not treat negative numbers as an “option” precede your time increment
and time unit with a double dash.
</p>
<pre><code>reldate --from=2014-08-03 -- -3 days</code></pre>
<p>
Will yield
</p>
<pre><code>2014-07-31</code></pre>
<p>
RELATIVE WEEK DAYS
</p>
<p>
You can calculate a date from a weekday name (e.g. Saturday, Monday,
Tuesday) knowning a day (e.g. 2015-02-10 or the current date of the
week) occurring in a week. A common case would be wanting to figure out
the Monday date of a week containing 2015-02-10. The week is presumed to
start on Sunday (i.e. 0) and finish with Saturday (e.g. 6).
</p>
<pre><code>reldate --from=2015-02-10 Monday</code></pre>
<p>
will yield
</p>
<pre><code>2015-02-09</code></pre>
<p>
As that is the Monday of the week containing 2015-02-10. Weekday names
case insensitive and can be the first three letters of the English names
or full English names (e.g. Monday, monday, Mon, mon).
</p>
<p>
reldate v0.0.25
</p>
</section>

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