<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<link rel="stylesheet" type="text/css" href="mystyle.css">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="keywords" content="if, unix, shell">
<meta name="author" content="Aleksandar Todorovic">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>if|if</title>
</head>
<body>
<header>
<div class="nav">
<ul>
<li><a href="index.html">home</a></li>
<li><a href="index_if.html">if</a>
<ul>
<li class="current"><a href="if.html"></a>if-fi</li>
<li><a href="if-else.html"></a>if-else</li>
<li><a href="elif.html"></a>if-elif</li>
</ul>
</li>
<li><a href="loops_index.html">Loops</a>
<ul>
<li><a href="while.html"></a>while</li>
<li><a href="for.html"></a>for</li>
</ul>
</li>
</ul>
</div>
</header>
<div class="syntax">
<h2>syntax of if</h2>
<P>if [ expresion ] <br>
then <br>
statement to be executed if expresion is true <br>
fi <br>
</P>
<div class="notice">
<h3>Important notice</h3>
<ul>
<li>if expression is a shell comand, then it will be <br>
assumed true if it return 0 after execution</li>
<li>If it is a boolean expression, then it would be true <br>
if it returns true</li>
<li>Space between braces and expression it's important because <br>
no space produce a syntax error</li>
<li>"fi"is "if backward</li>
</ul>
</div>
<h2>Exemple</h2>
<P>#!/bin/sh <br>
var1=20 <br>
var2=10
if[ var1==1var2 ] <br>
then <br>
echo "var1 is equal var2" <br>
fi
</div>
<footer>
<h4>Source</h4>
<ul>
<li>https://www.shellscript.sh/loops.html</li>
<li>https://www.autistici.org/loa/shodan/corsounix.pdf</li>
<li>https://www.guru4technoworld.wix.com</li>
</ul>
</footer>
</body>
</html>