62f06e5131
git-svn-id: svn+ssh://atelier.inf.usi.ch/home/bevilj/group-1@97 a672b425-5310-4d7a-af5c-997e18724b81
61 lines
1.1 KiB
HTML
61 lines
1.1 KiB
HTML
---
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layout: page
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category-page: scripts
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category-title: Scripting
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tags: redirect output input
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author: Dario Rasic
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title: Redirection
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---
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<br>
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<!-- Output redirection text -->
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<h2>Output as input</h2>
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<p>To redirect a certain output of the command-line we have to use the symbol ">".<br>
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In this case, we will use a file named "<i>hello.txt</i>", in which we want to insert
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a certain output ("Sun" in this case):<br>
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<pre>
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echo "Sun" > hello.txt
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</pre>
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So if we print the content of the file in our command-line, the output will be the following:
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<pre>
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cat hello.txt
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Sun
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</pre>
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If we want to append a certain output to an existing file,
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we just have to use ">>" symbols:</p>
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<pre>
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cat hello.txt
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Sun
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echo "Moon" >> hello.txt
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cat hello.txt
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Sun
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Moon
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</pre>
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<!-- Input redirection text -->
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<h2>Input as output</h2>
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To redirect an input from a file for a command, the symbol "<" is used.
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<pre>
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echo < $(cat hello.txt)
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Sun
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Moon
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</pre>
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This is particularly useful when chaining commands.
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<br>
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<!-- Chaining command text -->
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<h2>Chaining</h2>
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<br>
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<h1>To be completed</h1>
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</p>
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