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<div class="syntax">
<h2>syntax of While Loops</h2>
<P>#!/bin/sh <br>
while [ comand ] <br>
do <br>
statement to be exeuted if command is true <br>
done <br>
</P>
<h2>Exemple</h2>
#!/bin/sh <br>
INPUT_STRING=hello <br>
while [ "$INPUT_STRING"!="bye" ] <br>
do <br>
echo "please type something in (bye to quit) <br>
read INPUT_STRING <br>
echo "You typed: $INPUT_STRING" <br>
done <br>
<h3>Explanation</h3>
<P>In this exemple "echo" and read statement run will go forward until we type "bye" <br>
Normaly "while" command execute a code if this expression code is true, and stop only when is false or when say (type) stop.</P>
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<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>
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