<?xml version="1.0" encoding="utf-8" ?> <!-- for emacs: -*- coding: utf-8 -*- -->
<!-- Apache may like this line in the file .htaccess: AddCharset utf-8 .html -->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0 plus SVG 1.1//EN" "http://www.w3.org/2002/04/xhtml-math-svg/xhtml-math-svg-flat.dtd" >
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head><title>alarm -- set an alarm</title>
<link rel="stylesheet" type="text/css" href="../../../../Macaulay2/Style/doc.css"/>
</head>
<body>
<table class="buttons">
<tr>
<td><div><a href="_current__Directory.html">next</a> | <a href="_top_splevel_sploop.html">previous</a> | <a href="_current__Directory.html">forward</a> | <a href="_top_splevel_sploop.html">backward</a> | <a href="_system_spfacilities.html">up</a> | <a href="index.html">top</a> | <a href="master.html">index</a> | <a href="toc.html">toc</a> | <a href="http://www.math.uiuc.edu/Macaulay2/">Macaulay2 web site</a></div>
</td>
</tr>
</table>
<div><a href="index.html" title="">Macaulay2Doc</a> > <a href="___The_sp__Macaulay2_splanguage.html" title="">The Macaulay2 language</a> > <a href="_system_spfacilities.html" title="">system facilities</a> > <a href="_alarm.html" title="set an alarm">alarm</a></div>
<hr/>
<div><h1>alarm -- set an alarm</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>alarm n</tt></div>
</dd></dl>
</div>
</li>
<li><div class="single">Inputs:<ul><li><span><tt>n</tt>, <span>an <a href="___Z__Z.html">integer</a></span></span></li>
</ul>
</div>
</li>
<li><div class="single">Consequences:<ul><li>the alarm will be sounded after <tt>n</tt> seconds; it can be intercepted with <a href="_try.html" title="catch an error">try</a></li>
</ul>
</div>
</li>
</ul>
</div>
<div class="single"><h2>Description</h2>
<div>If <tt>n</tt> is zero, then no alarm is scheduled, and any previously scheduled alarm is cancelled. Any pending alarm will be cancelled when any other error occurs, or when the top level loop offers an input prompt to the user.<p/>
The value returned is the number of seconds remaining until any previously scheduled alarm was due to be delivered, or zero if there was no previously scheduled alarm.<p/>
This command may interfere with <a href="_time.html" title="time a computation">time</a> or <a href="_sleep.html" title="sleep for a while">sleep</a> on some systems.</div>
</div>
</div>
</body>
</html>
