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