[mirrors/Programs.git] / bash / bashcrawl / test.html



<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>

	<title>Using arrays in bash</title>

	<meta name="description" content="Learn two ways two declare an array in bash in this Linux tip." />
	<meta name="keywords" content="Linux,Vincent Danen,Foo,Linux Tips Newsletter" />

	<style type="text/css" media="screen">
    	@import url("http://i.techrepublic.com.com/css/tr2006.css");
		@import url("http://i.techrepublic.com.com/css/tr_ws2006.css");
		@import url("http://news.zdnet.com/css/z/ads/hs.css");
		@import url("http://i.techrepublic.com.com/css/trArticle.css");
	</style>
	
	<link rel="stylesheet" type="text/css" media="print" href="http://i.techrepublic.com.com/css/trArticlePrint.css">
	<link REL="SHORTCUT ICON" HREF="http://techrepublic.com.com/images/favicon.ico">
	<script type="text/javascript" SRC="http://i.techrepublic.com.com/js/articleScript.js"></script>
	<script type="text/javascript">var dwInfo = "&oid=2100-10878_11-5820685&ptId=2100&onId=10878&sId=11&asId=5820685";</script>
	<!-- MAC ad --><!-- NO AD TEXT: _QUERY_STRING="sp=80&pos=100" _REQ_NUM="0"  --><!-- default ad --><IMG SRC="http://adlog.com.com/adlog/i/r=7007&s=501815&o=1035:&h=cn&p=2&b=9&l=en_US&site=11&pt=5100&nd=1035&pid=&cid=5820685&pp=100&e=87&rqid=00c17-ad-e5477C00C37AAE066&orh=www.google.com&ort=&oepartner=&epartner=&cpnmodule=&count=&ra=213.220.241.158&dvar=&ucat_rsi=&t=2008.01.14.02.23.42/http://i.i.com.com/cnwk.1d/Ads/common/dotclear.gif" HEIGHT="0" WIDTH="0" alt="" style="position:absolute; top:0px; left:0px" /><!-- MAC [r20071210-1033-DynamicVars:1.13.8] c13-b2b-publish-web2.cnet.com::39603120 2008.01.14.02.23.42 --><!-- MAC T 689.689.68B.68B -->

</head>
<body id="EyeBrow">

<div id="goiter">

	<div id="width">
<div id="eyebrowsBanner">
		<div id="eyebrowsInner">
			<!-- MAC ad --><div class="rubics_netxp1_main">
	On CHOW: 
	<a target="_top" href="http://dw.com.com/rubicsclk?ver=2&ts=2008.01.13.18.23.44&edId=87&onId=1035&ptId=5100&sId=11&appId=19&offId=948&unitId=45&poolId=1&f1=9&f2=%2d0&f3=%2d0&alg=3&&opt=0&linkPos=1&destUrl=http:%2F%2Fwww.chow.com%2Fstories%2F10785" class="xpromolink">Ten perfect grilled cheese sandwiches</a>
	<img src="http://dw.com.com/rubicsimp/c.gif?ver=2&ts=2008.01.13.18.23.44&edId=87&onId=1035&ptId=5100&sId=11&appId=19&unitId=45&poolId=1&f1=9&f2=%2d0&f3=%2d0&alg=3&opt=0&off=948,-1" alt="" height="1" width="1"/>
</div>
<!-- ros [r20070521-1832-ronr-v1-13-5:1.13.5] c17-ad-rubics-ros4.cnet.com::3971599280 2008.01.13.18.23.44 --><!-- ros t 0.0.0.0.0.0.0.0 --><!-- MAC [r20071210-1033-DynamicVars:1.13.8] c13-b2b-publish-web2.cnet.com::39603120 2008.01.14.02.23.42 --><!-- MAC T 68B.68B.68D.68E -->
			<ul class="cnbLinks">
				<li>BNET Business Network: </li>
				<li><a href="http://www.bnet.com">BNET</a> |</li>
				<li><a href="http://techrepublic.com.com">TechRepublic</a> |</li>
				<li><a href="http://www.zdnet.com">ZDNet</a></li>
			</ul>
		</div><!-- /eyebrowsInner -->
	</div><!-- /eyebrowsBanner -->
				<div id="masthead">
		<a id="logo" href="http://techrepublic.com.com"></a>

		
			<ul class="tool">
				<li><a href="/5265-11518-0.html" class="blue">My Workspace</a>&nbsp;|&nbsp;<a href="http://nl.com.com/acct_mgmt.sc?brand=techrepublic" class="blue">My Newsletters</a></li>
				 <li><a href="/1320-4-55.html?path=/5213-6257-0.html" class="orange normal">Log in</a>&nbsp;|&nbsp;<a href="/1301-4-55.html?path=/5213-6257-0.html" class="orange normal">Get a free membership</a></li>
			</ul>

		  
	</div><!-- /masthead -->


<div id="main">
	<ul id="headerNav">
	   <li><a href="http://techrepublic.com.com/">Home</a></li>   
	   <li><a href="http://blogs.techrepublic.com.com/">Blogs</a></li>
	   <li><a href="http://downloads.techrepublic.com.com/">Downloads</a></li>
	   <li><a href="http://techrepublic.com.com/5221-6230-0.html">Forums</a></li>
	   <li><a class="on" href="http://techrepublic.com.com/2001-10875-0.html">Articles</a></li>
		<li><a href="http://content.techrepublic.com.com/2350-1_11-0.html">Photos</a></li>
	   <li><a  href="http://video.techrepublic.com.com/2434-13789_11-167680.html">Videos</a></li>
		<li><a href="http://webcasts.techrepublic.com.com">Webcasts</a></li> 
	   <li><a href="http://whitepapers.techrepublic.com.com/">White Papers</a></li>
	   <li><a href="http://software.techrepublic.com.com">Software</a></li>
	   <li><a href="http://jobs.techrepublic.com.com/">Jobs</a></li>
		
		<li><a href="http://techrepublic.com.com/1393-6242-97.html">Store</a></li>
   		 
	</ul>
	
	<div id="topHTML">
		<form  action="http://search.techrepublic.com.com/index.php" method="get" name="tr_site_search" id="searchForm"  class="articleForm">

			<input id="searchInput" name="q" type="text" value="Search" onFocus="this.value=''" />
			<select id="searchList" name="t">
										<option value="11">in Articles</option>
		   							<option value="0">all of TechRepublic</option>
			</select>
			<input id="searchButton" name="go" value="Search" type="submit" />
			
		</form>
	</div><!--/topHTML-->

	<div id="content" class="clearFix">
		<div id="leftCol">
			<div id="contentHeader">
				<h1>Using arrays in bash</h1>
				<p class="byline">by <a href="http://search.techrepublic.com.com/search/Vincent Danen.html">Vincent Danen</a>&nbsp;|&nbsp;Aug 08, 2005 7:00:00 AM</p>

							<p class="tags"><b>Tags:</b> 										<a href="http://search.techrepublic.com.com/search/Linux.html">Linux</a>, 										<a href="http://search.techrepublic.com.com/search/Vincent Danen.html">Vincent Danen</a>, 										<a href="http://search.techrepublic.com.com/search/Foo.html">Foo</a>, 										<a href="http://search.techrepublic.com.com/search/Linux Tips Newsletter.html">Linux Tips Newsletter</a>									</p>
			

				<div class="interact fadeBtmLeft clearFix">
					<div class="cmntCount">
					   <a href="#comments"><span>


   	4
  

</span> comment(s)</a>
					</div>
					<ul class="toolbar">
						

<li class="share"><a title="Email this to a friend" href="javascript:usrActionReg(this,19);">Email</a></li>

<li class="save"><a title="Save this to my Workspace" href="http://techrepublic.com.com/5262-6257-0.html?link=http%3A%2F%2Farticles.techrepublic.com.com%2F5100-1035_11-5820685.html%3Fpart%3Drss%26tag%3Dfeed%26subj%3Dtr&title=Using+arrays+in+bash&path=http%3A%2F%2Farticles.techrepublic.com.com%2F5100-1035_11-5820685.html%3Fpart%3Drss%26tag%3Dfeed%26subj%3Dtr">Save</a></li>
		<li class="print"><a title="Printer-friendly version" href="javascript:usrActionReg(this,20);">Print</a></li>
	<li class="digg"><a href="http://digg.com/submit?phase=2&url=http://articles.techrepublic.com.com/5100-1035_11-5820685.html&title=Using+arrays+in+bash&bodytext=Learn+two+ways+two+declare+an+array+in+bash+in+this+Linux+tip.&topic=tech_news" class="last">Digg This</a></li>
						

         <li class="recommend"><a href="http://articles.techrepublic.com.com/1320-4-55.html?path=http://articles.techrepublic.com.com/5100-10878_11-5820685.html" TITLE="Click to recommend" class="last"></a></li>
   
   <li class="vote"><div id="votecount" class="votecount" TITLE="How many people recommended this item">1 </div></li>

<script language="JavaScript">
        var http = createRequestObject();
        var existing_votes = '';

        function createRequestObject()
        {
            var ro;
            var browser = navigator.appName;
            if(browser == "Microsoft Internet Explorer"){
                ro = new ActiveXObject("Microsoft.XMLHTTP");
            }else{
                ro = new XMLHttpRequest();
            }
            return ro;
        }

        function Set_Cookie(name, value, expires, path)
        {
            // set time, it's in milliseconds
            var today = new Date();
            today.setTime( today.getTime() );

            expires = expires * 1000 * 60 * 60 * 24;
            var expires_date = new Date( today.getTime() + (expires) );

            document.cookie = name + "=" + escape( value ) +  ";expires=" + expires_date.toGMTString() + ";path=" + path;

        }

        function sendVote()
        {
            http.open('get', '');
            http.onreadystatechange = handleResponse;
            http.send(null);
        }

        function handleResponse()
        {
            if(http.readyState == 4)
            {
                var response = http.responseText;
                var temp_array = new Array();
                temp_array = response.split('~');
                var ranking = temp_array[0];

                if (ranking > 0) {
                   ranking = ranking;
                }

				// Replace with ajax magic
                document.getElementById('votecount').innerHTML = ranking;

                // Remove the thumbs
                var voter = document.getElementById('recommend');
                voter.className = "thanks";
                voter.innerHTML = "";

                Set_Cookie('service',(existing_votes + '~85140'),30,'/');
            }
        }
</script>


					</ul><!-- /toolbar -->
				</div><!-- /interact -->
			</div><!-- /contentHeader -->

			<div id="articleText">
				<p class="takeaway"><b>Takeaway:</b> Learn two ways two declare an array in bash in this Linux tip.</p>

								   <div class="related">
				   <div class="relatedBg">
				     			<!--Medusa Related Content-->
				        		        			<script type="text/javascript" src="http://service.techrepublic.com.com/wi?spot=related-js&format=text&count=5&null=true&id=TR.TA.1.5820685&referer=http%3A%2F%2Fwww.google.com%2Fsearch%3Fhl%3Dcs%26client%3Diceweasel-a%26rls%3Dorg.debian%253Acs-CZ%253Aunofficial%26q%3Dbash%2Barray%26btnG%3DHledat%26lr%3D"></script>
                					<script type="text/javascript">getrelatedContent()</script>		
			<!--/Medusa Related Content-->
										</div><!--relatedBg-->
					</div><!-- /related -->
				
				<p>Assigning variables in bash is easily done and extremely\r
useful, but like other programming languages, bash can also use arrays. This is\r
particularly handy when you want to read the contents of a file into an array or\r
simply keep your scripts more organized and logical.</p>\r
\r
<p>There are two ways of declaring an array:</p>\r
\r
<pre>&lt;code&gt;<br>declare -a FOO<br>&lt;/code&gt;</pre>\r
\r
<p>This creates an empty array called FOO. You can also declare\r
an array by assigning values to it:</p>\r
\r
<pre>&lt;code&gt;<br>FOO[2] = 'bar'<br>&lt;/codE&gt;</pre>\r
\r
<p>This assigns the third element of the array to the value\r
'bar'. In this instance, FOO[0] and FOO[1] are also\r
created, but their values are empty.</p>\r
\r
<p>To populate an array, use:</p>\r
\r
<pre>&lt;code&gt;<br>FOO=( bar string 'some text' )<br>&lt;/code&gt;</pre>\r
\r
<p>This assigns the first element (FOO[0])\r
to 'bar', the second (FOO[1]) to 'string' and the final element (FOO[3]) to\r
'some text'. Notice that the array elements are separated by a blank space, so\r
if a value contains white spaces it must be quoted.</p>\r
\r
<p>To use an array, it is referred to as $FOO[2]\r
but it also needs to be surrounded in curly braces, otherwise bash will not\r
expand it correctly:</p>\r
\r
<pre>&lt;code&gt;<br>$ echo {$FOO[2]}<br>some text<br>&lt;/code&gt;</pre>\r
\r
<p>To loop through an array, you can use a piece of shell code\r
like the following:</p>\r
\r
<pre>&lt;code&gt;<br>\r
#!/bin/sh</pre><pre>FOO=( bar string 'some text')<br>foonum=${#FOO}<br>\r
Commit	Line	Data
	1
	2
	3
	4
	5
	6
	7	<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
	8	<html>
	9	<head>
	10
	11	<title>Using arrays in bash</title>
	12
	13	<meta name="description" content="Learn two ways two declare an array in bash in this Linux tip." />
	14	<meta name="keywords" content="Linux,Vincent Danen,Foo,Linux Tips Newsletter" />
	15
	16	<style type="text/css" media="screen">
	17	@import url("http://i.techrepublic.com.com/css/tr2006.css");
	18	@import url("http://i.techrepublic.com.com/css/tr_ws2006.css");
	19	@import url("http://news.zdnet.com/css/z/ads/hs.css");
	20	@import url("http://i.techrepublic.com.com/css/trArticle.css");
	21	</style>
	22
	23	<link rel="stylesheet" type="text/css" media="print" href="http://i.techrepublic.com.com/css/trArticlePrint.css">
	24	<link REL="SHORTCUT ICON" HREF="http://techrepublic.com.com/images/favicon.ico">
	25	<script type="text/javascript" SRC="http://i.techrepublic.com.com/js/articleScript.js"></script>
	26	<script type="text/javascript">var dwInfo = "&oid=2100-10878_11-5820685&ptId=2100&onId=10878&sId=11&asId=5820685";</script>
	27	<!-- MAC ad --><!-- NO AD TEXT: _QUERY_STRING="sp=80&pos=100" _REQ_NUM="0" --><!-- default ad --><IMG SRC="http://adlog.com.com/adlog/i/r=7007&s=501815&o=1035:&h=cn&p=2&b=9&l=en_US&site=11&pt=5100&nd=1035&pid=&cid=5820685&pp=100&e=87&rqid=00c17-ad-e5477C00C37AAE066&orh=www.google.com&ort=&oepartner=&epartner=&cpnmodule=&count=&ra=213.220.241.158&dvar=&ucat_rsi=&t=2008.01.14.02.23.42/http://i.i.com.com/cnwk.1d/Ads/common/dotclear.gif" HEIGHT="0" WIDTH="0" alt="" style="position:absolute; top:0px; left:0px" /><!-- MAC [r20071210-1033-DynamicVars:1.13.8] c13-b2b-publish-web2.cnet.com::39603120 2008.01.14.02.23.42 --><!-- MAC T 689.689.68B.68B -->
	28
	29	</head>
	30	<body id="EyeBrow">
	31
	32	<div id="goiter">
	33
	34	<div id="width">
	35	<div id="eyebrowsBanner">
	36	<div id="eyebrowsInner">
	37	<!-- MAC ad --><div class="rubics_netxp1_main">
	38	On CHOW:
	39	<a target="_top" href="http://dw.com.com/rubicsclk?ver=2&ts=2008.01.13.18.23.44&edId=87&onId=1035&ptId=5100&sId=11&appId=19&offId=948&unitId=45&poolId=1&f1=9&f2=%2d0&f3=%2d0&alg=3&&opt=0&linkPos=1&destUrl=http:%2F%2Fwww.chow.com%2Fstories%2F10785" class="xpromolink">Ten perfect grilled cheese sandwiches</a>
	40	<img src="http://dw.com.com/rubicsimp/c.gif?ver=2&ts=2008.01.13.18.23.44&edId=87&onId=1035&ptId=5100&sId=11&appId=19&unitId=45&poolId=1&f1=9&f2=%2d0&f3=%2d0&alg=3&opt=0&off=948,-1" alt="" height="1" width="1"/>
	41	</div>
	42	<!-- ros [r20070521-1832-ronr-v1-13-5:1.13.5] c17-ad-rubics-ros4.cnet.com::3971599280 2008.01.13.18.23.44 --><!-- ros t 0.0.0.0.0.0.0.0 --><!-- MAC [r20071210-1033-DynamicVars:1.13.8] c13-b2b-publish-web2.cnet.com::39603120 2008.01.14.02.23.42 --><!-- MAC T 68B.68B.68D.68E -->
	43	<ul class="cnbLinks">
	44	<li>BNET Business Network: </li>
	45	<li><a href="http://www.bnet.com">BNET</a> \|</li>
	46	<li><a href="http://techrepublic.com.com">TechRepublic</a> \|</li>
	47	<li><a href="http://www.zdnet.com">ZDNet</a></li>
	48	</ul>
	49	</div><!-- /eyebrowsInner -->
	50	</div><!-- /eyebrowsBanner -->
	51	<div id="masthead">
	52	<a id="logo" href="http://techrepublic.com.com"></a>
	53
	54
	55
	56	<ul class="tool">
	57	<li><a href="/5265-11518-0.html" class="blue">My Workspace</a> \| <a href="http://nl.com.com/acct_mgmt.sc?brand=techrepublic" class="blue">My Newsletters</a></li>
	58	<li><a href="/1320-4-55.html?path=/5213-6257-0.html" class="orange normal">Log in</a> \| <a href="/1301-4-55.html?path=/5213-6257-0.html" class="orange normal">Get a free membership</a></li>
	59	</ul>
	60
	61
	62
	63	</div><!-- /masthead -->
	64
	65
	66	<div id="main">
	67	<ul id="headerNav">
	68	<li><a href="http://techrepublic.com.com/">Home</a></li>
	69	<li><a href="http://blogs.techrepublic.com.com/">Blogs</a></li>
	70	<li><a href="http://downloads.techrepublic.com.com/">Downloads</a></li>
	71	<li><a href="http://techrepublic.com.com/5221-6230-0.html">Forums</a></li>
	72	<li><a class="on" href="http://techrepublic.com.com/2001-10875-0.html">Articles</a></li>
	73	<li><a href="http://content.techrepublic.com.com/2350-1_11-0.html">Photos</a></li>
	74	<li><a href="http://video.techrepublic.com.com/2434-13789_11-167680.html">Videos</a></li>
	75	<li><a href="http://webcasts.techrepublic.com.com">Webcasts</a></li>
	76	<li><a href="http://whitepapers.techrepublic.com.com/">White Papers</a></li>
	77	<li><a href="http://software.techrepublic.com.com">Software</a></li>
	78	<li><a href="http://jobs.techrepublic.com.com/">Jobs</a></li>
	79
	80	<li><a href="http://techrepublic.com.com/1393-6242-97.html">Store</a></li>
	81
	82	</ul>
	83
	84	<div id="topHTML">
	85	<form action="http://search.techrepublic.com.com/index.php" method="get" name="tr_site_search" id="searchForm" class="articleForm">
	86
	87	<input id="searchInput" name="q" type="text" value="Search" onFocus="this.value=''" />
	88	<select id="searchList" name="t">
	89	<option value="11">in Articles</option>
	90	<option value="0">all of TechRepublic</option>
	91	</select>
	92	<input id="searchButton" name="go" value="Search" type="submit" />
	93
	94	</form>
	95	</div><!--/topHTML-->
	96
	97	<div id="content" class="clearFix">
	98	<div id="leftCol">
	99	<div id="contentHeader">
	100	<h1>Using arrays in bash</h1>
	101	<p class="byline">by <a href="http://search.techrepublic.com.com/search/Vincent Danen.html">Vincent Danen</a> \| Aug 08, 2005 7:00:00 AM</p>
	102
	103	<p class="tags"><b>Tags:</b> <a href="http://search.techrepublic.com.com/search/Linux.html">Linux</a>, <a href="http://search.techrepublic.com.com/search/Vincent Danen.html">Vincent Danen</a>, <a href="http://search.techrepublic.com.com/search/Foo.html">Foo</a>, <a href="http://search.techrepublic.com.com/search/Linux Tips Newsletter.html">Linux Tips Newsletter</a> </p>
	104
	105
	106
	107
	108
	109
	110
	111
	112
	113	<div class="interact fadeBtmLeft clearFix">
	114	<div class="cmntCount">
	115	<a href="#comments"><span>
	116
	117
	118
	119
	120
	121
	122
	123
	124
	125
	126
	127
	128
	129
	130
	131
	132
	133
	134	4
	135
	136
	137
	138	</span> comment(s)</a>
	139	</div>
	140	<ul class="toolbar">
	141
	142
	143
	144	<li class="share"><a title="Email this to a friend" href="javascript:usrActionReg(this,19);">Email</a></li>
	145
	146	<li class="save"><a title="Save this to my Workspace" href="http://techrepublic.com.com/5262-6257-0.html?link=http%3A%2F%2Farticles.techrepublic.com.com%2F5100-1035_11-5820685.html%3Fpart%3Drss%26tag%3Dfeed%26subj%3Dtr&title=Using+arrays+in+bash&path=http%3A%2F%2Farticles.techrepublic.com.com%2F5100-1035_11-5820685.html%3Fpart%3Drss%26tag%3Dfeed%26subj%3Dtr">Save</a></li>
	147	<li class="print"><a title="Printer-friendly version" href="javascript:usrActionReg(this,20);">Print</a></li>
	148	<li class="digg"><a href="http://digg.com/submit?phase=2&url=http://articles.techrepublic.com.com/5100-1035_11-5820685.html&title=Using+arrays+in+bash&bodytext=Learn+two+ways+two+declare+an+array+in+bash+in+this+Linux+tip.&topic=tech_news" class="last">Digg This</a></li>
	149
	150
	151
	152
	153
	154
	155
	156
	157
	158
	159
	160
	161
	162
	163
	164
	165	<li class="recommend"><a href="http://articles.techrepublic.com.com/1320-4-55.html?path=http://articles.techrepublic.com.com/5100-10878_11-5820685.html" TITLE="Click to recommend" class="last"></a></li>
	166
	167	<li class="vote"><div id="votecount" class="votecount" TITLE="How many people recommended this item">1 </div></li>
	168
	169	<script language="JavaScript">
	170	var http = createRequestObject();
	171	var existing_votes = '';
	172
	173	function createRequestObject()
	174	{
	175	var ro;
	176	var browser = navigator.appName;
	177	if(browser == "Microsoft Internet Explorer"){
	178	ro = new ActiveXObject("Microsoft.XMLHTTP");
	179	}else{
	180	ro = new XMLHttpRequest();
	181	}
	182	return ro;
	183	}
	184
	185	function Set_Cookie(name, value, expires, path)
	186	{
	187	// set time, it's in milliseconds
	188	var today = new Date();
	189	today.setTime( today.getTime() );
	190
	191	expires = expires * 1000 * 60 * 60 * 24;
	192	var expires_date = new Date( today.getTime() + (expires) );
	193
	194	document.cookie = name + "=" + escape( value ) + ";expires=" + expires_date.toGMTString() + ";path=" + path;
	195
	196	}
	197
	198	function sendVote()
	199	{
	200	http.open('get', '');
	201	http.onreadystatechange = handleResponse;
	202	http.send(null);
	203	}
	204
	205	function handleResponse()
	206	{
	207	if(http.readyState == 4)
	208	{
	209	var response = http.responseText;
	210	var temp_array = new Array();
	211	temp_array = response.split('~');
	212	var ranking = temp_array[0];
	213
	214	if (ranking > 0) {
	215	ranking = ranking;
	216	}
	217
	218	// Replace with ajax magic
	219	document.getElementById('votecount').innerHTML = ranking;
	220
	221	// Remove the thumbs
	222	var voter = document.getElementById('recommend');
	223	voter.className = "thanks";
	224	voter.innerHTML = "";
	225
	226	Set_Cookie('service',(existing_votes + '~85140'),30,'/');
	227	}
	228	}
	229	</script>
	230
	231
	232	</ul><!-- /toolbar -->
	233	</div><!-- /interact -->
	234	</div><!-- /contentHeader -->
	235
	236	<div id="articleText">
	237	<p class="takeaway"><b>Takeaway:</b> Learn two ways two declare an array in bash in this Linux tip.</p>
	238
	239	<div class="related">
	240	<div class="relatedBg">
	241	<!--Medusa Related Content-->
	242	<script type="text/javascript" src="http://service.techrepublic.com.com/wi?spot=related-js&format=text&count=5&null=true&id=TR.TA.1.5820685&referer=http%3A%2F%2Fwww.google.com%2Fsearch%3Fhl%3Dcs%26client%3Diceweasel-a%26rls%3Dorg.debian%253Acs-CZ%253Aunofficial%26q%3Dbash%2Barray%26btnG%3DHledat%26lr%3D"></script>
	243	<script type="text/javascript">getrelatedContent()</script>
	244	<!--/Medusa Related Content-->
	245	</div><!--relatedBg-->
	246	</div><!-- /related -->
	247
	248	<p>Assigning variables in bash is easily done and extremely\r
	249	useful, but like other programming languages, bash can also use arrays. This is\r
	250	particularly handy when you want to read the contents of a file into an array or\r
	251	simply keep your scripts more organized and logical.</p>\r
	252	\r
	253	<p>There are two ways of declaring an array:</p>\r
	254	\r
	255	<pre><code><br>declare -a FOO<br></code></pre>\r
	256	\r
	257	<p>This creates an empty array called FOO. You can also declare\r
	258	an array by assigning values to it:</p>\r
	259	\r
	260	<pre><code><br>FOO[2] = 'bar'<br></codE></pre>\r
	261	\r
	262	<p>This assigns the third element of the array to the value\r
	263	'bar'. In this instance, FOO[0] and FOO[1] are also\r
	264	created, but their values are empty.</p>\r
	265	\r
	266	<p>To populate an array, use:</p>\r
	267	\r
	268	<pre><code><br>FOO=( bar string 'some text' )<br></code></pre>\r
	269	\r
	270	<p>This assigns the first element (FOO[0])\r
	271	to 'bar', the second (FOO[1]) to 'string' and the final element (FOO[3]) to\r
	272	'some text'. Notice that the array elements are separated by a blank space, so\r
	273	if a value contains white spaces it must be quoted.</p>\r
	274	\r
	275	<p>To use an array, it is referred to as $FOO[2]\r
	276	but it also needs to be surrounded in curly braces, otherwise bash will not\r
	277	expand it correctly:</p>\r
	278	\r
	279	<pre><code><br>$ echo {$FOO[2]}<br>some text<br></code></pre>\r
	280	\r
	281	<p>To loop through an array, you can use a piece of shell code\r
	282	like the following:</p>\r
	283	\r
	284	<pre><code><br>\r
	285	#!/bin/sh</pre><pre>FOO=( bar string 'some text')<br>foonum=${#FOO}<br>\r
	286